The following excerpt is from the NASA website:
"NASA’s Lunar Reconnaissance Orbiter science team released the highest resolution near-global topographic map of the moon ever created. This new topographic map shows the surface shape and features over nearly the entire moon with a pixel scale close to 328 feet.
Although the moon is Earth's closest neighbor, knowledge of its morphology is still limited. Due to the limitations of previous missions, a global map of the moon’s topography at high resolution has not existed until now. With LRO's Wide Angle Camera and the Lunar Orbiter Laser Altimeter instrument, scientists can now accurately portray the shape of the entire moon at high resolution."
The International Space Station. Credit: NASA
Saturday, November 26, 2011
Friday, November 18, 2011
COLLAPSE OF MASSIVE STAR CREATES A STELLAR-MASS BLACK HOLE
The following excerpt is from the NASA website:
"On the left, an optical image from the Digitized Sky Survey shows Cygnus X-1, outlined in a red box. Cygnus X-1 is located near large active regions of star formation in the Milky Way, as seen in this image that spans some 700 light years across. An artist's illustration on the right depicts what astronomers think is happening within the Cygnus X-1 system. Cygnus X-1 is a so-called stellar-mass black hole, a class of black holes that comes from the collapse of a massive star. The black hole pulls material from a massive, blue companion star toward it. This material forms a disk (shown in red and orange) that rotates around the black hole before falling into it or being redirected away from the black hole in the form of powerful jets.
A trio of papers with data from radio, optical and X-ray telescopes, including NASA's Chandra X-ray Observatory, has revealed new details about the birth of this famous black hole that took place millions of years ago. Using X-ray data from Chandra, the Rossi X-ray Timing Explorer, and the Advanced Satellite for Cosmology and Astrophysics, scientists were able to determine the spin of Cygnus X-1 with unprecedented accuracy, showing that the black hole is spinning at very close to its maximum rate. Its event horizon -- the point of no return for material falling towards a black hole -- is spinning around more than 800 times a second.
Using optical observations of the companion star and its motion around its unseen companion, the team also made the most precise determination ever for the mass of Cygnus X-1, of 14.8 times the mass of the Sun. It was likely to have been almost this massive at birth, because of lack of time for it to grow appreciably."
"On the left, an optical image from the Digitized Sky Survey shows Cygnus X-1, outlined in a red box. Cygnus X-1 is located near large active regions of star formation in the Milky Way, as seen in this image that spans some 700 light years across. An artist's illustration on the right depicts what astronomers think is happening within the Cygnus X-1 system. Cygnus X-1 is a so-called stellar-mass black hole, a class of black holes that comes from the collapse of a massive star. The black hole pulls material from a massive, blue companion star toward it. This material forms a disk (shown in red and orange) that rotates around the black hole before falling into it or being redirected away from the black hole in the form of powerful jets.
A trio of papers with data from radio, optical and X-ray telescopes, including NASA's Chandra X-ray Observatory, has revealed new details about the birth of this famous black hole that took place millions of years ago. Using X-ray data from Chandra, the Rossi X-ray Timing Explorer, and the Advanced Satellite for Cosmology and Astrophysics, scientists were able to determine the spin of Cygnus X-1 with unprecedented accuracy, showing that the black hole is spinning at very close to its maximum rate. Its event horizon -- the point of no return for material falling towards a black hole -- is spinning around more than 800 times a second.
Using optical observations of the companion star and its motion around its unseen companion, the team also made the most precise determination ever for the mass of Cygnus X-1, of 14.8 times the mass of the Sun. It was likely to have been almost this massive at birth, because of lack of time for it to grow appreciably."
Tuesday, November 15, 2011
GALATIC ENCOUNTERS MAY CAUSE GROWTH OF HUGE BLACK HOLES
The following excerpt is from the NASA website:
"Astronomers have used a large survey to test a prediction that close encounters between galaxies can trigger the rapid growth of supermassive black holes. Key to this work was Chandra's unique ability to pinpoint actively growing black holes through the X-rays they generate.
The researchers looked at 562 pairs of galaxies ranging in distances from about 3 billion to 8 billion light years from Earth. They found that the galaxies in the early stages of an encounter with another were more likely than isolated, or "lonelier" galaxies to have actively growing black holes in their cores.
