New Technique Allows Analysis of Clouds Around Exoplanets
Posted: 04 Mar 2015 03:44 AM PST
Meteorologists sometimes struggle to accurately predict the weather here on Earth, but now we can find out how cloudy it is on planets outside our solar system, thanks to researchers at MIT. In a paper to be published in the Astrophysical Journal, researchers in the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) at MIT describe a technique that analyzes data from NASA’s Kepler space observatory to determine the types of clouds on planets that orbit other stars, known as exoplanets. The team, led by Kerri Cahoy, an assistant professor of aeronautics and astronautics at MIT, has already used the method to determine the properties of clouds on the exoplanet Kepler-7b. The planet is known as a “hot Jupiter,” as temperatures in its atmosphere hover at around 1,700 kelvins.
NASA’s Kepler spacecraft was designed to search for Earth-like planets orbiting other stars. It was pointed at a fixed patch of space, constantly monitoring the brightness of 145,000 stars. An orbiting exoplanet crossing in front of one of these stars causes a temporary dimming of this brightness, allowing researchers to detect its presence. Researchers have previously shown that by studying the variations in the amount of light coming from these star systems as a planet transits, or crosses in front or behind them, they can detect the presence of clouds in that planet’s atmosphere. That is because particles within the clouds will scatter different wavelengths of light. Modeling cloud formation To find out if this data could be used to determine the composition of these clouds, the MIT researchers studied the light signal from Kepler-7b. They used models of the temperature and pressure of the planet’s atmosphere to determine how different types of clouds would form within it, says lead author Matthew Webber, a graduate student in Cahoy’s group at MIT. “We then used those cloud models to determine how light would reflect off the atmosphere of the planet [for each type of cloud], and tried to match these possibilities to the actual observations from the Kepler mission itself,” Webber says. “So we ran a large set of models, to see which models fit best statistically to the observations.” By working backward in this way, they were able to match the Kepler spacecraft data to a type of cloud made out of vaporized silicates and magnesium. The extremely high temperatures in the Kepler-7b atmosphere mean that some minerals that commonly exist as rocks on Earth’s surface instead exist as vapors high up in the planet’s atmosphere. These mineral vapors form small cloud particles as they cool and condense. Kepler-7b is a tidally locked planet, meaning it always shows the same face to its star — just as the moon does to Earth. As a result, around half of the planet’s day side — that which constantly faces the star — is covered by these magnesium silicate clouds, the team found. “We are really doing nothing more complicated than putting a telescope into space and staring at a star with a camera,” Cahoy says. “Then we can use what we know about the universe, in terms of temperatures and pressures, how things mix, how they stratify in an atmosphere, to try to figure out what mix of things would be causing the observations that we’re seeing from these very basic instruments,” she says. A clue on exoplanet atmospheres Understanding the properties of the clouds on Kepler-7b, such as their mineral composition and average particle size, tells us a lot about the underlying physical nature of the planet’s atmosphere, says team member Nikole Lewis, a postdoc in EAPS. What’s more, the method could be used to study the properties of clouds on different types of planet, Lewis says: “It’s one of the few methods out there that can help you determine if a planet even has an atmosphere, for example.” A planet’s cloud coverage and composition also has a significant impact on how much of the energy from its star it will reflect, which in turn affects its climate and ultimately its habitability, Lewis says. “So right now we are looking at these big gas-giant planets because they give us a stronger signal,” she says. “But the same methodology could be applied to smaller planets, to help us determine if a planet is habitable or not.” The researchers hope to use the method to analyze data from NASA’s follow-up to the Kepler mission, known as K2, which began studying different patches of space last June. They also hope to use it on data from MIT’s planned Transiting Exoplanet Survey Satellite (TESS) mission, says Cahoy. “TESS is the follow-up to Kepler, led by principal investigator George Ricker, a senior research scientist in the MIT Kavli Institute for Astrophysics and Space Research. It will essentially be taking similar measurements to Kepler, but of different types of stars,” Cahoy says. “Kepler was tasked with staring at one group of stars, but there are a lot of stars, and TESS is going to be sampling the brightest stars across the whole sky,” she says. This paper is the first to take circulation models including clouds and compare them with the observed distribution of clouds on Kepler-7b, says Heather Knutson, an assistant professor of planetary science at Caltech who was not involved in the research. “Their models indicate that the clouds on this planet are most likely made from liquid rock,” Knutson says. “This may sound exotic, but this planet is a roasting hot gas-giant planet orbiting very close to its host star, and we should expect that it might look quite different than our own Jupiter.” Credit: mit.edu  | ||
|
Posted: 04 Mar 2015 03:37 AM PST
China's first lunar rover Yutu (the Jade Rabbit) is still working but cannot move, a scientist with the lunar probe mission told Xinhua. The rover, named after the pet of a Chinese goddess who flew to the moon, was launched in late 2013, but its control mechanism failed on its second lunar day before becoming dormant in January 2014. Yutu, the national pride of the world's third country to soft-land on the moon, was re-awakened, but problems remained.
