| | 10 new stories for 2016/04/19
Antarctica Provides Plenty Of Mars Samples Right Now 
Sometimes, the best way to study Mars is to stay home. There's no substitute for actual missions to Mars, but pieces of Mars have made the journey to Earth, and saved us the trip. Case in point: the treasure trove of Martian meteorites that NASA is gathering from Antarctica.NASA scientists aren't the first ones to find meteorites in the Earth's polar regions. As early as the 9th century, people in the northern polar regions made use of iron from meteorites for tools and hunting weapons. The meteorite iron was traded from group to group over long distances. But for NASA, the hunt for meteorites is focused on Antarctica.In Antarctica, the frigid temperatures preserve meteorites for a long time, which makes them valuable artifacts in the quest to understand Mars. Meteorites tend to accumulate in places where creeping glacial ice moves them to. When the ice meets a rock obstacle, the meteorites are deposited there, making them easier to find. Recently arrived meteorites are also easily spotted on the surface of the Antarctica ice.[embed]https://www.youtube.com/watch?v=60w3WbVwhh8[/embed]The US began collecting meteorites in Antarctica in 1976, and to date more than 21,000 meteorites and meteorite fragments have been found. In fact, more of them are found in Antarctica than in the rest of the world combined. These meteorites are then shared with scientists around the world.Collecting meteorites in Antarctica is not a walk in the park. It's physically gruelling and hazardous work. Antarctica is not an easy environment to live and work in, and just surviving there takes planning and teamwork. But the scientific payoff is huge, which keeps NASA going back.Meteorites from the Moon and other bodies also arrive on Earth, and are collected in Antarctica. They can tell scientists important things about the evolution and formation of the Solar System, the origin of organic chemical compounds necessary for life, and the origin of the planets themselves. How Do Martian Meteorites Get To Earth?A few things have to go right for a Martian meteorite to make it to Earth. First, a meteorite has to collide with Mars. That meteorite has to be big enough, and hit the surface of Mars with enough force, that rock from Mars is propelled off the surface with enough speed to escape Mars' gravity.[embed]https://www.youtube.com/watch?v=oZNSszq9O-g[/embed]After that, the meteor has to travel through space and avoid a thousand other fates, like being drawn to one of the other planets, or the Sun, by the gravitational pull of those bodies. Or being flung off into the far reaches of empty space, lost forever. Then, if it manages to make it to Earth, and be pulled in by Earthly gravity, it must be large enough to survive entry into Earth's atmosphere. The SciencePart of the scientific value in meteorites lies not in their source, but in the time that they were formed. Some meteorites have travelled through space for so long, they're like time travellers. These ancient meteorites can tell scientists a lot about conditions in the early Solar System.Meteorites from Mars tell scientists a few things. Since they've survived re-entry into Earth's atmosphere, they can tell engineers about the dynamics of such a journey, and help inform spacecraft design. Since they contain chemical signatures and elements unique to Mars, they can also tell mission specialists things about surviving on Mars.They can also provide clues to one of the greatest mysteries in space exploration: Did life exist on Mars? A Martian meteorite found in the Sahara desert in 2011 contained ten times the amount of water as other Martian meteorites, and added evidence to the idea that Mars was once a wet world, suitable for life.NASA's program to hunt for meteorites in Antarctica has been going strong for many years, and there's really no reason to stop doing it, since this is the only way to get Martian samples into a laboratory. Each one they find is like a puzzle piece, and like a jigsaw puzzle, you never know which one will complete the big picture. The post Antarctica Provides Plenty Of Mars Samples Right Now appeared first on Universe Today.