These two composite images show a sample of the pairs of galaxies that are undergoing close encounters in the survey. In these images, the data from NASA's Chandra X-ray Observatory are shown in purple and Hubble Space Telescope data are in gold. In both images, the point-like X-ray source near the center is generated by gas that has been heated to millions of degrees as it falls toward a supermassive black hole located in the middle of its host galaxy. The other faint X-ray emission may be caused by hot gas associated with the pair of galaxies.
The authors of the study estimate that nearly one-fifth of all moderately active black holes are found in galaxies undergoing the early stages of an interaction. This leaves open the question of what events are responsible for fueling the remaining 80% of growing black holes. Some of these may involve the late stages of mergers between two galaxies. Less violent events such as gas falling in from the halo of the galaxy, or the disruption of small satellite galaxies are also likely to play an important role.
The survey used in this research is called the Cosmic Evolution Survey (COSMOS), which covers two square degrees on the sky with observations from several major space-based observatories including Chandra and Hubble. Accurate distance information about the galaxies was also derived from optical observations with the European Southern Observatory's Very Large Telescope. The researchers compared a sample of 562 galaxies in pairs with 2726 solo galaxies to come to their conclusions.
A paper describing this work has been accepted for publication in The Astrophysical Journal. The study was led by John Silverman from the Institute for the Physics and Mathematics of the Universe (IPMU) at the University of Tokyo in Japan. There are 54 co-authors from various institutions around the world.
Credits: X-ray: NASA/CXC/IPMU/J.Silverman et al; Optical: NASA/STScI/Caltech/N.Scoville et al."
"Astronomers have used a large survey to test a prediction that close encounters between galaxies can trigger the rapid growth of supermassive black holes. Key to this work was Chandra's unique ability to pinpoint actively growing black holes through the X-rays they generate.
The researchers looked at 562 pairs of galaxies ranging in distances from about 3 billion to 8 billion light years from Earth. They found that the galaxies in the early stages of an encounter with another were more likely than isolated, or "lonelier" galaxies to have actively growing black holes in their cores.
These two composite images show a sample of the pairs of galaxies that are undergoing close encounters in the survey. In these images, the data from NASA's Chandra X-ray Observatory are shown in purple and Hubble Space Telescope data are in gold. In both images, the point-like X-ray source near the center is generated by gas that has been heated to millions of degrees as it falls toward a supermassive black hole located in the middle of its host galaxy. The other faint X-ray emission may be caused by hot gas associated with the pair of galaxies.
The authors of the study estimate that nearly one-fifth of all moderately active black holes are found in galaxies undergoing the early stages of an interaction. This leaves open the question of what events are responsible for fueling the remaining 80% of growing black holes. Some of these may involve the late stages of mergers between two galaxies. Less violent events such as gas falling in from the halo of the galaxy, or the disruption of small satellite galaxies are also likely to play an important role.
The survey used in this research is called the Cosmic Evolution Survey (COSMOS), which covers two square degrees on the sky with observations from several major space-based observatories including Chandra and Hubble. Accurate distance information about the galaxies was also derived from optical observations with the European Southern Observatory's Very Large Telescope. The researchers compared a sample of 562 galaxies in pairs with 2726 solo galaxies to come to their conclusions.
A paper describing this work has been accepted for publication in The Astrophysical Journal. The study was led by John Silverman from the Institute for the Physics and Mathematics of the Universe (IPMU) at the University of Tokyo in Japan. There are 54 co-authors from various institutions around the world.
Credits: X-ray: NASA/CXC/IPMU/J.Silverman et al; Optical: NASA/STScI/Caltech/N.Scoville et al."
Monday, November 7, 2011
DAN TANI TALKS ABOUT BEING AN ASTRONAUT
The following excerpt is from the NASA website:
In Their Own Words
Dan Tani,
Astronaut
What made you want to become an astronaut?
When I was a little boy, I was not one of those astronauts, and there are some, that wanted to be an astronaut when they were four years old or six years old. But I loved, I thought aviation was incredibly exciting and I liked model rockets. I used to fly model rockets when I was in elementary school. Just making stuff go fast and high was really exciting. Of course, if you would have asked me if I wanted to be an astronaut, I would have said absolutely, but it wasn't something I carried as a goal since childhood.
And then in college I became an engineer and learned how stuff works, how to build things and I got a job in an aerospace company and we were building satellites and satellite parts and I got to meet a few astronauts and when I met them I realized, hey, it's a job and I never even thought of being an astronaut as a job. /// And then I heard they were taking applications for that job, so I thought, who doesn't want to be an astronaut? /// So, got the application, filled it in, mailed it off and almost forgot about it. I just felt like I bought the lottery ticket, stuck it in my pocket and forgot about it. I was really surprised when they gave me a call and asked me if I wanted to interview and equally surprised when I got selected for the class of '96.