Ye Peijian, chief scientist of China's Chang'e-3 program, said that the resilient rover had survived longer than its design life of three months. "For the time being, it can be re-awakened but cannot move," said the scientist, who is also a member of the National Committee of the Chinese People's Political Consultative Conference (CPPCC), China's top political advisory body. Experts said earlier that Yutu might have been damaged by a rock. Repairing the moon rover could be very difficult with it being 380,000 kilometers from earth and its voltage has dropped after repetitive contraction and expansion due to the 300 degrees centigrade temperature difference between day and night on the moon.
Credit: xinhuanet.com
 | ||
|
Posted: 03 Mar 2015 03:01 PM PST
![NASA Administrator Charles Bolden provides opening remarks for the "NACA [National Advisory Committee for Aeronautics] Centenary: A Symposium on 100 Years of Aerospace Research and Development" on March 3, 2015 at the National Air and Space Museum in Washington, DC. Congress established NACA on March 3, 1915 to address and find solutions to problems with flight. In 1958, the NACA staff, research facilities, and know-how were transitioned to the new NASA. Photo Credit: (NASA/Aubrey Gemignani)](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2d6CUqrMkxPCv3H508ebd3gQZQx9Ddk89V4Xky_OJkuBQCF-NEZyE3u2PKzIwb3OYPVLmAL-vrb_QXFb7BdCOHj5Ys5LMG5n5AssbtYcCzNEaHTYlrnyd_b9geao6XB9g6H11qhlpRdSf/s1600/16083517304_3fa43e90eb_k.jpg "NASA Administrator Charles Bolden provides opening remarks for the \"NACA [National Advisory Committee for Aeronautics] Centenary: A Symposium on 100 Years of Aerospace Research and Development\" on March 3, 2015 at the National Air and Space Museum in Washington, DC. Congress established NACA on March 3, 1915 to address and find solutions to problems with flight. In 1958, the NACA staff, research facilities, and know-how were transitioned to the new NASA. Photo Credit: (NASA/Aubrey Gemignani)")
NASA celebrates today 100 years since the founding of its predecessor - the National Advisory Committee for Aeronautics (NACA). With a small budget and no paid staff, the NACA began developing the capabilities our nation needed to gain leadership in aeronautics. Throughout and beyond World War II, the NACA developed or helped develop many aeronautical breakthroughs that are still used today. In 1958, the NACA's staff, research facilities and know-how were transitioned to the new NASA. "Today marks a special anniversary for the NASA family. It was 100 years ago, on March 3, 1915, when Congress created the National Advisory Committee for Aeronautics (NACA), the organization from which NASA was created in 1958," NASA Administrator Charles Bolden said in a statement. "Now, as we celebrate our past achievements in aviation, our resolve is renewed to continue this heritage of excellence in aeronautical research with a strategic vision that will transform aviation in areas such as autonomy, commercial supersonic flight and transition to low carbon propulsion."
When the nation's focus began turning to space during the 1950s, it was decided that the NACA's 7,500 employees and $300 million in facilities would transition on October 1, 1958, to a new agency. Some of the NACA's brightest minds became leaders of the space effort and directors of NASA research centers. One former NACA employee put the first footprints on the moon.
Engineers from the National Advisory Committee for Aeronautics (NACA), who joined NASA after its creation, tested, developed, and recommended one of the most vital technologies that the United States needed in order to successfully launch the Saturn rockets in the 1960s. These engineers had become experts in the field of high-energy propellants, particularly liquid hydrogen, and believed it should be used to power the upper stages of the Saturn rocket.
NASA is celebrating the 100th anniversary of NACA, with several events highlighting the historic committee’s contribution to the nation’s space program and aeronautics research.
This observance begins today with the NACA Centenary: A Symposium on 100 Years of Aerospace Research and Development, an event hosted by NASA and the National Air and Space Museum in Washington.