Dwarf Dark Matter Galaxy Hides In Einstein Ring 
Everybody knows that galaxies are enormous collections of stars. A single galaxy can contain hundreds of billions of them. But there is a type of galaxy that has no stars. That's right: zero stars.These galaxies are called Dark Galaxies, or Dark Matter Galaxies. And rather than consisting of stars, they consist mostly of Dark Matter. Theory predicts that there should be many of these Dwarf Dark Galaxies in the halo around 'regular' galaxies, but finding them has been difficult.Now, in a new paper to be published in the Astrophysical Journal, Yashar Hezaveh at Stanford University in California, and his team of colleagues, announce the discovery of one such object. The team used enhanced capabilities of the Atacamas Large Millimeter Array to examine an Einstein ring, so named because Einstein's Theory of General Relativity predicted the phenomenon long before one was observed.An Einstein Ring is when the massive gravity of a close object distorts the light from a much more distant object. They operate much like the lens in a telescope, or even a pair of eye-glasses. The mass of the glass in the lens directs incoming light in such a way that distant objects are enlarged.Einstein Rings and gravitational lensing allow astronomers to study extremely distant objects, by looking at them through a lens of gravity. But they also allow astronomers to learn more about the galaxy that is acting as the lens, which is what happened in this case.If a glass lens had tiny water spots on it, those spots would add a tiny amount of distortion to the image. That's what happened in this case, except rather than microscopic water drops on a lens, the distortions were caused by tiny Dwarf Galaxies consisting of Dark Matter. "We can find these invisible objects in the same way that you can see rain droplets on a window. You know they are there because they distort the image of the background objects," explained Hezaveh. The difference is that water distorts light by refraction, whereas matter distorts light by gravity.As the ALMA facility increased its resolution, astronomers studied different astronomical objects to test its capabilities. One of these objects was SDP81, the gravitational lens in the above image. As they examined the more distant galaxy being lensed by SDP81, they discovered smaller distortions in the ring of the distant galaxy. Hezaveh and his team conclude that these distortions signal the presence of a Dwarf Dark Galaxy.[embed]https://vimeo.com/158971342[/embed]But why does this all matter? Because there is a problem in the Universe, or at least in our understanding of it; a problem of missing mass.Our understanding of the formation of the structure of the Universe is pretty solid, at least in the larger scale. Predictions based on this model agree with observations of the Cosmic Microwave Background (CMB) and galaxy clustering. But our understanding breaks down somewhat when it comes to the smaller scale structure of the Universe.One example of our lack of understanding in this area is what's known as the Missing Satellite Problem. Theory predicts that there should be a large population of what are called sub-halo objects in the halo of dark matter surrounding galaxies. These objects can range from things as large as the Magellanic Clouds down to much smaller objects. In observations of the Local Group, there is a pronounced deficit of these objects, to the tune of a factor of 10, when compared to theoretical predictions.Because we haven't found them, one of two things needs to happen: either we get better at finding them, or we modify our theory. But it seems a little too soon to modify our theories of the structure of the Universe because we haven't found something that, by its very nature, is hard to find. That's why this announcement is so important.The observation and identification of one of these Dwarf Dark Galaxies should open the door to more. Once more are found, we can start to build a model of their population and distribution. So if in the future more of these Dwarf Dark Galaxies are found, it will gradually confirm our over-arching understanding of the formation and structure of the Universe. And it'll mean we're on the right track when it comes to understanding Dark Matter's role in the Universe. If we can't find them, and the one bound to the halo of SDP81 turns out to be an anomaly, then it's back to the drawing board, theoretically.It took a lot of horsepower to detect the Dwarf Dark Galaxy bound to SDP81. Einstein Rings like SDP81 have to have enormous mass in order to exert a gravitational lensing effect, while Dwarf Dark Galaxies are tiny in comparison. It's a classic 'needle in a haystack' problem, and Hezaveh and his team needed massive computing power to analyze the data from ALMA.ALMA, and the methodology developed by Hezaveh and team will hopefully shed more light on Dwarf Dark Galaxies in the future. The team thinks that ALMA has great potential to discover more of these halo objects, which should in turn improve our understanding of the structure of the Universe. As they say in the conclusion of their paper, "... ALMA observations have the potential to significantly advance our understanding of the abundance of dark matter substructure." The post Dwarf Dark Matter Galaxy Hides In Einstein Ring appeared first on Universe Today.
'Wow!' Signal Was…Wait For It…Comets 
Comets get blamed for everything. Pestilence in medieval Europe? Comets! Mass extinctions? Comets! Even the anomalous brightness variations in the Kepler star KIC 8462852 was blamed for a time on comets. Now it looks like the most famous maybe-ET signal ever sifted from the sky, the so-called "Wow!" signal, may also be traced to comets.Say it ain't so!In August 1977, radio astronomer Jerry Ehman was looking through observation data from the Ohio State's now-defunct Big Ear radio telescope gathered a few days earlier on August 15. He was searching for signals that stood apart from the background noise that might be broadcast by an alien civilization. Since hydrogen is the most common element in the universe and emits energy at the specific frequency of 1420 megahertz (just above the TV and cellphone bands), aliens might adopt it as the "lingua franca" of the cosmos. Scientists here on Earth concentrated radio searches at and around that frequency looking for strong signals that mimicked hydrogen.Ehman's searches turned up mostly background noise, but that mid-August night he spotted a surprise — a vertical column with the alphanumerical sequence "6EQUJ5" that indicated a strong signal at hydrogen's frequency. Exactly as