Amazing Science
654.9K views | +40 today
Amazing Science
Amazing science facts - 3D_printing • aging • AI • anthropology • art • astronomy • bigdata • bioinformatics • biology • biotech • chemistry • computers • cosmology • education • environment • evolution • future • genetics • genomics • geosciences • green_energy • history • language • map • material_science • math • med • medicine • microscopy • nanotech • neuroscience • paleontology • photography • photonics • physics • postings • robotics • science • technology • video
Your new post is loading...
Scooped by Dr. Stefan Gruenwald
Scoop.it!

The impossible triple star KIC 2856960

The impossible triple star KIC 2856960 | Amazing Science | Scoop.it

There's news of an 'impossible' triple star system recently discovered by astronomers. One that 'defies known physics.' Needless to say, there's no need to abandon physics quite yet.


It all comes from a new paper being published in MNRAS titled "KIC 2856960: the impossible triple star." Despite the overly-hyped title, it is interesting work. It's based upon data gathered from the Kepler satellite, which looked at the brightness of stars over time looking for exoplanets. Kepler finds exoplanets via the transit method, where the brightness of a star can be seen to dip when a planet passes in front of it. But the method can also be used to study multiple star systems if they happen to have the right alignment. Just as a planet can cause a star to dip in brightness when it passes in front, one star passing in front of another can have a similar effect.


The team looked at the data from KIC 2856960, for which Kepler gathered data over 4 years. In the data we see a small dip in brightness about 4 times a day, and a larger dip every 204 days. From this, it looks like a close binary of smaller stars (with orbital periods of 0.26 days) orbiting a third star with a period of 204 days. So it is a fairly common triple star system. Not a big deal, move on to other data.


But this team wanted to determine some of the characteristics of this system, such as their exact orbits and masses, so they looked at the data in more detail. Determining the details of a system can be tricky. There are all sorts of things that can add to noise in your data, such as starspots and other stellar activity. This is why exoplanets are divided into confirmed planets and candidate planets. Once you've eliminated the noise you can, you try to match the observed fluctuations to particular orbits, and then see if those orbits are stable. Sometimes the results can be deceiving.


What the team found was that the more they looked at the data for KIC 2856960, the more confusing things got. At first glance it looks like a triple star system, but when they tested candidate orbits, none of them seemed to fit. Several of them kind of fit, but there was always some unexplained fluctuation in the data. So the team tried other models, and found a 4-star system that basically worked, but it required the orbits one binary system to be in exact resonance with the other, which seems highly unlikely.


In other words, the Kepler data is inconclusive. It could be a strange 4-star system, or it could be a triple-star system with something else buried in the data. We can't be certain at this point. This does not make KIC 2856960 an "impossible" system. There's no evidence that it is defying known physics, just that the data is odd and we don't understand it.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Two new Jupiter-sized extrasolar planets found, each orbiting one star of a binary-star system

Two new Jupiter-sized extrasolar planets found, each orbiting one star of a binary-star system | Amazing Science | Scoop.it

Astronomers at Keele University have found two new Jupiter-sized extra-solar planets, each orbiting one star of a binary-star system.


Most known extra-solar planets orbit stars that are alone, like our Sun. Yet many stars are part of binary systems, twin stars formed from the same gas cloud.  Now, for the first time, two stars of a binary system are both found to host a ``hot Jupiter'' exoplanet.


The discoveries, around the stars WASP-94A and WASP-94B, were made by a team of British, Swiss and Belgian astronomers. The Keele-led WASP-South survey found tiny dips in the light of WASP-94A, suggesting that a Jupiter-like planet was transiting the star; Swiss astronomers then showed the existence of planets around both WASP-94A and then its twin WASP-94B. Marion Neveu-VanMalle (Geneva Observatory), who wrote the announcement paper, explains: "We observed the other star by accident, and then found a planet around that one also!"


Hot Jupiter planets are much closer to their stars than our own Jupiter, with a "year" lasting only a few days. They are rare, so it would be unlikely to find two Hot Jupiters in the same star system by chance.   Perhaps WASP-94 has just the right conditions for producing Hot Jupiters?  If so WASP-94 could be an important system for understanding why Hot Jupiters are so close to the star they orbit.


The existence of huge, Jupiter-size planets so near to their stars is a long-standing puzzle, since they cannot form near to the star where it is far too hot.


They must form much further out, where it is cool enough for ices to freeze out of the proto-planetary disk circling the young star, hence forming the core of a new planet.   Something must then move the planet into a close orbit, and one likely mechanism is an interaction with another planet or star.  Finding Hot-Jupiter planets in two stars of a binary pair might allow us to study the processes that move the planets inward.


Professor Coel Hellier, of Keele University, remarks: "WASP-94 could turn into one of the most important discoveries from WASP-South. The two stars are relatively bright, making it easy to study their planets, so WASP-94 could be used to discover the compositions of the atmospheres of exoplanets".


The WASP survey is the world's most successful search for hot-Jupiter planets that pass in front of (transit) their star. The WASP-South survey instrument scans the sky every clear night, searching hundreds of thousands of stars for transits. The Belgian team selects the best WASP candidates by obtaining high-quality data of transit light curves.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Iso-propyl cyanide has been detected in a star-forming cloud 27,000 light-years from Earth

Iso-propyl cyanide has been detected in a star-forming cloud 27,000 light-years from Earth | Amazing Science | Scoop.it

Scientists have found the beginnings of life-bearing chemistry at the centre of the galaxy. Iso-propyl cyanide has been detected in a star-forming cloud 27,000 light-years from Earth. Its branched carbon structure is closer to the complex organic molecules of life than any previous finding from interstellar space.


The discovery suggests the building blocks of life may be widespread throughout our galaxy. Various organic molecules have previously been discovered in interstellar space, but i-propyl cyanide is the first with a branched carbon backbone.


The branched structure is important as it shows that interstellar space could be the origin of more complex branched molecules, such as amino acids, that are necessary for life on Earth. Dr Arnaud Belloche from the Max Planck Institute for Radio Astronomy is lead author of the research, which appears in the journal Science.


"Amino acids on Earth are the building blocks of proteins, and proteins are very important for life as we know it. The question in the background is: is there life somewhere else in the galaxy?"

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

HAT-P-11b exo-Neptune with clear skies: Smallest exoplanet ever found to have steamy water vapour

HAT-P-11b exo-Neptune with clear skies: Smallest exoplanet ever found to have steamy water vapour | Amazing Science | Scoop.it
Astronomers using data from the NASA/ESA Hubble Space Telescope, the Spitzer Space Telescope, and the Kepler Space Telescope have discovered clear skies and steamy water vapour on a planet outside our Solar System. The planet, known as HAT-P-11b, is about the size of Neptune, making it the smallest exoplanet ever on which water vapour has been detected. The results will appear in the online version of the journal Nature on 24 September 2014.


The discovery is a milestone on the road to eventually finding molecules in the atmospheres of smaller, rocky planets more akin to Earth. Clouds in the atmospheres of planets can block the view of what lies beneath them. The molecular makeup of these lower regions can reveal important information about the composition and history of a planet. Finding clear skies on a Neptune-size planet is a good sign that some smaller planets might also have similarly good visibility.