"Just as the NACA did in 1915, NASA today finds solutions to challenges facing the aerospace community that help the nation reach for new heights and reveal the unknown for the benefit of humankind. I’m proud of our heritage and the innovative work NASA continues to do in Aeronautics," Bolden said.
Credit: NASA
 | ||
|
Posted: 03 Mar 2015 02:21 PM PST
Plans for Britain to be home of Europe’s first spaceport moved a step closer today. Publishing the outcome of a 3 month consultation with a range of interested parties, the government confirmed widespread support for its plans. This paves the way towards making commercial spaceflight operations in the UK a reality. "Launching satellites and operating commercial space flights from our shores was once only confined to the depths of science fiction, but with the results of this consultation we are one step closer to making this a very real ability in the near future," said UK's Business Secretary Vince Cable.
The Civil Aviation Authority (CAA) shortlisted a number of possible locations for the spaceport in July 2014 and this has today been updated. The shortlisted sites are now Campbeltown, Glasgow Prestwick and Stornoway in Scotland, as well as Newquay in England and Llanbedr in Wales. RAF Leuchars was also confirmed as a potential temporary facility.
The government has ruled out 2 airfields at RAF Lossiemouth and Kinloss Barracks for operational reasons, given their vital role in Defence. Other locations can still be submitted if operators believe they can fulfil the requirements.
"I want Britain to lead the way in commercial spaceflight. Establishing a spaceport will ensure we are at the forefront of this exciting new technology," said Aviation minister Robert Goodwill. "Today’s consultation response marks another step forward in our work to support this emerging industry, which will create jobs and drive economic growth."
Work to establish the feasibility of a UK spaceport began in 2012, when the Department for Transport and UK Space Agency asked the CAA to review the operational environment and regulations to allow spaceplanes to operate.
Last year, the government launched its space innovation and growth strategy 2014 to 2030, which set out the economic advantages of the UK becoming a European focal point for the pioneers of commercial spaceflights and scientific research.
The next step is for the DfT to develop a detailed technical specification of spaceport requirements, prior to inviting proposals. This is due to be published later this year.
Credit: gov.uk
 | ||
|
Posted: 03 Mar 2015 01:26 PM PST
Like the lost little puppy that wanders too far from home, astronomers have found an unusually small and distant group of stars that seems oddly out of place. The cluster, made of only a handful of stars, is located far away, in the Milky Way’s “suburbs.” It is located where astronomers have never spotted such a small cluster of stars before. The new star cluster was discovered by Dongwon Kim, a PhD student at the Australian National University (ANU), together with a team of astronomers (Helmut Jerjen, Antonino Milone, Dougal Mackey, and Gary Da Costa) who are conducting the Stromlo Milky Way Satellite Survey at ANU.
“This cluster is faint, very faint, and truly in the suburbs of our Milky Way,” said Kim. “In fact, this group of stars is about ten times more distant than the average globular star cluster in the halo of our galaxy -- it's a lost puppy,” Mackey adds. Globular clusters are spherical cities of stars that form a vast, extended halo around the core of our galaxy, the brightest of which are easily seen in amateur telescopes or even binoculars. However, this new discovery required one of the world’s largest telescopes to confirm, “it’s definitely a diminutive oddball,” says Milone.
The oddly small, far-flung, cluster was discovered using the Dark Energy Camera (DECam) on the 4-meter Blanco Telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile. “This discovery sheds new light on the formation and evolution of the Milky Way,” said Daniel Evans, National Science Foundation program director for Gemini Observatory. “It's great to see so many telescopes come together to produce this result, not the least being Gemini Observatory with its incredible light-gathering power.”
The team’s first evidence of the unusually remote star cluster came when they ran detection algorithms on a 500 square-degree imaging data field obtained with DECam. “Such objects are too faint and optically elusive to be seen by eye. The cluster stars are sprinkled so thinly over the image, you look right through them without noticing (see image on electronic release, URL above). They are hiding in the sea of stars from the Milky Way. Sophisticated computer programs are our tools to find them,” said Jerjen.
Because it is so faint, ultra-deep follow-up observations using the Gemini Multi-Object Spectrograph (in imaging mode) confirmed that the new globular cluster is among the faintest Milky Way globular clusters ever found. Seven out of 150 known Milky Way globular clusters are comparably faint but none are located as far out toward the edge of the Milky Way. This new globular cluster has 10-20 times fewer stars than any of the other outer halo globular clusters. Also, its star density is less than half of that of other Milky Way globular clusters in the same luminosity (brightness) range.