predicted. Big Ear picked up the signal from near the 5th magnitude star Chi-1 Sagittarii in eastern Sagittarius not far from the globular cluster M55.Astonished by the find, Ehman pulled out a red pen, circled the sequence and wrote a big "Wow!" in the margin. Ever since, it's been called the Wow! signal and considered one of the few signals from space that defies explanation. Before we look at how that may change, let's make sense of the code.Each digit on the chart corresponded to a signal intensity from 0 to 35. Anything over "9" was represented by a letter from A to Z. It was probably the "U" that knocked Ehman's socks off, since it indicated to a radio burst 30 times greater than the background noise of space.In Big Ear's 35 years of operation, it was the most intense, unexplainable signal ever recorded. What's more, it was narrowly focused and very close to hydrogen's special frequency.Big Ear listened for just 72 seconds before Earth's rotation carried the signal's location out of "view" of antenna. Since the radio array had two feed horns, the transmission was expected to appear three minutes apart in each of the horns, but only a single one ever picked it up.Despite follow-up observations by Ehman and others (more than 100 studies were made of the region) the signal was gone. Never heard from again. Nor has anything else like it ever been recorded anywhere else in the sky.Careful scrutiny eliminated earthbound possibilities such as aircraft or satellites. Nor would anyone have been transmitting at 1420 MHz since it was within a protected part of the radio spectrum used by astronomers and off-limits to regular broadcasters. The nature of the signal implied a point source somewhere beyond the Earth. But where?If it really was an attempt at alien contact, why try only once and for so short a time interval? Even Ehman doubted (and still doubts) an extraterrestrial intelligence origin, but a much more recent suggestion made by Prof. Antonio Paris of St. Petersburg College, Florida may offer an answer. Paris earlier worked as an analyst for the U.S. Department of Defense and returned to the "scene of the crime" looking for any likely suspects. After studying astronomical databases, he discovered that two faint comets, 266P/Christensen and 335P/Gibbs, discovered only within the past decade, had been plying the very area of the Wow! signal on August 15, 1977.If you recall, a comet has two or three basic parts: a fuzzy head or coma and one or two tails streaming off behind. Invisible to earthbound telescopes, but showing clearly in orbiting telescopes able to peer into ultraviolet light, the coma is further wrapped in a huge cloud of neutral hydrogen gas.As the Sun warms a comet's surface, water ice or H2O vaporizes from its nucleus. Energetic solar UV light breaks down those water molecules into H2 and O. The H2 forms a huge, distended halo that can expand to many times the size of the Sun.Paris published a paper earlier this year exploring the possibility that the hydrogen envelopes of either or both comets were responsible for the strong 1420 MHz signal snagged by Big Ear. On the surface, this makes sense, but not all astronomers agree. First off, if comets are so radio-bright in hydrogen light, why don't radio telescopes pick them up more often? They don't. Second, some astronomers doubt that the signals from these comets would have been strong enough to be picked up by the array.A quick check on 266P and 335P at the time of the signal show them both around 5 a.u. from the sun (Jupiter's distance) and extremely faint at magnitudes 22 and 27 respectively. Were they even active enough at those distances to form clouds big enough for the antenna to detect?Paris knows there's only one way to find out. Comet 266P/Christensen will swing through the same area again on Jan. 25, 2017, while 335P/Gibbs follows suit on January 7, 2018. Unable to use an existing radio telescope (they're all booked up!), he's begun a gofundme campaign to purchase and install a 3-meter radio telescope to track and analyze the spectra of these two comets. The goal is $20,000 and Paris is already well on his way there.It would be a little bit sad if the Wow! signal turned out to be a "just a comet", but the possibility of solving a 39-year-old mystery would ultimately be more satisfying, don't you think? The post 'Wow!' Signal Was…Wait For It…Comets appeared first on Universe Today.
Space Station Gets Experimental New Room with Installation of BEAM Expandable Habitat 
The International Space Station (ISS) grew in size today, April 16, following the successful installation of an experimental new room - the BEAM expandable habitat module.Engineers at NASA's Johnson Space Center in Houston used the space station's high tech robotic arm to pluck the small module known as the Bigelow Expandable Activity Module (BEAM) out from the unpressurized rear truck section of the recently arrived SpaceX Dragon cargo freighter, and added it onto the orbiting laboratory complex.BEAM was manufactured by Las Vegas-based Bigelow Aerospace under a $17.8 million contract with NASA. It will remain joined to the station for at least a two-year test period.The 3115 pound (1413 kg) BEAM will test the use of an expandable space habitat in microgravity with humans for the first time.It was extracted from the Dragon's trunk overnight with the robotic Canadarm2 and then installed on the aft port of the Tranquility module at 5:36 a.m. EDT over a period of about 4 hours. The station was flying over the Southern Pacific Ocean at the moment of berthing early Saturday.NASA astronaut and ISS Expedition 47 crew member Tim Kopra snapped a super cool photo of BEAM in transit, shown above.BEAM was carried to orbit in a compressed form inside the Dragon's truck following the April 8 blast off from Cape Canaveral Air Force Station at 4:43 p.m. EDT on the Dragon CRS-8 resupply mission for NASA to the ISS. BEAM is a prototype inflatable habitat that could revolutionize the method of construction of future habitable modules intended for use both in Low Earth Orbit (LEO) as well as for deep space expeditions Beyond Earth Orbit (BEO) to destinations including the Moon, Asteroids and Mars.The advantage of expandable habitats is that they offer a much better volume to weight ratio compared to standard rigid metallic structures such as all of the current ISS pressurized modules.It is constructed of lighter weight reinforced fabric rather that metal. This counts as the first test of an expandable module and investigators want to determine how it fares with respect to protection again solar radiation, space debris and the temperature extremes