"When astronomers go observing at night with telescopes, they say 'clear skies' to mean good luck," said Jonathan Fraine of the University of Maryland, USA, lead author of the study. "In this case, we found clear skies on a distant planet. That's lucky for us because it means clouds didn't block our view of water molecules."


HAT-P-11b is a so-called exo-Neptune — a Neptune-sized planet that orbits another star. It is located 120 light-years away in the constellation of Cygnus (The Swan). Unlike Neptune, this planet orbits closer to its star, making one lap roughly every five days. It is a warm world thought to have a rocky core, a mantle of fluid and ice, and a thick gaseous atmosphere. Not much else was known about the composition of the planet, or other exo-Neptunes like it, until now.

"We set out to look at the atmosphere of HAT-P-11b without knowing if its weather would be cloudy or not," said Nikku Madhusudhan, from the University of Cambridge, UK, part of the study team. "By using transmission spectroscopy, we could use Hubble to detect water vapour in the planet. This told us that the planet didn't have thick clouds blocking the view and is a very hopeful sign that we can find and analyze more cloudless, smaller, planets in the future. It is groundbreaking!"


Before the team could celebrate they had to be sure that the water vapour was from the planet and not from cool starspots — "freckles" on the face of stars — on the parent star. Luckily, Kepler had been observing the patch of sky in which HAT-P-11b happens to lie for years. Those visible-light data were combined with targeted infrared Spitzer observations. By comparing the datasets the astronomers could confirm that the starspots were too hot to contain any water vapour, and so the vapour detected must belong to the planet.


The results from all three telescopes demonstrate that HAT-P-11b is blanketed in water vapour, hydrogen gas, and other yet-to-be-identified molecules. So in fact it is not only the smallest planet to have water vapour found in its atmosphere but is also the smallest planet for which molecules of any kind have been directly detected using spectroscopy [1]. Theorists will be drawing up new models to explain the planet's makeup and origins.

more...
No comment yet.
Rescooped by Dr. Stefan Gruenwald from Physics
Scoop.it!

Photonic Positive: It’s a go for LUX-Zeplin experiment in dark matter

Photonic Positive: It’s a go for LUX-Zeplin experiment in dark matter | Amazing Science | Scoop.it
The U.S. Department of Energy’s Office of Science and the National Science Foundation recently gave the go-ahead to LUX-Zeplin (LZ), a key experiment in the hunt for dark matter, the invisible substance that may make up a large part of the universe.

“We emerged from a very intense competition,” said McKinsey, whose ongoing LUX (Large Underground Xenon) experiment looks for dark matter with a liquid xenon detector placed 4,850 feet below the Earth’s surface. The device resides at the Sanford Underground Research Facility, in South Dakota’s Black Hills. The new, LZ device will boost the size and effectiveness of the original LUX technology.

“We have the most sensitive detector in the world, with LUX,” McKinsey said. “LZ will be hundreds of times more sensitive. It’s gratifying to see that our approach is being validated.” LZ is an international effort, involving scientists from 29 institutions in the United States, Portugal, Russia, and the United Kingdom. The DOE’s Lawrence Berkeley National Lab manages the experiment.

Dark matter is a scientific placeholder, of sorts. Although it can’t be seen or felt, its existence is thought to explain a number of important behaviors of the universe, including the structural integrity of galaxies.

LZ’s approach posits that dark matter may be composed of Weakly Interacting Massive Particles – known as WIMPs – which pass through ordinary matter virtually undetected. The experiment aims to spot these particles as they move through a container of dense, liquid xenon. That container will be surrounded by a tank of water, along with an array of sophisticated light sensors and other systems.

Via José Gonçalves
more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

NASA prediction: We will find alien life within the next 20 years

NASA prediction: We will find alien life within the next 20 years | Amazing Science | Scoop.it

Many scientists believe we are not alone in the universe. It's probable, they say, that life could have arisen on at least some of the billions of planets thought to exist in our galaxy alone -- just as it did here on planet Earth. This basic question about our place in the Universe is one that may be answered by scientific investigations. What are the next steps to finding life elsewhere?


Experts from NASA and its partner institutions addressed this question on July 14, 2014 at a public talk held at NASA Headquarters in Washington. They outlined NASA's roadmap to the search for life in the universe, an ongoing journey that involves a number of current and future telescopes.


"Sometime in the near future, people will be able to point to a star and say, 'that star has a planet like Earth'," says Sara Seager, professor of planetary science and physics at the Massachusetts Institute of Technology in Cambridge, Massachusetts. "Astronomers think it is very likely that every single star in our Milky Way galaxy has at least one planet."


NASA's quest to study planetary systems around other stars started with ground-based observatories, then moved to space-based assets like the Hubble Space Telescope, the Spitzer Space Telescope, and the Kepler Space Telescope. Today's telescopes can look at many stars and tell if they have one or more orbiting planets. Even more, they can determine if the planets are the right distance away from the star to have liquid water, the key ingredient to life as we know it.


The NASA roadmap will continue with the launch of the Transiting Exoplanet Surveying Satellite (TESS) in 2017, the James Webb Space Telescope (Webb Telescope) in 2018, and perhaps the proposed Wide Field Infrared Survey Telescope - Astrophysics Focused Telescope Assets (WFIRST-AFTA) early in the next decade. These upcoming telescopes will find and characterize a host of new exoplanets -- those planets that orbit other stars -- expanding our knowledge of their atmospheres and diversity. The Webb telescope and WFIRST-AFTA will lay the groundwork, and future missions will extend the search for oceans in the form of atmospheric water vapor and for life as in carbon dioxide and other atmospheric chemicals, on nearby planets that are similar to Earth in size and mass, a key step in the search for life.


"This technology we are using to explore exoplanets is real," said John Grunsfeld, astronaut and associate administrator for NASA's Science Mission Directorate in Washington. "The James Webb Space Telescope and the next advances are happening now. These are not dreams -- this is what we do at NASA."


Since its launch in 2009, Kepler has dramatically changed what we know about exoplanets, finding most of the more than 5,000 potential exoplanets, of which more than 1700 have been confirmed. The Kepler observations have led to estimates of billions of planets in our galaxy, and shown that most planets within one astronomical unit are less than three times the diameter of Earth. Kepler also found the first Earth-size planet to orbit in the "habitable zone" of a star, the region where liquid water can pool on the surface.


"What we didn't know five years ago is that perhaps 10 to 20 percent of stars around us have Earth-size planets in the habitable zone," says Matt Mountain, director and Webb telescope scientist at the Space Telescope Science Institute in Baltimore. "It's within our grasp to pull off a discovery that will change the world forever. It is going to take a continuing partnership between NASA, science, technology, the U.S. and international space endeavors, as exemplified by the James Webb Space Telescope, to build the next bridge to humanity's future."


This decade has seen the discovery of more and more super Earths, which are rocky planets that are larger and heftier than Earth. Finding smaller planets, the Earth twins, is a tougher challenge because they produce fainter signals. Technology to detect and image these Earth-like planets is being developed now for use with the future space telescopes. The ability to detect alien life may still be years or more away, but the quest is underway.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Fermi Paradox: Where is the Great Filter and Where Are We?