The new star cluster, named Kim 2, also shows evidence of significant mass loss over its history. Computer simulations predict that, as a consequence of their evolution over many billions of years, including the slow loss of member stars due to the gravitational pull of the Milky Way, star clusters ought to be arranged such that their more massive stars are concentrated toward their centers. “This ‘mass segregation’ has been difficult to observe, particularly in low mass clusters, but the excellent Gemini data reveal that Kim 2 appears to be mass segregated and has therefore likely lost much of its original mass,” said Da Costa. The finding suggests that a substantial number of low-luminosity globular clusters must have existed in the halo when the Milky Way was younger, but most of them might have evaporated due to internal dynamical processes.
The observed properties of the new star cluster also raise the question about how such a low luminosity system could have survived until today. One possible scenario is that Kim 2 is not actually a genuine member of the Milky Way globular cluster family, but a star cluster originally located in a satellite dwarf galaxy and was accreted into the Milky Way’s halo. This picture is also supported by the fact that the stars in Kim 2 appear to be more chemically enriched with heavier elements than the other outer halo globular clusters and are young relative to the oldest globular clusters in the Milky Way. As a consequence of spending much of its life in a dwarf galaxy Kim 2 could have largely escaped the destructive influence of tidal forces, thus helping it to survive until the present epoch.
There are many Milky Way globular clusters formerly and currently associated with satellite dwarf galaxies. It is possible that a significant fraction of the ancient satellite dwarf galaxies were completely disrupted by the tidal field of the Milky Way while the high density of the globular clusters allowed them to survive in our galaxy’s halo. Indeed, Kim 2 is found close to the vast polar structure of Milky Way satellite galaxies, a disc-like region surrounding the Milky Way where satellite galaxies and young halo clusters preferentially congregate. A similar distribution of satellite galaxies is also found in the neighbouring Andromeda Galaxy.
A large fraction of the Milky Way’s halo is thought to be populated with optically elusive satellite galaxies and star clusters. New discoveries of satellite galaxies and globular clusters will therefore provide valuable information about the formation and the structure of the Milky Way. Previous surveys like the Sloan Digital Sky Survey have contributed to many new discoveries in the northern sky. However, most of the southern sky still remains unexplored to date. The detection of Kim 2 suggests that there are a substantial number of interesting astronomical objects waiting to be discovered in the southern hemisphere and the Stromlo Milky Way Satellite Survey team plans to continue searching for them.
The team's paper, accepted for publication in the Astrophysical Journal, is available as a preprint athttp://arxiv.org/abs/1502.
Credit: gemini.edu
 | ||
|
Posted: 03 Mar 2015 01:06 PM PST
As the sun skims through the galaxy, it emits charged particles in a stream of plasma called the solar wind. The solar wind, in turn, creates a bubble known called the heliosphere that extends far beyond the planets of the solar system. For decades, scientists have visualized the heliosphere as shaped like a comet, with a very long tail extending some 464 billion miles, which is thousands of times as far as the distance from Earth to the sun. New NASA-funded research now suggests that the heliosphere is actually dominated by two giant jets of material shooting backwards over the north and south poles of the sun, which are confined by the interaction of the sun’s magnetic field with the interstellar magnetic field. These curve around in two—relatively short – tails toward the back. The end result is a heliosphere without that long tail; a heliosphere that looks a lot more like a crescent moon than a comet. What's more, the two jets are similar to other astrophysical jets seen in space, so studying them locally could open doors to understanding such jets throughout the universe. The research is described in a paper in Astrophysical Journal Letters, which appeared online on Feb. 19, 2015.
"Everyone's assumption has been that the shape of the heliosphere was molded by the flow of interstellar material passing around it," said Merav Opher, an astronomer at Boston University, who is lead author on the paper. "Scientists thought the solar wind flowing down the tail could easily pull the magnetic fields in the heliosphere along as it flowed by, creating this long tail. But it turns out the magnetic fields are strong enough to resist that pull – so instead they squeeze the solar wind and create these two jets."
Opher and her colleagues found the jets and determined the new shape when they adjusted simulations of the heliosphere based on observations collected from NASA's Voyager 1 spacecraft, which recently moved outside of the heliosphere into interstellar space. As the first man-made object outside of our solar system, Voyager provided our only glimpse so far of the interstellar medium and it provided one giant surprise: The magnetic fields out there were aligned pretty much the same as the ones in here, though it had long been expected they would be oriented in a different direction.