of space.Furthermore they also take up much less space inside the payload fairing of a rocket during launch.Watch this animation showing how Canadarm2 transports BEAM from the Dragon spacecraft to a side berthing port on Tranquility where it will soon be expanded.Current plans call for the module to be expanded in late May with air. It will expand to nearly five times from its compressed size of 8 feet in diameter by 7 feet in length to roughly 10 feet in diameter and 13 feet in length. Once inflated it will provide 565 cubic feet (16 m3) of habitable volume.Exactly how it will expand is also an experiment and could happen in multiple ways. Therefore the team will exercise great caution and carefully monitor the inflation and check for leaks.The astronauts will first enter BEAM about a week after the expansion. Thereafter they will visit it about 2 or 3 times per year for several hours to retrieve sensor data and assess conditions, say NASA officials.Visits could perhaps occur even frequently more if NASA approves. says Bigelow CEO Robert Bigelow.BEAM is an extraordinary test bed in itself.But Robert Bigelow hopes that BEAM can be used to conduct science experiments after maybe a six month shakedown cruise, if all goes well, and NASA approves a wider usage.Bigelow Aerospace has already taken in the next step in expandable habitats. Earlier this week, Bigelow and rocket builder United Launch Alliance (ULA) announced they are joining forces to develop and launch the B330 expandable commercial habitat module in 2020 on an Atlas V. It is about 20 times larger and far more capable. Details in my story here.Robert Bigelow says he hopes that NASA will approve docking of the B330 at the ISS.The SpaceX Dragon spacecraft delivered almost 7,000 pounds of cargo.CRS-8 counts as the company's eighth flight to deliver supplies, science experiments and technology demonstrations to the ISS for the crews of Expeditions 47 and 48 to support dozens of the approximately 250 science and research investigations in progress.Stay tuned here for Ken's continuing Earth and planetary science and human spaceflight news. Ken Kremer………….Learn more about SpaceX, NASA Mars rovers, Orion, SLS, ISS, Orbital ATK, ULA, Boeing, Space Taxis, NASA missions and more at Ken's upcoming outreach events:Apr 17: "NASA and the Road to Mars Human Spaceflight programs"- 1:30 PM at Washington Crossing State Park, Nature Center, Titusville, NJ - http://www.state.nj.us/dep/parksandforests/parks/washcros.html The post Space Station Gets Experimental New Room with Installation of BEAM Expandable Habitat appeared first on Universe Today.
Is Alpha Centauri The Best Place To Look For Aliens? 
For generations, human beings have fantasized about the possibility of finding extra-terrestrial life. And with our ongoing research efforts to discover new and exciting extrasolar planets (aka. exoplanets) in distant star systems, the possibility of actually visiting one of these worlds has received a real shot in the arm. Unfortunately, given the astronomical distances involved, not to mention the cost of mounting an expedition, doing so presents numerous significant challenges.However, Russian billionaire Yuri Milner and the Breakthrough Foundation - an international organization committed to exploration and scientific research - is determined to mount an interstellar mission to Alpha Centauri, our closest stellar neighbor, in the coming years. With the backing of such big name sponsors as Mark Zuckerberg and Stephen Hawking, his latest initiative (named " Project Starshot") aims to send a tiny spacecraft to the Alpha Centauri system to search for planets and signs of life. Consisting of an ultra-light nanocraft and a lightsail, the concept calls for a ground-based laser array to push the lightsail up to speeds of hundreds of kilometers a second, towing the nanocraft into deep space. Such a system would allow the tiny spacecraft to conduct a flyby mission to Alpha Centauri in about 20 years after it is launched, which could then beam home images of possible planets, as well as other scientific data such as analysis of magnetic fields.In essence, Starshot seeks to leverage recent technological developments to mount an interstellar mission that will reach another star within a single generation. As we explained in another article (" How Long Would It Take To Travel To The Nearest Star?"), using existing technology, it would take between 19,000 to 81,000 years for a spacecraft to make the trip to even the nearest star, depending on whether chemical rockets or ion engines were used.Hence, the Foundation's advisory board explored all potential methods for creating a craft that could travel at relativistic speeds - up to 20% the speed of light - so it could traverse the 4.37 light year distance in just 20 years. They determined that a tiny craft, roughly the size of a refrigerator magnet and weighing in the vicinity of a few grams, would be the best model for a spacecraft. They further determined that the best propulsion method would be laser-driven lightsail, which is not hampered by the limits of conventional methods.With a massive ground-based laser directing the sail, the plan is to accelerate the nanocraft to its terminal velocity before it reaches a distance of about one million km from Earth (which is the limit to which the laser beam can be focused on the meter-scale sail). All told, the nanocraft will experience an acceleration of about 60,000 g (sixty-thousands times the force of Earth's gravity, which works out to just under 600,000 m/s²).As Professor Avi Loeb, the Frank B. Baird, Jr. Professor of Science at Harvard University and chairman of the Foundation's Advisory Board, explained to Universe Today via email: "{O]nly one offers a path forward: using beamed (laser) light to push a sail attached to a lightweight (gram-scale) smart payload (with a camera, transmitter and thrusters). This approach benefits from two major technological advances that were realized recently: miniaturization of electronics (developed by the cell phone industry) and the construction arrays of lasers that combine to make a very powerful and focused beam of light (developed by the defense industry). Interstellar travel is challenging, but based on these technological advances, we believe that there is a path forward without obvious show stoppers. The project is ambitious but doable." In addition to accomplishing the dream of countless generations (i.e. traveling to another star system), Breakthrough Starshot hopes to generate important supplementary benefits to astronomy in the meantime. Much like the Apollo Program of the 1960s, the