Fermi Paradox: Where is the Great Filter and Where Are We? | Amazing Science | Scoop.it

As many stars as there are in our galaxy (100 - 400 billion), there are roughly an equal number of galaxies in the observable universe -- so for every star in the colossal Milky Way, there's a whole galaxy out there. All together, that comes out to the typically quoted range of between 10**22 and 10**24 total stars, which means that for every grain of sand on Earth, there are 10,000 stars out there.


The science world isn't in total agreement about what percentage of those stars are "sun-like" (similar in size, temperature, and luminosity) -- opinions typically range from 5 percent to 20 percent. Going with the most conservative side of that (5 percent), and the lower end for the number of total stars (10**22), gives us 500 quintillion, or 500 billion billion sun-like stars.


There's also a debate over what percentage of those sun-like stars might be orbited by an Earth-like planet (one with similar temperature conditions that could have liquid water and potentially support life similar to that on Earth). Some say it's as high as 50 percent, but let's go with the more conservative 22 percent that came out of a recent PNAS study. That suggests that there's a potentially-habitable Earth-like planet orbiting at least 1 percent of the total stars in the universe -- a total of 100 billion billion Earth-like planets.


So there are 100 Earth-like planets for every grain of sand in the world. Think about that next time you're on the beach. Moving forward, we have no choice but to get completely speculative. Let's imagine that after billions of years in existence, 1 percent of Earth-like planets develop life (if that's true, every grain of sand would represent one planet with life on it). And imagine that on 1 percent of those planets, the life advances to an intelligent level like it did here on Earth. That would mean there were 10 quadrillion, or 10 million billion intelligent civilizations in the observable universe.


Moving back to just our galaxy, and doing the same math on the lowest estimate for stars in the Milky Way (100 billion), we'd estimate that there are 1 billion Earth-like planets and 100,000 intelligent civilizations in our galaxy.


So where is everybody?

Welcome to the Fermi Paradox. There is something called "The Great Filter". The Great Filter theory says that at some point from pre-life to Type III intelligence, there's a wall that all or nearly all attempts at life hit. There's some stage in that long evolutionary process that is extremely unlikely or impossible for life to get beyond. That stage is The Great Filter.  If this theory is true, the big question is, Where in the timeline does the Great Filter occur? This article gives different possibilities and scenarios.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

NASA unveils world's largest spacecraft welding tool for space launch system

NASA unveils world's largest spacecraft welding tool for space launch system | Amazing Science | Scoop.it

The largest spacecraft welding tool in the world, the Vertical Assembly Center officially is open for business at NASA's Michoud Assembly Facility in New Orleans. The 170-foot-tall, 78-foot-wide giant completes a world-class welding toolkit that will be used to build the core stage of America's next great rocket, the Space Launch System (SLS).

SLS will be the most powerful rocket ever built for deep space missions, including to an asteroid and eventually Mars. The core stage, towering more than 200 feet tall (61 meters) with a diameter of 27.6 feet (8.4 meters), will store cryogenic liquid hydrogen and liquid oxygen that will feed the rocket's four RS-25 engines.


"This rocket is a game changer in terms of deep space exploration and will launch NASA astronauts to investigate asteroids and explore the surface of Mars while opening new possibilities for science missions, as well," said NASA Administrator Charles Bolden during a ribbon-cutting ceremony at Michoud Friday.


The Vertical Assembly Center is part of a family of state-of-the-art tools designed to weld the core stage of SLS. It will join domes, rings and barrels to complete the tanks or dry structure assemblies. It also will be used to perform evaluations on the completed welds. Boeing is the prime contractor for the SLS core stage, including avionics.


"The SLS Program continues to make significant progress," said Todd May, SLS program manager. "The core stage and boosters have both completed critical design review, and NASA recently approved the SLS Program's progression from formulation to development. This is a major milestone for the program and proof the first new design for SLS is mature enough for production."

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Starting march 2015, the general public will be able to vote names for already discovered exoplanets

Starting march 2015, the general public will be able to vote names for already discovered exoplanets | Amazing Science | Scoop.it

What will be named?

  1. Exoplanets belonging to a list of 305 well-characterised exoplanets, discovered prior to 31 December 2008, and their host stars. The date refers to the date of submission to a refereed journal. Many exoplanets discovered after this date require confirmation or are incompletely characterised.
  2. These exoplanets belong to 260 exoplanetary systems comprising one to five members.
  3. These systems have been selected for naming by the IAU Working Group Exoplanets for the Public, and are published on the www.NameExoWorlds.org website.
  4. This master list will be referred to as the ExoWorlds list and forms the basis of the NameExoWorlds campaign led by the IAU’s Public Naming of Planets and Planetary Satellites Working Group.
  5. The exoplanetary systems in the ExoWorlds list can be named and recognised by the IAU only via the NameExoWorlds campaign.
  6. A vote will be organised among registered organisations (see next Section) to select the top 20-30 most popular exoplanetary systems in the ExoWorlds list for naming.
  7. During the first NameExoWorlds campaign, proposals for names for members of the selected 20-30 ExoWorlds (host stars and their exoplanets) shall be submitted towww.NameExoWorlds.org only by the registered organisations.


Who can submit names?

  1. Only public astronomical organisations (such as Planetariums, Science Centres, Amateur Astronomy Clubs, Online Astronomy platforms) or non-profit astronomy-interested organisations (such as High schools, Cultural clubs) with a proven interest in astronomy, (hereafter "organisations" for short) based in any country, shall be allowed to propose names.
  2. To suggest names, these organisations must first register on the IAU Directory for World Astronomy website providing their website URL, the organisation’s registration number/certificate/document number testifying its status, and the full name, e-mail and postal address of a contact person.
  3. The website of the organisation shall demonstrate its activity or interest in astronomy, and a verifiable non-profit status.


How can names be submitted?

  1. Registered organisations may send only one proposal, concerning only one of the 20-30 ExoWorlds selected, independently of the number of exoplanets belonging to the system of their choice.
  2. These organisations may not gather suggestions for names by means of sales, donations or other financial transactions. Organisations may not sell their right to suggest names to other entities or try to gain any other non-commercial or commercial benefit from their right to suggest names to the IAU.
  3. Organisations shall send their naming proposals to www.NameExoWorlds.org along with a detailed justification of the host star and exoplanet names (of a single ExoWorld) in English (max. 250 words).
more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Interactive dark matter could explain Milky Way’s missing satellite galaxies

Interactive dark matter could explain Milky Way’s missing satellite galaxies | Amazing Science | Scoop.it

Scientists believe they have found a way to explain why there are not as many galaxies orbiting the Milky Way as expected. Computer simulations of the formation of our galaxy suggest that there should be many more small galaxies around the Milky Way than are observed through telescopes. This has thrown doubt on the generally accepted theory of cold dark matter, an invisible and mysterious substance that scientists predict should allow for more galaxy formation around the Milky Way than is seen.