Opher -- along with space scientist Jim Drake at the University of Maryland in College Park who is a co-author on the paper – had previously created models based on computer code developed by space physicists at the University of Michigan of the heliosphere. Their previous work focused on the nose of the heliosphere, trying to understand the physics there as we hurtle through space. To see if they could replicate the unexpected Voyager results, the team created a higher resolution simulation.
The new simulation described a heliosphere unlike one considered before.
“The Voyagers had a flashlight in the kitchen, and nobody was looking in the attic,” she remarks. “We noticed, while studying the draping of the galaxy’s magnetic field around the nose, that the heliosphere was much shorter than we anticipated."
Instead of being dominated solely by the flow of the interstellar material to create a long tail, the shape of the heliosphere is also affected by the solar wind jets emanating from the sun, said Drake.
"If there were no interstellar flow, then the magnetic fields around the sun would shape the solar wind into two jets pointing straight north and south," said Drake. "The magnetic fields contract around these jets, shooting the solar wind out like squishing a tube of toothpaste."
In the presence of the interstellar flow, these jets are bowed backwards, creating a crescent shape, as seen from the side of the sun. The jets erode in the presence of the strong interstellar flow, leading to two attenuated, short tails. This leads to a much shorter heliosphere of only about 250 times the distance between Earth and the sun, or about 23 billion miles.
"Not only is the heliosphere's shape different from what people thought," said Drake. "But the mechanism for these jets is the same as in many astrophysical systems. Astrophysical jets elsewhere produce energetic particles, but they are remote and hard to diagnose. Our jets are nearby so we might be able to figure out how they produce the energetic particles measured in the heliosphere."
To support their heliosphere model, the scientists turned to additional observations of the tail. Both NASA's Cassini and Interstellar Boundary Explorer, or IBEX, have gathered information about the tail end of the heliosphere by looking at what's called energetic neutral atoms, or ENAs. ENAs are created by energetic particle collisions in space and conveniently travel in straight lines, unlike many other particles in space. Observing ENAs traveling in from a certain area, therefore, can be used to map that region.
"Cassini data showed a similar amount of ENAs from the tail and the nose," said Opher. "Suggesting that the size of both sides was similar, which means a short tail."
An IBEX paper from 2013 also described as a two-lobed shape down the tail. Opher and Drake suggest that the lobes observed might actually have been the two jets with interstellar, non-heliospheric material in between. The paper on the IBEX results, however, interpreted the heliosphere as having a long tail.
With such previous results, Opher expects the new model to be controversial. “This is going to be heavily, heavily debated,” she said, pointing out that many scientists work from the traditional comet-shaped model of the heliosphere. But, said Opher, the out-of-the-box results coming from spacecraft observations demand a similarly unconventional explanation.
In the meantime, these newly postulated jets look like baby versions of the super-powered jets that exist around exotic objects like black holes and pulsars. They are also seen around proto-stars just being born. Being able to study these jets in our own backyard provides a homegrown laboratory in which to study a structure that is seen everywhere in the universe.
“If we’re right about all of this, it gives us a local test bed for exploring some very important physics,” said Drake.
Credit: NASA
 | ||
|
Posted: 03 Mar 2015 12:01 PM PST
Senator Barbara A. Mikulski (D-Md.), one of the most powerful figures in space policy in Congress, announced Monday she has decided not to run for re-election. Mikulski, who will complete her 5th term in office in January, 2017, says she wants to focus for the next two years on working for her constituents and for the nation. "I’m here to announce I won’t be seeking a 6th term as a United States Senator for Maryland," she said at a press conference in Baltimore. “To the people of Maryland -- I thank you. You’ve honored me with your confidence and trust." NASA Administrator Charles Bolden lauded Mikulski for championing America’s space program. “Her steadfast support for the Goddard Space Flight Center and its extraordinary science, including the Hubble Space Telescope, the James Webb Space Telescope and dozens of missions that are expanding our journey of discovery, will give current and future generations of Americans a better understanding of our world and our universe. Her candor, passion and vision will be greatly missed," Bolden said in a statement.
Mikulski said she decided not to run in order to devote the next two years solely to working in the Senate, rather than campaigning and raising money.
Mikulski currently serves as the ranking member of the Senate Appropriations Committee and its commerce, justice, and science (CJS) subcommittee, whose oversight includes NASA. Mikulski has served on the committee since she was first elected to the Senate in 1986.
She has used that position to become an influential figure in space policy, particularly in programs involving the Goddard Space Flight Center and the Space Telescope Science Institute, both located in Maryland. She has also supported NASA’s Wallops Flight Facility, which is located in Virginia just south of the Maryland border and managed by Goddard.