Breakthrough Starshot program hopes to stimulate the development of technologies that will be beneficial here on Earth.These include demonstrating proof-of-concept technology that will enable the exploration the solar system, the detection and study of Near Earth Objects (NEOs), and the benefits to material science that solar sail development will bring. The development of laser arrays will also have major implications for the science of optical systems, and the laser communication devices used on Starshot will likely lead to better communication with airplanes and satellites around Earth.As Pete Worden, the Executive Director Project Breakthrough StarShot, told Universe Today via email: "The project goals are to develop and demonstrate the technologies, particularly with respect to high power laser beaming technology and gram-class lightsail-craft that could enable humanity to send these craft to the nearest star system, Alpha Centauri within a generation. We hope to mobilize the world's expertise to make this possible. The program will be an open international program. Yuri Milner has provided our initial funding. Renowned physicist Stephen Hawking and Facebook founder Mark Zuckerberg have joined Yuri Milner as the governing board of the project." Based on the Foundation's best estimates, this project could achieve its goal of dispatching their interstellar traveler within a few decades time. And with a 20 some-odd year transit time, we could be gaining vital information about the nearest star system (including whether or not it has life-supporting exoplanets) by the 2050s or 2060s.Naturally, there are still several engineering hurdles that would need to be overcome before Starshot can become a reality. For example, propelling a gram-scale spacecraft to 20% the speed of light will require a laser beam of that could generate about 100 Gigawatts of power over the course of a few minutes. The Project intends to build this laser array on the ground, simply because that would be much cheaper than building one in space.This, in turn, creates the challenge of optical-blurring due to atmospheric turbulence. Using adaptive optics (measuring atmospheric effects and correcting for them) is believed to be able to compensate for that. Such a method has been tested on the scale of the largest telescopes (10 meters in diameter), but would need to be tested on a scale of 1 km before it can be considered feasible.What's more, there are plenty of doubts as to the missions intended target, not to mention the likelihood that the mission will succeed. For instance, while Alpha Centauri may be the nearest star, thus making it the natural choice for interstellar exploration, there is little reason to suspect we will find any exoplanets there.Years back, astronomers announced the detection of a possible planet circling Alpha Centauri B with an orbital period of 3.24 days - which was named Alpha Cen Bb. However, subsequent examinations revealed that the detection of this exoplanet was the result of the window function (time sampling) of the original data. If we hope to find exoplanets, then we might need to look further afield - like Epsilon Eridani, a mere 10.5 light years away (which would result in a travel time of 55 years for the proposed nanocraft).And, as Paul Gilster of Centauri Dreams points out, the concept presents numerous challenges that will require technical advances not currently in existence. For example, beyond the issue of laser power and adaptive optics, there are issues with the sail concept itself that are likely to prove difficult. Essentially, this comes down to the need for a balance to be struck between powerful lasers and a sail that is capable of withstanding them: "Moreover, we have to design a sail that will 'ride' the beam rather than be blown off it, and one that will be so highly reflective that it will absorb less than 1/100,000th of the energy applied to it. These are problems that Robert Forward faced with his Starwisp design, a kilometer-wide 'spider web' of a sail driven by microwaves, with sensors scattered throughout the sail itself. It was Geoffrey Landis who would go on to show that as described, Starwisp would likely vaporize under the powerful beam meant to drive it to Alpha Centauri, causing a flurry of re-thinking of sail materials and design. But leaving the fuel at home is a powerful technique, and advances in technology may get us to the kind of materials that can withstand the photon torrent." Addressing the design called for by Breakthrough Starshot - a thin, round disc that is about the size of a picnic table in diameter, and which would have its entire electronics suite in the center - Gilster sees additional problems. "We've also got a problem in that concept," he says, "because Jim Benford has pointed out that a flat sail is not a good 'beam-rider' - we'll likely have to look at the kind of curved sail designs both Jim and brother Gregory Benford have studied in lab work at the Jet Propulsion Laboratory."In the end, the only reason to send a probe to Alpha Centauri is because of its proximity. And mounting the mission will require that the Breakthrough Foundation and its supporters come up with new and innovative solutions to the hurdles they face. But given that the opportunities for research and exploration will still be abundant, the reasonable timelines involved, and the likelihood of success, the mission certainly appears to be doable.Previous efforts by the Breakthrough Foundation's include Breakthrough Listen, the largest scientist research program aimed at detecting transmissions from distant stars. These include monitoring for radio transmissions and optical laser transmissions using advanced instruments that are significantly more sensitive than anything currently in use, combined with advanced software and data analysis. The program will span 10 years and cost an estimated $100 million, surveying the 1,000,000 closest stars to Earth and the 100 closest galaxies to the Milky Way.There's also Breakthrough Message, a $1 million competition aimed at encouraging a global debate about the ethics and possible methods of communicating with possible intelligent beings beyond Earth. The competition is open, and the prize will be awarded to anyone who is able to design a message (in digital format) that best represents Earth and humanity to other civilizations.And be sure to enjoy this video from the Breakthrough Foundation that illustrates the mission concept:https://youtu.be/RoCm6vZDDiQ Further Reading: Breakthrough InitiativesThe post Is Alpha Centauri The Best Place To Look For Aliens? appeared first on Universe Today.