Now cosmologists and particle physicists at theInstitute for Computational Cosmology and the Institute for Particle Physics Phenomenology, at Durham University, working with colleagues at LAPTh College & University in France, think they have found a potential solution to the problem.


Writing in the journal Monthly Notices of the Royal Astronomical Society, the scientists suggest that dark matter particles, as well as feeling the force of gravity, could have interacted with photons and neutrinos in the young Universe, causing the dark matter to scatter.


Scientists think clumps of dark matter – or haloes – that emerged from the early Universe, trapped the intergalactic gas needed to form stars and galaxies. Scattering the dark matter particles wipes out the structures that can trap gas, stopping more galaxies from forming around the Milky Way and reducing the number that should exist.


Lead author Dr Celine Boehm, in the Institute for Particle Physics Phenomenology at Durham University, said: "We don’t know how strong these interactions should be, so this is where our simulations come in."


"By tuning the strength of the scattering of particles, we change the number of small galaxies, which lets us learn more about the physics of dark matter and how it might interact with other particles in the Universe."


"This is an example of how a cosmological measurement, in this case the number of galaxies orbiting the Milky Way, is affected by the microscopic scales of particle physics."


There are several theories about why there are not more galaxies orbiting the Milky Way, which include the idea that heat from the Universe’s first stars sterilised the gas needed to form stars. The researchers say their current findings offer an alternative theory and could provide a novel technique to probe interactions between other particles and cold dark matter.


Co-author Professor Carlton Baugh said: "Astronomers have long since reached the conclusion that most of the matter in the Universe consists of elementary particles known as dark matter." "This model can explain how most of the Universe looks, except in our own backyard where it fails miserably."


"The model predicts that there should be many more small satellite galaxies around our Milky Way than we can observe." "However, by using computer simulations to allow the dark matter to become a little more interactive with the rest of the material in the Universe, such as photons, we can give our cosmic neighbourhood a makeover and we see a remarkable reduction in the number of galaxies around us compared with what we originally thought."


The calculations were carried out using the COSMA supercomputer at Durham University, which is part of the UK-wide DiRAC super-computing framework.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

How NASA's new Orbiting Carbon Observatory will help us understand alien worlds

How NASA's new Orbiting Carbon Observatory will help us understand alien worlds | Amazing Science | Scoop.it

NASA successfully launched the Orbiting Carbon Observatory-2 (OCO-2), a remote sensing satellite on a mission to precisely measure carbon dioxide levels in our planet's atmosphere. As a bonus OCO-2 will also help prepare us for eventually probing the atmospheres of alien worlds in sharper detail.

Why study carbon dioxide? This gas essentially serves as Earth's thermostat. As a "greenhouse gas," carbon dioxide absorbs radiation emitted by the planet's surface that would otherwise escape into space. The more carbon dioxide in the atmosphere, the warmer Earth gets.


Over geological history, carbon dioxide levels have waxed and waned, driving hotter and cooler climatic epochs. Occasionally, the scales have tipped too far in either direction, pushing life on Earth to the brink. The "snowball Earth" period of 650 million years ago and the hot-tub tropical waters of the early Triassic period are just two examples.


Usually, life and the planet itself work together to moderate the carbon dioxide swings and their attendant climatic extremes. Carbon dioxide naturally ends up in the atmosphere when it's released by forest fires, volcanoes, decaying organic matter, and other sources. Plants, rocks and the oceans—dubbed "sinks"—absorb a comparable amount of this released gas, maintaining a carbon balance.


OCO-2′s mission is to learn more about the Earth's cycle of inhaling and exhaling carbon dioxide. "We're basically watching the Earth breathe," said David Crisp, OCO-2′s science team leader at NASA's Jet Propulsion Laboratory in Pasadena, Ca.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Water clouds tentatively detected on a brown dwarf just 7 light-years from Earth

Water clouds tentatively detected on a brown dwarf just 7 light-years from Earth | Amazing Science | Scoop.it

They're the first water clouds ever seen beyond our solar system.


Astronomers have found signs of water ice clouds on an object just 7.3 light-years from Earth—less than twice the distance of Alpha Centauri, the nearest star system to the sun. If confirmed, the discovery is the first sighting of water clouds beyond our solar system. The clouds shroud a Jupiter-sized object known as a brown dwarf and should yield insight into the nature of cool giant planets orbiting other suns.


Kevin Luhman, an astronomer at Pennsylvania State University, University Park, recently discovered the nearby object by using images from NASA’s WISE infrared space telescope, which scanned the sky from 2010 to 2011. A brown dwarf is a failed star and has so little mass that it can't sustain nuclear reactions, so after its birth it fades and cools. This brown dwarf, named WISE J0855-0714, is the coldest known. Its temperature is slightly below the freezing point of water, so it's colder than Earth's mean temperature but warmer than Jupiter’s.


"I've been obsessed with this object since its discovery," says astronomer Jacqueline Faherty of the Carnegie Institution for Science in Washington, D.C. The new neighbor resembles a giant planet—it's as large as Jupiter and three to 10 times as massive—but is solitary, which means it has no sun whose glare interferes with our view of it. Moreover, it's nearby: the fourth closest system to the sun, after Alpha Centauri, Barnard's star, and Luhman 16.


Still, because the object is small and cold, it's so dim that no ground-based observatory had seen it. "I went to battle at the telescope to try and get this detection," Faherty says. "I wanted to put war paint under my eyes and wear a bandanna, because I knew this was not going to be an easy thing to do. At the telescope, I've never been so nervous. I've never wanted clear conditions so badly."


For 3 nights in May, Faherty used the 6.5-meter Magellan Baade telescope in Chile to acquire 151 near-infrared images that she later combined to yield a detection. "I'm absolutely elated," she says. Moreover, as her team will report in The Astrophysical Journal Letters, the observed colors match models of a brown dwarf with clouds of water ice and clouds of sodium sulfide.


"It's incredibly interesting," says Jonathan Fortney of the University of California, Santa Cruz, an astronomer who helped develop those models but was not involved in the discovery. "It's tentative," he says, but "it's the first evidence for water clouds" outside our solar system. Even within the solar system, observers can see water clouds on only Earth and Mars; the giant planets are so cold that ammonia ice clouds cover the water clouds on Jupiter and Saturn while the atmospheres of Uranus and Neptune block the view there.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

NASA: 101 Counted Geysers on Icy Saturn Moon Enceladus

NASA: 101 Counted Geysers on Icy Saturn Moon Enceladus | Amazing Science | Scoop.it
Scientists using mission data from NASA’s Cassini spacecraft have identified 101 distinct geysers erupting on Saturn’s icy moon Enceladus. Their analysis suggests it is possible for liquid water to reach from the moon’s underground sea all the way to its surface.


Over a period of almost seven years, Cassini’s cameras surveyed the south polar terrain of the small moon, a unique geological basin renowned for its four prominent "tiger stripe” fractures and the geysers of tiny icy particles and water vapor first sighted there nearly 10 years ago. The result of the survey is a map of 101 geysers, each erupting from one of the tiger stripe fractures, and the discovery that individual geysers are coincident with small hot spots. These relationships pointed the way to the geysers’ origin.