What is astronaut training like?
It's fun. We sort of go back to school. For the first two years we're called astronaut candidates, or ASCANs for short and ASCAN training is learning everything you can about NASA so we go to all the centers, we learn about what they do. It's all about learning how the space station works, when I joined it was all about learning how the space shuttle works and then it's about all the skills you're going to need as an astronaut, so some robotics skills and some spacewalking skills and some fix-it skills and some speaking skills. And so it's sort of going to school for almost two years and then when you come out of it, you're an eligible astronaut for assignment and the lucky ones get picked first and the more normal ones like us have to wait a little bit and so it was five years, I guess it was four years after I joined that I got selected for my first mission.
What was adapting to space like?
It felt pretty normal pretty quickly. When we go up on the space shuttle, we don't dock until the third day and so that means we have two full days of living in the space shuttle to kind of get used to weightlessness, to get used to brushing your teeth in weightlessness, putting on your socks, which is comically difficult to do in weightlessness and so you've sort of adapted that, doing your everyday stuff in weightlessness. Now you get into the station and it's a real benefit, there's just a lot more room. There's more to, so you're not elbowing your buddy every time you want to move around, or, again, when you put on your socks or your shoes and so in that way it's a lot easier. And then we, space station is outfitted with lots of computers to provide you some entertainment, also some communication with home so you can talk to your family virtually every day and so that feels a lot more normal. So living on the space station I thought was a very fast adaptation.
Describe the view from space?
The two great things about going into space are floating and looking out the window, and they would flip-flop in priority day to day in my mind. Looking out the window is a spectacular privilege. We're two hundred something miles above the Earth, we're going 17,000 mph, we cover most of the populated land mass because of the inclination of our orbit.
To look down at the earth and see both very familiar sights like your hometown and unfamiliar sights like the middle of Australia, which is incredibly beautiful, the colors and textures of central Australia are just spectacular, that was a motivator every day for space for me. Even out the little window, it was amazing.
So now you put the helmet on, you put the spacesuit on, you get in the airlock, you close the door behind you, you open the door out into space and now your window has become a full, 180-degree mask view. And the thing about spacewalks is we're not out there for the view, we're there to do the work and I think every spacewalker would tell you, the view is great, we think, because as far as I remember, every spacewalk was stuff right here. And so my memory of the spacewalks really is what's here and I had to force myself to have moments where I would appreciate the setting, the view and take some pictures and remember it that way. It is spectacular. It's amazing to hold onto the International Space Station, you're going 17 and a half thousand miles an hour, and hold on and just sort of look down at your feet and 200 miles under your feet, there goes the coast of California and, oops, nine minutes later, there goes New York City as you're flying over and then on your way to Europe.
What was the biggest surprise of spaceflight?
The biggest surprise to me was that when you're in space, with the weightlessness, it is, I call weightlessness 75 percent enjoyable, 75 percent unbelievably fun, 25 percent just a pain in the neck. And the pain the neck aspect is you're used to, on the ground you're used to doing things without thinking, you're used to writing something down, putting the pen down. The pen stays there, the paper stays there and you can turn around and when you turn back, the pen's there, paper's there.
Well, since everything floats in space, you have to think about absolutely everything you touch and everything that you want to touch. When you're eating, in space, you have to, generally people will eat one thing at a time because to eat your meat and your potatoes and your drink, you have to hold down, tie down, find a fixture for each item between if you're going to pick something new. Otherwise you're just juggling stuff and it'll get out of control. So generally most people will eat one thing, all, fold it up, throw that away. Open up the next thing, eat that next thing and roll it up, throw that away. Deal with one thing at a time because it's just too complex to have more than two things, one thing in each hand, at any time. And one of the pleasures of coming back to the ground was not having to think about eating, not having to think about my utensils. I could put them down and it was magic, they just stayed right there."
In Their Own Words
Dan Tani,
Astronaut
What made you want to become an astronaut?
When I was a little boy, I was not one of those astronauts, and there are some, that wanted to be an astronaut when they were four years old or six years old. But I loved, I thought aviation was incredibly exciting and I liked model rockets. I used to fly model rockets when I was in elementary school. Just making stuff go fast and high was really exciting. Of course, if you would have asked me if I wanted to be an astronaut, I would have said absolutely, but it wasn't something I carried as a goal since childhood.