Sensational Photos Show 'Super Smooth' Droneship Touchdown of SpaceX Falcon 9 Booster – SpaceX VP 
SpaceX has released a slew of up close photos showing the sensational "super smooth" touchdown last week of a Falcon 9 booster on a tiny droneship at sea located several hundred miles (km) off the East coast of Florida."This time it really went super smooth," Hans Koenigsmann, SpaceX VP of Flight Reliability, told Universe Today at the NorthEast Astronomy and Space Forum (NEAF) held in Suffern, NY. "The rest is history almost."The dramatic propulsive descent and soft landing of the SpaceX Falcon 9 first stage took place last Friday, April 8 about 9 minutes after blasting off from Cape Canaveral Air Force Station at 4:43 p.m. EDT on the Dragon CRS-8 resupply mission for NASA to the International Space Station (ISS).The breathtaking new photos show the boosters central Merlin 1D engine refiring to propulsively slow the first stage descent with all four landing legs unfurled and locked in place at the bottom and all four grid fins deployed at the top.Why did it all go so well, comparing this landing to the prior attempts? Basically the return trajectory was less challenging due to the nature of the NASA payload and launch trajectory."We were more confident about this droneship landing," Koenigsmann told me at NEAF."I knew the trajectory we had [for CRS-8] was more benign, although not super benign. But certainly benigner than for what we had before on the SES-9 mission, the previous one. The [droneship] landing trajectory we had for the previous one on SES-9 was really challenging.""This one was relatively benign. It was really maybe as benign as for the Orbcomm launch [in December 2015] where we had the land landing."Read my Orbcomm story here about history's first ever successful land landing of a spent SpaceX Falcon 9 booster. The diminutive ocean landing platform measures only about 170 ft × 300 ft (52 m × 91 m). SpaceX formally dubs it an 'Autonomous Spaceport Drone Ship' or ASDS.The ocean going ship is named "Of Course I Still Love You" after a starship from a novel written by Iain M. Banks. It was stationed some 200 miles off shore of Cape Canaveral, Florida surrounded by the vastness of the Atlantic Ocean."The CRS-8 launch was one of the easiest ones we ever had."The revolutionary rocket recovery event counts as the first successful droneship landing of a rocket in history and is paving the way towards eventual rocket recycling aimed at dramatically slashing the cost of access to space.The final moments of the 15 story tall boosters approach and hover landing was captured up close in stunning high resolution imagery recorded by multiple remote cameras set up right on the ocean going platform by SpaceX photographer Ben Cooper.Landing the booster on land rather than at sea was actually an option this time around. But SpaceX managers wanted to try and nail a platform at sea landing to learn more and validate their calculations and projections."As Elon Musk said at the post-landing press conference of Friday, we could have actually come back to land- to land this one on land," Koenigsmann elaborated."But we decided to land on the drone ship first to make sure that on the droneship we had worked everything out!""And that's exactly what happened. So I felt this was only going out a little bit on the limb," but not too much."Before the CRS-8 launch, Koenigsmann had rated the chances of a successful landing recovery rather high. Three previous attempts by SpaceX to land on a droneship at sea were partially successful, as the stage made a pinpoint flyback to the tiny droneship, but it either hit too hard or tipped over in the final moments when a landing leg failed to fully deploy or lock in place. "Everything went perfect with the launch," Koengismann said. "We just still have to do the post launch data review.""I am really glad this went well."This recovered Falcon 9 booster finally arrived back into Port Canaveral, Florida four days later in the early morning hours of Tuesday, April 12 at about 1:30 a.m. EDT.The primary goal of the Falcon 9 launch on April 8 was carrying the SpaceX Dragon CRS-8 cargo freighter to low Earth orbit on a commercial resupply delivery mission for NASA to the International Space Station (ISS).Dragon arrived at the station on Sunday, April 10, loaded with 3 tons of supplies, science experiments and the BEAM experimental expandable module.Landing on the barge was a secondary goal of SpaceX and not part of the primary mission for NASA.Watch this launch video from my video camera placed at the pad:https://youtu.be/DDzRWoz_xFM Video Caption: Spectacular blastoff of SpaceX Falcon 9 rocket carrying Dragon CRS-8 cargo freighter bound for the International Space Station (ISS) from Space Launch Complex 40 on Cape Canaveral Air Force Station, FL at 4:43 p.m. EST on April 8, 2016. Up close movie captured by Mobius remote video camera placed at launch pad. Credit: Ken Kremer/kenkremer.comThe recovered booster will be cleaned and defueled, says SpaceX spokesman John Taylor.SpaceX engineers will conduct a series of 12 test firings to ensure all is well operationally and that the booster can be re-launched.SpaceX hopes to refly the recovered booster in a few months, perhaps as early as this summer.Stay tuned here for Ken's continuing Earth and planetary science and human spaceflight news. Ken Kremer………….Learn more about SpaceX, NASA Mars rovers, Orion, SLS, ISS, Orbital ATK, ULA, Boeing, Space Taxis, NASA missions and more at Ken's upcoming outreach events:Apr 17: "NASA and the Road to Mars Human Spaceflight programs"- 1:30 PM at Washington Crossing State Park, Nature Center, Titusville, NJ - http://www.state.nj.us/dep/parksandforests/parks/washcros.html The post Sensational Photos Show 'Super Smooth' Droneship Touchdown of SpaceX Falcon 9 Booster – SpaceX VP appeared first on Universe Today.