After the first sighting of the geysers in 2005, scientists suspected repeated flexing of Enceladus by Saturn’s tides as the moon orbits the planet had something to do with their behavior. One suggestion included the back-and-forth rubbing of opposing walls of the fractures generating frictional heat that turned ice into geyser-forming vapor and liquid.


Alternate views held that the opening and closing of the fractures allowed water vapor from below to reach the surface. Before this new study, it was not clear which process was the dominating influence. Nor was it certain whether excess heat emitted by Enceladus was everywhere correlated with geyser activity.


To determine the surface locations of the geysers, researchers employed the same process of triangulation used historically to survey geological features on Earth, such as mountains. When the researchers compared the geysers’ locations with low-resolution maps of thermal emission, it became apparent the greatest geyser activity coincided with the greatest thermal radiation. Comparisons between the geysers and tidal stresses revealed similar connections. However, these correlations alone were insufficient to answer the question, “What produces what?”


The answer to this mystery came from comparison of the survey results with high-resolution data collected in 2010 by Cassini’s heat-sensing instruments. Individual geysers were found to coincide with small-scale hot spots, only a few dozen feet (or tens of meters) across, which were too small to be produced by frictional heating, but the right size to be the result of condensation of vapor on the near-surface walls of the fractures. This immediately implicated the hot spots as the signature of the geysering process.


“Once we had these results in hand we knew right away heat was not causing the geysers, but vice versa,” said Carolyn Porco, leader of the Cassini imaging team from the Space Science Institute in Boulder, Colorado, and lead author of the first paper. “It also told us the geysers are not a near-surface phenomenon, but have much deeper roots.”


more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Ancient magma plumbing found buried below moon's largest dark spot

Ancient magma plumbing found buried below moon's largest dark spot | Amazing Science | Scoop.it

Scientists have found a nearly square peg underneath a round hole—on the moon. Several kilometers below Oceanus Procellarum, the largest dark spot on the moon’s near side, scientists have discovered a giant rectangle thought to be the remnants of a geological plumbing system that spilled lava across the moon about 3.5 billion years ago. The features are similar to rift valleys on Earth—regions where the crust is cooling, contracting, and ripping apart. Their existence shows that the moon, early in its history, experienced tectonic and volcanic activity normally associated with much bigger planets.


“We’re realizing that the early moon was a much more dynamic place than we thought,” says Jeffrey Andrews-Hanna, a planetary scientist at the Colorado School of Mines in Golden and lead author of a new study of the Procellarum’s geology. The discovery also casts doubt on the decades-old theory that the circular Procellarum region is a basin, or giant crater, created when a large asteroid slammed into the moon. “We don’t expect a basin rim to have corners,” Andrews-Hanna says.


The work is based on data gathered by GRAIL (Gravity Recovery and Interior Laboratory), a pair of NASA spacecraft that orbited the moon in 2012. Sensitive to tiny variations in the gravitational tug of the moon, GRAIL mapped density variations below the surface (because regions of higher density produce slightly higher gravitational forces). Below known impact basins, GRAIL found the expected ringlike patterns, but underneath the Procellarum region, the mysterious rectangle emerged. “It was a striking pattern that demanded an explanation,” Andrews-Hanna says.


Scientists already know that the Procellarum region is rich in radioactive elements that billions of years ago would have produced excess heat. The study team theorizes that as this region cooled, the rock would have cracked in geometrical patterns, like honeycomb patterns seen on Earth in basalt formations, but on a much larger scale. In a study published today inNature, the researchers propose that these cracks eventually grew into rift valleys, where magma from the moon’s mantle welled up and pushed apart blocks of crust. Lava spilled out and paved over the Oceanus Procellarum, creating the dark spot that is seen today. The extra weight of this dense material would have caused the whole region to sink slightly and form the topographic low that has made the Procellarum seem like a basin.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Astrophysicist Joshua Frieman discusses attempts to characterize dark energy with the Dark Energy Detection Camera

Astrophysicist Joshua Frieman discusses attempts to characterize dark energy with the Dark Energy Detection Camera | Amazing Science | Scoop.it

Like most theoretical cosmologists, Joshua Frieman was thrilled when astronomers announced in 1998 that the expansion of the universe appeared to be speeding up, driven by an invisible agent that they called “dark energy.”


Frieman and his fellow theorists imagined two possible causes for the cosmic acceleration: Dark energy could be the quantum jitter of empty space, a “cosmological constant” that continues to accrue as space expands, pushing outward ever more forcefully. Alternately, a yet-undetected force field could pervade the cosmos, one akin to the field that scientists believe powered the exponential expansion of the universe during the Big Bang.


But the scientists also realized that the two options would have nearly identical observational consequences, and either theory could fit the crude measurements to date.


To distinguish between them, Frieman, a professor of astronomy and astrophysics at the University of Chicago and a senior staff scientist at the Fermi National Accelerator Laboratory (Fermilab) in nearby Batavia, Ill., co-founded the Dark Energy Survey (DES), a $50 million, 300-person experiment. The centerpiece of the project is the Dark Energy Camera, or DECam, a 570-megapixel, optical and near-infrared CCD detector built at Fermilab and installed on the four-meter Blanco Telescope in Chile two years ago. By observing 300 million galaxies spanning 10 billion light-years, DES aims to track the cosmic acceleration more precisely than ever before in hopes of favoring one hypothesis over the other. Frieman and his team are now reporting their first results.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Earth's water is older than the sun: Likely originated as ices that formed in interstellar space

Earth's water is older than the sun: Likely originated as ices that formed in interstellar space | Amazing Science | Scoop.it
Water was crucial to the rise of life on Earth and is also important to evaluating the possibility of life on other planets. Identifying the original source of Earth's water is key to understanding how life-fostering environments come into being and how likely they are to be found elsewhere. New work found that much of our solar system's water likely originated as ices that formed in interstellar space.

Water is found throughout our Solar System. Not just on Earth, but on icy comets and moons, and in the shadowed basins of Mercury. Water has been found included in mineral samples from meteorites, the Moon, and Mars.


Comets and asteroids in particular, being primitive objects, provide a natural "time capsule" of the conditions during the early days of our Solar System. Their ices can tell scientists about the ice that encircled the Sun after its birth, the origin of which was an unanswered question until now.


In its youth, the Sun was surrounded by a protoplanetary disk, the so-called solar nebula, from which the planets were born. But it was unclear to researchers whether the ice in this disk originated from the Sun's own parental interstellar molecular cloud, from which it was created, or whether this interstellar water had been destroyed and was re-formed by the chemical reactions taking place in the solar nebula.


"Why this is important? If water in the early Solar System was primarily inherited as ice from interstellar space, then it is likely that similar ices, along with the prebiotic organic matter that they contain, are abundant in most or all protoplanetary disks around forming stars," Alexander explained.


"But if the early Solar System's water was largely the result of local chemical processing during the Sun's birth, then it is possible that the abundance of water varies considerably in forming planetary systems, which would obviously have implications for the potential for the emergence of life elsewhere."

more...
Greenconflict Solutions's curator insight, September 26, 2014 12:59 PM

This is really interesting!!