She was also instrumental in helping the International Space Station off the ground despite programmatic difficulties and cost overruns that fueled deep skepticism about the program’s value in many corners of Capitol Hill.
Similarly, Mikulski has been a major supporter of the James Webb Space Telescope, which is still in development, seeking full funding for the program while pressuring NASA to improve its management after it suffered major schedule delays and cost overruns.
“Senator Mikulski has been a tireless champion for NASA, and has helped pave the way for future exploration and our journey to Mars," Bolden said. “She has inspired future generations to study science, technology, education and mathematics and helped ensure America's continued leadership in space. We salute her service to the American people.”
 | ||
|
Posted: 03 Mar 2015 11:17 AM PST
The U.S. Joint Space Operations Center is tracking a debris field of 43 objects after a weather satellite launched in 1995 apparently exploded. The incident occurred after National Oceanic and Atmospheric Administration operators detected a thermal spike in the satellite on Feb. 3, Air Force Space Command officials say. A decision was made to "render the vehicle safe [i.e., shut down all non-essential systems] after [Defense Meteorological Satellite Program Flight 13 (DMSP-13)] operators discovered a sudden spike in temperature in the power subsystem ... followed by an unrecoverable loss of attitude control," according to a statement from Air Force Space Command. The satellite reached its end of life on Feb. 3 at 4:39 a.m. EST. Space News was first to report the event.
DMSP now consists of six satellites orbiting Earth at an altitude of about 500 miles. The constellation tracks existing weather systems and developing weather patterns and can relay data in real time for Army, Navy, Air Force and Marine forces. The system also can be used to create 3D cloud analyses and help with high-frequency communications, over-the-horizon radar and spacecraft drag and reentry tasks, according to the Air Force.
DMSP is the longest-running production satellite program in history, according Lockheed Martin, which along with Northrop Grumman is the prime contractor. Initiated in 1962, it was highly classified until 1973. The exploded satellite, known as DMSP Flight 13, was launched in 1995. The most recent addition to the constellation, DMSP-F19, was launched in April 2014.
The program is managed by the Air Force’s Space and Missile Systems Center at Los Angeles Air Force Base, with command and control provided by a joint-operational team at the National Oceanic and Atmospheric Administration.
Credit: aviationweek.com, defe
 | ||
|
Posted: 03 Mar 2015 10:44 AM PST
Over 1,000 people joined in at the Shire of Kalamunda's (Australia) 'World's Largest Astronomy Lesson' on the weekend, helping to break a Guinness World Record. The conditions were perfect, with not a cloud in sight when 1,100 participants all brought their binoculars and telescopes to the Maida Vale Nature Reserve on Saturday to learn more about the night sky. The previous world record was 834 participants, held by Eagle Cultural and Educational Enterprises and Youth Cultural Creative and Philanthropy Consortium in Chinese Taipei in June 2014.
Rick guided the participants through a journey of the skies, focusing on the life cycle of a star. Starting with the stellar nursery in the Great Orion Nebula, Rick then had particpants look towards the Southern Cross to find the Wishing Well open cluster of stars. Then it was on to a Sun-like star (Beta Hydri) and finally talking about the formation of planets whilst viewing Jupiter and the Moon.
A resounding cheer rose from the crowd as the siren sounded to mark the end of the record attempt, and the breaking of the world record.
The attempt in Perth will now be verified by the Guinness World Records organisation after the submission of volunteer reports and documentation. ICRAR was a proud partner of the Shire's event, together with the Perth Observatory Volunteer Group.
Credit: icrar.org
 | ||
|
Posted: 03 Mar 2015 08:51 AM PST
Mercury's surface is riven by large tectonic structures that formed when the planet's interior cooled and contracted. One of the most notable such structures is Enterprise Rupes, a lobate scarp system 822 km (510 mi.) in length. Enterprise Rupes cross-cuts the majestic Rembrandt impact basin, some 716 km (445 mi.) across. Rembrandt itself hosts numerous examples where lobate scarps cross smaller craters, such as that shown here.
The scarp in this scene lies close to the perimeter of Rembrandt and parallels the basin's outline, before crossing Enterprise Rupes itself farther to the north.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. In the mission's more than three years of orbital operations, MESSENGER has acquired over 250,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015.
Credit: messenger.jhuapl.edu
|
2015년 3월 4일 수요일
Astro Watch
피드 구독하기:
댓글 (Atom)
댓글 없음:
댓글 쓰기