Icy Hot: Europa's Frozen Crust Could Be Warmer Than We Thought 
All the worlds may be ours except Europa but that only makes the ice-covered moon of Jupiter all the more intriguing. Beneath Europa's thin crust of ice lies a tantalizing global ocean of liquid water somewhere in the neighborhood of 100 kilometers deep—which adds up to more liquid water than is on the entire surface of the Earth. Liquid water plus a heat source(s) to keep it liquid plus the organic compounds necessary for life and...well, you know where the thought process naturally goes from there.And now it turns out Europa may have even more of a heat source than we thought. Yes, a big component of Europa's water-liquefying warmth comes from tidal stresses enacted by the massive gravity of Jupiter as well as from the other large Galilean moons. But exactly how much heat is created within the moon's icy crust as it flexes has so far only been loosely estimated. Now, researchers from Brown University in Providence, RI and Columbia University in New York City have modeled how friction creates heat within ice under stress, and the results were surprising. Although 3,100-km-wide Europa is coated in ice and technically has the smoothest surface in the Solar System, it's far from featureless. Its frozen crust features enormous regions of broken " chaos terrain" and is covered in long, crisscrossing fractures filled with reddish-brown material ( which may be a form of sea salt), as well as crumpled, mountain-like ridges that appear curiously fresh.These ridges are thought to be a result of a form of tectonics, except not with plates of rock like on Earth but rather shifting slabs of frozen water. But where the energy needed to drive that process is coming from—and what happens to all the frictional heat created during it—isn't well known."People have been using simple mechanical models to describe the ice," said geophysicist Christine McCarthy, Lamont Assistant Research Professor at Columbia University who led the research while a graduate student at Brown University. "They weren't getting the kinds of heat fluxes that would create these tectonics. So we ran some experiments to try to understand this process better."By mechanically subjecting ice samples to various forms of pressure and stress, similar to the conditions that would be found on Europa as it orbits Jupiter, the researchers found that most of the heat is generated within deformities in the ice, rather than between the individual grains as was previously thought. This difference means there's likely a lot more heat moving through Europa's ice layers, which would affect both its behavior and its thickness."Those physics are first order in understanding the thickness of Europa's shell," said Reid Cooper, Earth science professor and McCarthy's research partner at Brown. "In turn, the thickness of the shell relative to the bulk chemistry of the moon is important in understanding the chemistry of that ocean. And if you're looking for life, then the chemistry of the ocean is a big deal."When it comes to Europa's icy crust there have traditionally been two camps of thought: the thin-icers and the thick-icers. Thin-icers estimate the moon's crust to be at most only a few kilometers thick—possibly coming very close to the surface in places, if not breaking through entirely—while those in the thick-ice camp think it could be tens of times thicker. While there are data to support both hypotheses, it remains to be seen which these new findings will best support.Luckily we won't have to wait terribly long to find out how thick the moon's icy crust really is. A recently-approved NASA mission will launch to Europa in the 2020s to explore its surface, interior composition, and potential habitability. The mission may (i.e., should) also include a lander, although of what fashion has yet to be determined. But when the data from that mission do finally come in, many of our long-standing questions about this mystifying icy world will finally be answered.The team's research is published in the June 1 issue of Earth and Planetary Science Letters. Source: PhysOrg.com The post Icy Hot: Europa’s Frozen Crust Could Be Warmer Than We Thought appeared first on Universe Today.