Scooped by Dr. Stefan Gruenwald
Scoop.it!

Rethinking the origins of the universe: Can black holes really develop?

Rethinking the origins of the universe: Can black holes really develop? | Amazing Science | Scoop.it

By merging two seemingly conflicting theories, Laura Mersini-Houghton, a physics professor at UNC-Chapel Hill in the College of Arts and Sciences, has proven, mathematically, that black holes can never come into being in the first place. The work not only forces scientists to reimagine the fabric of space-time, but also rethink the origins of the universe. “I’m still not over the shock,” said Mersini-Houghton. “We’ve been studying this problem for a more than 50 years and this solution gives us a lot to think about.”


For decades, black holes were thought to form when a massive star collapses under its own gravity to a single point in space – imagine the Earth being squished into a ball the size of a peanut – called a singularity. So the story went, an invisible membrane known as the event horizon surrounds the singularity and crossing this horizon means that you could never cross back. It’s the point where a black hole’s gravitational pull is so strong that nothing can escape it.


The reason black holes are so bizarre is that it pits two fundamental theories of the universe against each other. Einstein’s theory of gravity predicts the formation of black holes but a fundamental law of quantum theory states that no information from the universe can ever disappear. Efforts to combine these two theories lead to mathematical nonsense, and became known as the information loss paradox.


In 1974, Stephen Hawking used quantum mechanics to show that black holes emit radiation. Since then, scientists have detected fingerprints in the cosmos that are consistent with this radiation, identifying an ever-increasing list of the universe’s black holes.


But now Mersini-Houghton describes an entirely new scenario. She and Hawking both agree that as a star collapses under its own gravity, it produces Hawking radiation. However, in her new work, Mersini-Houghton shows that by giving off this radiation, the star also sheds mass. So much so that as it shrinks it no longer has the density to become a black hole.


Before a black hole can form, the dying star swells one last time and then explodes. A singularity never forms and neither does an event horizon. The take home message of her work is clear: there is no such thing as a black hole.


The paper, which was recently submitted to ArXiv, an online repository of physics papers that is not peer-reviewed, offers exact numerical solutions to this problem and was done in collaboration with Harald Peiffer, an expert on numerical relativity at the University of Toronto. An earlier paper, by Mersini-Houghton, originally submitted to ArXiv in June, was published in the journal Physics Letters B, and offers approximate solutions to the problem.


Experimental evidence may one day provide physical proof as to whether or not black holes exist in the universe. But for now, Mersini-Houghton says the mathematics are conclusive.


Many physicists and astronomers believe that our universe originated from a singularity that began expanding with the Big Bang. However, if singularities do not exist, then physicists have to rethink their ideas of the Big Bang and whether it ever happened.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

‘Big Bang Signal’ Could All Be Just Dust

‘Big Bang Signal’ Could All Be Just Dust | Amazing Science | Scoop.it

There was little need, before, to know exactly how much dust peppers outer space, far from the plane of the Milky Way. Scientists understood that the dimly radiating grains aligned with our galaxy’s magnetic field and that the field’s twists and turns gave a subtle swirl to the dust glow. But those swirls were too faint to see. Only since March, when researchers claimed to have glimpsed the edge of space and time with a fantastically sensitive telescope, has the dust demanded a reckoning. For, like a cuckoo egg masquerading in a warbler’s nest, its pattern mimics a predicted signal from the Big Bang.


Now, scientists have shown that the swirl pattern touted as evidence of primordial gravitational waves — ripples in space and time dating to the universe’s explosive birth — could instead all come from magnetically aligned dust. A new analysis of data from the Planck space telescope has concluded that the tiny silicate and carbonate particles spewed into interstellar space by dying stars could account for as much as 100 percent of the signal detected by the BICEP2 telescope and announced to great fanfare this spring.


The Planck analysis is “relatively definitive in that we can’t exclude that the entirety of our signal is from dust,” said Brian Keating, an astrophysicist at the University of California, San Diego, and a member of the BICEP2 collaboration.


“We were, of course, disappointed,” said Planck team member Jonathan Aumont of the Université Paris-Sud.


The new dust analysis leaves open the possibility that part of the BICEP2 signal comes from primordial gravitational waves, which are the long-sought fingerprints of a leading Big Bang theory called “inflation.” If the universe began with this brief period of exponential expansion, as the cosmologist Alan Guth proposed in 1980, then quantum-size ripples would have stretched into huge, permanent undulations in the fabric of the universe. These gravitational waves would have stamped a swirl pattern, called “B-mode” polarization, in the cosmic microwave background, the oldest light now detectable in the sky.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

High-energy gamma ray bursts have 100-times the energy output of a supernova

High-energy gamma ray bursts have 100-times the energy output of a supernova | Amazing Science | Scoop.it

In the 1960s a series of satellites were built as part of Project Vela.  Project Vela was intended to detect violations of the 1963 ban on above ground testing of nuclear weapons.  The Vela satellites were designed to detect bursts of gamma rays, which are high energy electromagnetic waves produced by radioactive decay.  If any nuclear weapon was detonated in space, the resulting radioactive decay would release a large amount of gamma rays which would be detected by the Vela satellites.

In 1967, two of the Vela probes detected a large spike of gamma rays.  But the signature of this spike was very different from those of a nuclear explosion.  Soon more gamma ray spikes were detected, and these likewise differed from the expected signature of a nuclear test.  Since the bursts were observed by multiple satellites, the Vela team was able to compare the arrival of the bursts between different satellites, and it soon became clear that the bursts had an extraterrestrial source.  Of course the Vela project was classified, so it wasn't until 1973 that the results were declassified and published in Astrophysical Journal.  It was only then that astronomers were made aware of these gamma ray bursts (GRBs).


We now know that GRBs are very common.  On average, about one gamma ray burst occurs every day.   They appear randomly in all directions of the sky, and this means they aren't produced in our galaxy.  If they were, then GRBs would mostly be found along the plane of the Milky Way.


Some gamma ray bursts (known as long bursts) can last more than two seconds.  These bursts have afterglow caused by gamma rays colliding with interstellar material near the event, causing the emission of light at other wavelengths.  This afterglow allows us to measure the redshift of these events, and what we find is that they are quite distant.  The closest observed gamma ray burst occurred at a distance of 100 million light years, and many occurred billions of light years away.


We aren't entirely sure what causes a gamma ray burst.  Because of their distance, and apparent brightness, they must be extraordinarily energetic, with about 100 times more energy than a supernova.  They may be caused by huge supernova explosions known as hypernova, or they may be caused by supernova explosions occur with a rotational axis pointing in our direction, causing a jet-like burst of energy.  Short burst GRBs, lasting less than 2 seconds, may be due to collisions between neutron stars.