And then in college I became an engineer and learned how stuff works, how to build things and I got a job in an aerospace company and we were building satellites and satellite parts and I got to meet a few astronauts and when I met them I realized, hey, it's a job and I never even thought of being an astronaut as a job. /// And then I heard they were taking applications for that job, so I thought, who doesn't want to be an astronaut? /// So, got the application, filled it in, mailed it off and almost forgot about it. I just felt like I bought the lottery ticket, stuck it in my pocket and forgot about it. I was really surprised when they gave me a call and asked me if I wanted to interview and equally surprised when I got selected for the class of '96.
What is astronaut training like?
It's fun. We sort of go back to school. For the first two years we're called astronaut candidates, or ASCANs for short and ASCAN training is learning everything you can about NASA so we go to all the centers, we learn about what they do. It's all about learning how the space station works, when I joined it was all about learning how the space shuttle works and then it's about all the skills you're going to need as an astronaut, so some robotics skills and some spacewalking skills and some fix-it skills and some speaking skills. And so it's sort of going to school for almost two years and then when you come out of it, you're an eligible astronaut for assignment and the lucky ones get picked first and the more normal ones like us have to wait a little bit and so it was five years, I guess it was four years after I joined that I got selected for my first mission.
What was adapting to space like?
It felt pretty normal pretty quickly. When we go up on the space shuttle, we don't dock until the third day and so that means we have two full days of living in the space shuttle to kind of get used to weightlessness, to get used to brushing your teeth in weightlessness, putting on your socks, which is comically difficult to do in weightlessness and so you've sort of adapted that, doing your everyday stuff in weightlessness. Now you get into the station and it's a real benefit, there's just a lot more room. There's more to, so you're not elbowing your buddy every time you want to move around, or, again, when you put on your socks or your shoes and so in that way it's a lot easier. And then we, space station is outfitted with lots of computers to provide you some entertainment, also some communication with home so you can talk to your family virtually every day and so that feels a lot more normal. So living on the space station I thought was a very fast adaptation.
Describe the view from space?
The two great things about going into space are floating and looking out the window, and they would flip-flop in priority day to day in my mind. Looking out the window is a spectacular privilege. We're two hundred something miles above the Earth, we're going 17,000 mph, we cover most of the populated land mass because of the inclination of our orbit.
To look down at the earth and see both very familiar sights like your hometown and unfamiliar sights like the middle of Australia, which is incredibly beautiful, the colors and textures of central Australia are just spectacular, that was a motivator every day for space for me. Even out the little window, it was amazing.
So now you put the helmet on, you put the spacesuit on, you get in the airlock, you close the door behind you, you open the door out into space and now your window has become a full, 180-degree mask view. And the thing about spacewalks is we're not out there for the view, we're there to do the work and I think every spacewalker would tell you, the view is great, we think, because as far as I remember, every spacewalk was stuff right here. And so my memory of the spacewalks really is what's here and I had to force myself to have moments where I would appreciate the setting, the view and take some pictures and remember it that way. It is spectacular. It's amazing to hold onto the International Space Station, you're going 17 and a half thousand miles an hour, and hold on and just sort of look down at your feet and 200 miles under your feet, there goes the coast of California and, oops, nine minutes later, there goes New York City as you're flying over and then on your way to Europe.
What was the biggest surprise of spaceflight?
The biggest surprise to me was that when you're in space, with the weightlessness, it is, I call weightlessness 75 percent enjoyable, 75 percent unbelievably fun, 25 percent just a pain in the neck. And the pain the neck aspect is you're used to, on the ground you're used to doing things without thinking, you're used to writing something down, putting the pen down. The pen stays there, the paper stays there and you can turn around and when you turn back, the pen's there, paper's there.
Well, since everything floats in space, you have to think about absolutely everything you touch and everything that you want to touch. When you're eating, in space, you have to, generally people will eat one thing at a time because to eat your meat and your potatoes and your drink, you have to hold down, tie down, find a fixture for each item between if you're going to pick something new. Otherwise you're just juggling stuff and it'll get out of control. So generally most people will eat one thing, all, fold it up, throw that away. Open up the next thing, eat that next thing and roll it up, throw that away. Deal with one thing at a time because it's just too complex to have more than two things, one thing in each hand, at any time. And one of the pleasures of coming back to the ground was not having to think about eating, not having to think about my utensils. I could put them down and it was magic, they just stayed right there."