ExoMars Takes First Hi-Res Image With The Lens Cap On 
It doesn't exactly qualify as eye candy, but the first image from the ESA-Roscosmos ExoMars spacecraft is beautiful to behold in its own way. For most of us, a picture like this would mean something went horribly wrong with our camera. But as the first image from the spacecraft, it tells us that the camera and its pointing system are functioning properly.ExoMars is a joint project between the European Space Agency and Roscosmos, the Russian Federal Space Agency. It's an ambitious project, and consists of 2 separate launches. On March 14, 2016, the first launch took place, consisting of the Trace Gas Orbiter (TGO) and the stationary test lander called Schiaparelli, which will be delivered by the Martian surface by the TGO.TGO will investigate methane sources on Mars, and act as a communications satellite for the lander. The test lander is trying out new landing technologies, which will help with the second launch, in 2020, when a mobile rover will be launched and landed on the Martian surface.So far, all systems are go on the ExoMars craft during its voyage. "All systems have been activated and checked out, including power, communications, startrackers, guidance and navigation, all payloads and Schiaparelli, while the flight control team have become more comfortable operating this new and sophisticated spacecraft," says Peter Schmitz, ESA's Spacecraft Operations Manager.[embed]https://www.youtube.com/watch?v=kfWmn9lDgSw[/embed]Three days prior to reaching Mars, the Schiaparelli lander will separate from the TGO and begin its descent to the Martian surface. Though Schiaparelli is mostly designed to gather information about its descent and landing, it still will do some science. It has a small payload of instrument which will function for 2-8 days on the surface, studying the environment and returning the results to Earth.The TGO will perform its own set of maneuvers, inserting itself into an elliptical orbit around Mars and then spending a year aero-braking in the Martian atmosphere. After that, the TGO will settle into a circular orbit about 400 km above the surface of Mars.[embed]https://www.youtube.com/watch?v=7oK8R6D9yGM[/embed]The TGO is hunting for methane, which is a chemical signature for life. It will also be studying the surface features of Mars.[embed]https://www.youtube.com/watch?v=iUuJqXaCOWw[/embed] The post ExoMars Takes First Hi-Res Image With The Lens Cap On appeared first on Universe Today.
A Super-Fast Star System Shrugs Its Shoulders At Physics 
Astronomers have found a pair of stellar oddballs out in the edges of our galaxy. The stars in question are a binary pair, and the two companions are moving much faster than anything should be in that part of the galaxy. The discovery was reported in a paper on April 11, 2016, in the Astrophysical Journal Letters.The binary system is called PB3877, and at 18,000 light years away from us, it's not exactly in our neighborhood. It's out past the Scutum-Centaurus Arm, past the Perseus Arm, and even the Outer Arm, in an area called the galactic halo. This binary star also has the high metallicity of younger stars, rather than the low metallicity of the older stars that populate the outer reaches. So PB3877 is a puzzle, that's for sure.PB3877 is what's called a Hyper-Velocity Star (HVS), or rogue star, and though astronomers have found other HVS's, more than 20 of them in fact, this is the first binary one found. The pair consists of a hot sub-dwarf primary star that's over five times hotter than the Sun, and a cooler companion star that's about 1,000 degrees cooler than the Sun.Hyper-Velocity stars are fast, and can reach speeds of up to 1,198 km. per second, (2.7 million miles per hour,) maybe faster. At that speed, they could cross the distance from the Earth to the Moon in about 5 minutes. But what's puzzling about this binary star is not just its speed, and its binary nature, but its location.Hyper-Velocity stars themselves are rare, but PB3877 is even more rare for its location. Typically, hyper velocity stars need to be near enough to the massive black hole at the center of a galaxy to reach their incredible speeds. A star can be drawn toward the black hole, accelerated by the unrelenting pull of the hole, then sling-shotted on its way out of the galaxy. This is the same action that spacecraft can use when they gain a gravity assist by travelling close to a planet.This video shows how stars can accelerate when their orbit takes them close to the super-massive black holes at the center of the Milky Way.[embed]https://www.youtube.com/watch?v=duoHtJpo4GY[/embed]But the trajectory of PB3877 shows astronomers that it could not have originated near the center of the galaxy. And if it had been ejected by a close encounter with the black hole, how could it have survived with its binary nature intact? Surely the massive pull of the black hole would have destroyed the binary relationship between the two stars in PB3877. Something else has accelerated it to such a high speed, and astronomers want to know what, exactly, did that, and how it kept its binary nature.Barring a close encounter with the super-massive black hole at the center of the Milky Way, there are a couple other ways that PB3877 could have been accelerated to such a high velocity.One such way is a stellar interaction or collision. If two stars were travelling at the right vectors, a collision between them could impart energy to one of them and propel it to hyper-velocity. Think of two pool balls on a pool table.Another possibility is a supernova explosion. It's possible for one of the stars in a binary pair to go supernova, and eject it's companion at hyper-velocity speeds. But in these cases, either stellar collision or supernova, things would have to work out just right. And neither possibility explains how a wide-binary system like this could stay intact.Fraser Cain sheds more light on Hyper-Velocity Stars, or Rogue Stars, in this video.[embed]https://www.youtube.com/watch?v=JCj_EsoM6eM[/embed]There is another possibility, and it involves Dark Matter. Dark Matter seems to lurk on the edge of any discussion around something unexplained, and this is a case in point. The researchers think that there could be a massive cocoon or halo of Dark Matter around the binary pair, which is keeping their binary relationship intact.As for where the binary star PB3788 came from, as they say in the conclusion of their paper, "We conclude that the binary either formed in the halo or was accreted from the tidal debris of a dwarf galaxy by the Milky Way." And though the source of this star's formation is an intriguing question, and researchers plan follow up study to verify the supernova ejection possibility, its possible relationship with Dark Matter is also intriguing. The post A Super-Fast Star System Shrugs Its Shoulders At Physics appeared first on Universe Today.
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