Given the huge energy of GRBs, one might wonder if one could occur in our galaxy.  Given the average rate of GRBs and the huge distances at which they typically occur, the rate at which one happens in our galaxy is probably about once every 5 million years.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Hubble Helps to Find Smallest Known Galaxy Containing a Supermassive Black Hole

Hubble Helps to Find Smallest Known Galaxy Containing a Supermassive Black Hole | Amazing Science | Scoop.it

Astronomers using data from NASA’s Hubble Space Telescope and ground observation have found an unlikely object in an improbable place -- a monster black hole lurking inside one of the tiniest galaxies ever known.


The black hole is five times the mass of the one at the center of our Milky Way galaxy. It is inside one of the densest galaxies known to date -- the M60-UCD1 dwarf galaxy that crams 140 million stars within a diameter of about 300 light-years, which is only 1/500th of our galaxy’s diameter.

If you lived inside this dwarf galaxy, the night sky would dazzle with at least 1 million stars visible to the naked eye. Our nighttime sky as seen from Earth’s surface shows 4,000 stars.


The finding implies there are many other compact galaxies in the universe that contain supermassive black holes. The observation also suggests dwarf galaxies may actually be the stripped remnants of larger galaxies that were torn apart during collisions with other galaxies rather than small islands of stars born in isolation.


“We don’t know of any other way you could make a black hole so big in an object this small,” said University of Utah astronomer Anil Seth, lead author of an international study of the dwarf galaxy published in Thursday’s issue of the journal Nature.


Seth’s team of astronomers used the Hubble Space Telescope and the Gemini North 8-meter optical and infrared telescope on Hawaii’s Mauna Kea to observe M60-UCD1 and measure the black hole’s mass. The sharp Hubble images provide information about the galaxy’s diameter and stellar density. Gemini measures the stellar motions as affected by the black hole’s pull. These data are used to calculate the mass of the black hole.


Black holes are gravitationally collapsed, ultra-compact objects that have a gravitational pull so strong that even light cannot escape. Supermassive black holes -- those with the mass of at least one million stars like our sun -- are thought to be at the centers of many galaxies.


The black hole at the center of our Milky Way galaxy has the mass of four million suns. As heavy as that is, it is less than 0.01 percent of the Milky Way’s total mass. By comparison, the supermassive black hole at the center of M60-UCD1, which has the mass of 21 million suns, is a stunning 15 percent of the small galaxy’s total mass.


“That is pretty amazing, given that the Milky Way is 500 times larger and more than 1,000 times heavier than the dwarf galaxy M60-UCD1,” Seth said.


One explanation is that M60-UCD1 was once a large galaxy containing 10 billion stars, but then it passed very close to the center of an even larger galaxy, M60, and in that process all the stars and dark matter in the outer part of the galaxy were torn away and became part of M60.


The team believes that M60-UCD1 may eventually be pulled to fully merge with M60, which has its own monster black hole that weighs a whopping 4.5 billion solar masses, or more than 1,000 times bigger than the black hole in our galaxy. When that happens, the black holes in both galaxies also likely will merge. Both galaxies are 50 million light-years away.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Astronomers observe a Thorne–Żytkow Object, where a neutron star appears to be inside a red giant star

Astronomers observe a Thorne–Żytkow Object, where a neutron star appears to be inside a red giant star | Amazing Science | Scoop.it

As all who study astronomy know, one of the most incredible things about the universe is the never-ending potential for wonderful discoveries that sound more like fiction than fact.  With this paper, the authors are pushing the boundaries of fiction into fact with the potential discovery of a new exotic object, known as a Thorne–Żytkow object (TZO).  First predicted in the 1970s by Kip Thorne and AnnaŻytkow, these bodies occur when a neutron star in a binary system with a red supergiant (RSG) merges into the second star.  This merger creates an unusual system where there is a neutron star surrounded by a large, diffuse envelope of material.  The system still produces most of its energy at the core of the material envelope through thermonuclear energy, and a smaller amount (about 5% of the total energy) from the gravitational accretion of material onto the neutron star.  Eventually, after several hundred years, the core of the envelope and the neutron star would merge, resulting in either a larger neutron star or a black hole.


TZOs are fascinating objects in a special state of a binary system’s evolution, and there is a lot of new physics that can be learned from such a system, but there has been one problem with them until now: they are identical in appearance to typical red supergiants.  There are a lot of normal red supergiants no matter where you look, and knowing if a RSG is a TZO is only possible when you look in detail at the stellar spectra for the over-abundance of lithium and other specific heavy metals.  Finding a TZO is definitely a “find the needle in a haystack” kind of observing problem!


Luckily for science, the authors successfully found the needle.  They did this by conducting a survey of stars in the Milky Way andMagellanic Clouds from previous stellar surveys where effective temperature and photometry data indicated a RSG.  The authors then took the stellar spectra of the 62 stars in their sample at Apache Point Observatory in New Mexico and the Magellan telescopes in Chile, and then analyzing the spectra for the ratios between elements in order to see whether there were any anomalies.  In one case, for a star known as HV 2112, in the Small Magellanic Cloud, and found it had unusually high concentrations of lithium, molybdenum, and rubidium.  These elements, especially in the amounts found in HV 2112, are indications the star is not a RSG at all, but rather a TZO.  Some spectral features were also observed that are not predicted in TZO models, but the authors aknowledge that available TZO models are older and do not take into account some recent advances in stellar convection modeling.


This TZO discovery, if confirmed from follow-up theoretical models, is exciting because HV 2112 would be the prototype of a whole new kind of system.  But beyond being a scientific curiousity, a TZO can provide a new environment for answering several questions, such as a new fate of massive binary systems.  Further, because this is a completely new kind of stellar interior, we are also looking at a different kind of stellar nuclear synthesis process for heavy metals than anything previously observed.  It is like being handed a new laboratory in which to test astrophysical ideas, and to distinguish the fact from fiction.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Hubble Finds Companion Star Hidden for 21 Years in a Supernova's Glare

Hubble Finds Companion Star Hidden for 21 Years in a Supernova's Glare | Amazing Science | Scoop.it

Astronomers using NASA's Hubble Space Telescope have discovered a companion star to a rare type of supernova. This observation confirms the theory that the explosion originated in a double-star system where one star fueled the mass-loss from the aging primary star.


This detection is the first time astronomers have been able to put constraints on the properties of the companion star in an unusual class of supernova called Type IIb. They were able to estimate the surviving star's luminosity and mass, which provide insight into the conditions that preceded the explosion.


"A binary system is likely required to lose the majority of the primary star's hydrogen envelope prior to the explosion. The problem is that, to date, direct observations of the predicted binary companion star have been difficult to obtain since it is so faint relative to the supernova itself," said lead researcher Ori Fox of the University of California (UC) at Berkeley.


Astronomers estimate that a supernova goes off once every second somewhere in the universe. Yet they don't fully understand how stars explode. Finding a "smoking gun" companion star provides important new clues to the variety of supernovae in the universe. "This is like a crime scene, and we finally identified the robber," quipped team member Alex Filippenko, professor of astronomy at UC Berkeley. "The companion star stole a bunch of hydrogen before the primary star exploded."


The explosion happened in the galaxy M81, which is about 11 million light-years away from Earth in the direction of the constellation Ursa Major (the Great Bear). Light from the supernova was first detected in 1993, and the object was designated SN 1993J. It was the nearest known example of this type of supernova, called a Type IIb, due to the specific characteristics of the explosion. For the past two decades astronomers have been searching for the suspected companion, thought to be lost in the glare of the residual glow from the explosion.


Observations made in 2004 at the W.M. Keck Observatory on Mauna Kea, Hawaii, showed circumstantial evidence for spectral absorption features that would come from a suspected companion. But the field of view is so crowded that astronomers could not be certain if the spectral absorption lines were from a companion object or from other stars along the line of sight to SN 1993J. "Until now, nobody was ever able to directly detect the glow of the star, called continuum emission," Fox said.


The companion star is so hot that the so-called continuum glow is largely in ultraviolet (UV) light, which can only be detected above Earth's absorbing atmosphere. "We were able to get that UV spectrum with Hubble. This conclusively shows that we have an excess of continuum emission in the UV, even after the light from other stars has been subtracted," said team member Azalee Bostroem of the Space Telescope Science Institute (STScI), in Baltimore, Maryland.

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Scientist uncovers Mars' climate history in unique meteorite known as Black Beauty

Scientist uncovers Mars' climate history in unique meteorite known as Black Beauty | Amazing Science | Scoop.it

Research underway at the National High Magnetic Field Laboratory may one day answer those questions — and perhaps even help pave the way for future colonization of the Red Planet. By analyzing the chemical clues locked inside an ancient Martian meteorite known as Black Beauty, Florida State University Professor Munir Humayun and an international research team are revealing the story of Mars’ ancient, and sometimes startling, climate history.


The team’s most recent finding of a dramatic climate change appeared in Nature Geoscience, in the paper “Record of the ancient Martian hydrosphere and atmosphere preserved in zircon from a Martian meteorite.”


The scientists found evidence for the climate shift in minerals called zircons embedded inside the dark, glossy meteorite. Zircons, which are also abundant in the Earth’s crust, form when lava cools. Among their intriguing properties, Humayun says, is that “they stick around forever.”

“When you find a zircon, it’s like finding a watch,” Humayun said. “A zircon begins keeping track of time from the moment it’s born.”


Last year, Humayun’s team correctly determined that the zircons in its Black Beauty sample were an astonishing 4.4 billion years old. That means, Humayun says, it formed during the Red Planet’s infancy and during a time when the planet might have been able to sustain life.


“First we learned that, about 4.5 billion years ago, water was more abundant on Mars, and now we’ve learned that something dramatically changed that,” said Humayun, a professor of geochemistry. “Now we can conclude that the conditions that we see today on Mars, this dry Martian desert, must have persisted for at least the past 1.7 billion years. We know now that Mars has been dry for a very long time.”

more...
No comment yet.
Scooped by Dr. Stefan Gruenwald
Scoop.it!

Seth Shostak, leading expert at SETI, is optimistic about finding signs of extraterrestrial life this century

Seth Shostak, leading expert at SETI, is optimistic about finding signs of extraterrestrial life this century | Amazing Science | Scoop.it

We are going to find life in space in this century,' Dr. Seth Shostak, Senior Astronomer at the Search for Extra-Terrestrial Intelligence Institute (SETI) said emphatically at the European Commission Innovation Convention. 'There are 150 billion galaxies other than our own, each with a few tens of billions of earth-like planets. If this is the only place in the universe where anything interesting happening then this is a miracle. And 500 years of astronomy has taught us that whenever you believe in a miracle, you're probably wrong.'


How will discover life in space? Dr Shostak sees it as a 'three-horse race' which will probably be won over the next 25 years. We will either find it nearby, in microbial form, on Mars or one of the moons of Jupiter; we will find evidence for gases produced by living processes (for example photosynthesis) in the atmospheres of planets around other stars; or Dr Shostak and his team at SETI will pick up signals from intelligent life via huge antennas.


Dr. Suzanne Aigrain, Lecturer in Astrophysics at Oxford University, who studies extrasolar planets or exoplanets (planets around other stars than the sun), represents horse number two in the race. Speaking at the Convention, Dr Aigrain noted that, based on her studies, she would also bet that we are not alone. 'We are very close to being able to say with a good degree of certainty that planets like the Earth, what we call habitable planets, are quite common in the universe. That's why when asked if I believe there's life on other planets, I raise my hand and I do so as a scientist because the balance of probability is overwhelmingly high.'


Dr. Aigrain, and the groups that she works with, have so far been using light - electromagnetic radiation - as their primary tool to look for planets around stars other than the sun. Habitable planets are defined as those that are roughly the size of the earth where the surface temperature is suitable for liquid water to exist on the surface. The life 'biomarkers' that Dr. Aigrain and her colleagues look for are trace gases in the atmospheres of the exoplanets that they think can only be there if they are being produced by a biological source like photosynthesis.


Dr Shostak and SETI, meanwhile, seek evidence of life in the universe by looking for some signature of its technology. If his team does discover radio transmissions from space, Dr Shostak is quite certain that they will be coming from a civilisation more advanced than our own. 'Why do I insist that if we find ET, he/she/it will be more advanced than we are? The answer is that you're not going to hear the Neanderthals. The Neanderthal Klingons are not building radio transmitters that will allow you to get in touch.'


If we do find life on other planets or intercept a radio signal, what are the consequences? Finding a microbe that isn't an earthly microbe will tell us a lot about biology, but there will also be huge philosophical consequences. In Dr Shostak's words, 'It literally changes everything.'

more...
CineversityTV's curator insight, September 3, 2014 9:36 PM

it seems they are way behind in science

Scooped by Dr. Stefan Gruenwald
Scoop.it!

For the first time, our region of the universe has a map and a name: Laniakea

For the first time, our region of the universe has a map and a name: Laniakea | Amazing Science | Scoop.it

Scientists have redrawn the cosmic map of our corner of the universe, using new tools to define which galaxies interact with our own. The so-called supercluster of galaxies that contains the Milky Way has been named "Laniakea," which means "immense heaven" in Hawaiian.


Defining regions in an infinite universe is tricky business: Clusters of dozens of galaxies, called local groups, are further bound into clusters containing hundreds of galaxies. The Laniakea supercluster, described in apaper published in this week's Nature, is 500 million light-years in diameter and contains 100,000 galaxies - and we sit at the very edge of it. Together, those galaxies carry 100 million billion times the mass of our sun.


How can such a massive number of galaxies be connected? While some areas of space are basically empty, others contain highly concentrated star power. In these areas, the supercluster galaxies are drawn toward each other in intricate ways. According to R. Brent Tully, an astronomer at the University of Hawaii at Manoa and lead author of the study, galaxies in the cosmos can be compared to water on Earth.


In the new study, Tully and his colleagues provide our first clear definition of a supercluster. By mapping the flow of over 8,000 galaxies that surround our own, they figured out where the clusters diverged. In other words, they pinpointed at what point galaxies started to be drawn toward a different "valley" than we are.


It's possible that scientists will eventually map out a cluster that's even more super. "We've found the local region, but we already see that our base of attraction is actually being pulled toward another base of attraction," Tully said. "We don't really understand why."

more...
No comment yet.