Tuesday, November 1, 2011
NASA TO HOST A HUMAN SPACE EXPLORATION WORKSHOP IN NOVEMBER
The following excerpt is from the NASA website:
“WASHINGTON -- NASA will host a three-day Human Space Exploration Community Workshop in San Diego starting on Monday, Nov. 14. The agency will introduce the International Space Exploration Coordination Group's Global Exploration Roadmap during the event.
The workshop will frame the Global Exploration Roadmap, with overviews of NASA's plans for human spaceflight, including exploration missions to an asteroid and Mars. The goal is to review the work done developing international exploration scenarios while seeking community input on the long-term scenarios represented in the roadmap.
NASA is seeking industry and academia feedback to shape strategy, assist with investment priorities and refine international exploration scenarios for human exploration and operations through the 2020's. The agency has outlined an ambitious program moving forward that relies on private industry to assume transportation of cargo and crew to the International Space Station, while NASA focuses on deep space exploration.
The workshop is part of a continuing agency effort to engage the broader space community in appropriate forums. More events will follow as part of a series of "theme focused" opportunities for human spaceflight exploration planning and engagement.”
“WASHINGTON -- NASA will host a three-day Human Space Exploration Community Workshop in San Diego starting on Monday, Nov. 14. The agency will introduce the International Space Exploration Coordination Group's Global Exploration Roadmap during the event.
The workshop will frame the Global Exploration Roadmap, with overviews of NASA's plans for human spaceflight, including exploration missions to an asteroid and Mars. The goal is to review the work done developing international exploration scenarios while seeking community input on the long-term scenarios represented in the roadmap.
NASA is seeking industry and academia feedback to shape strategy, assist with investment priorities and refine international exploration scenarios for human exploration and operations through the 2020's. The agency has outlined an ambitious program moving forward that relies on private industry to assume transportation of cargo and crew to the International Space Station, while NASA focuses on deep space exploration.
The workshop is part of a continuing agency effort to engage the broader space community in appropriate forums. More events will follow as part of a series of "theme focused" opportunities for human spaceflight exploration planning and engagement.”
FLOWS ON THE SLOPES OF MARS
The following is from the NASA website:
This image, which combines orbital imagery with 3-D modeling, shows flows that appear in spring and summer on a slope inside Mars' Newton Crater. Sequences of observations recording the seasonal changes at this site and a few others with similar flows might be evidence of salty liquid water active on Mars today. Evidence for that possible interpretation is presented in a report by McEwen et al. in the Aug. 5, 2011, edition of Science. This image has been reprojected to show a view of a slope as it would be seen from a helicopter inside the crater, with a synthetic Mars-like sky. The source observation was made May 30, 2011, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Color has been enhanced. The season was summer at the location, 41.6 degrees south latitude, 202.3 degrees east longitude. The flow features are narrow (one-half to five yards or meters wide), relatively dark markings on steep (25 to 40 degree) slopes at several southern hemisphere locations. Repeat imaging by HiRISE shows the features appear and incrementally grow during warm seasons and fade in cold seasons. Image Credit: NASA/JPL-Caltech/Univ. of Arizona
This e-mail update was generated automatically based on your subscriptions. Some updates may belong to more than one category, resulting in duplicate notices."
This image, which combines orbital imagery with 3-D modeling, shows flows that appear in spring and summer on a slope inside Mars' Newton Crater. Sequences of observations recording the seasonal changes at this site and a few others with similar flows might be evidence of salty liquid water active on Mars today. Evidence for that possible interpretation is presented in a report by McEwen et al. in the Aug. 5, 2011, edition of Science. This image has been reprojected to show a view of a slope as it would be seen from a helicopter inside the crater, with a synthetic Mars-like sky. The source observation was made May 30, 2011, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Color has been enhanced. The season was summer at the location, 41.6 degrees south latitude, 202.3 degrees east longitude. The flow features are narrow (one-half to five yards or meters wide), relatively dark markings on steep (25 to 40 degree) slopes at several southern hemisphere locations. Repeat imaging by HiRISE shows the features appear and incrementally grow during warm seasons and fade in cold seasons. Image Credit: NASA/JPL-Caltech/Univ. of Arizona
This e-mail update was generated automatically based on your subscriptions. Some updates may belong to more than one category, resulting in duplicate notices."
Tuesday, October 25, 2011
NEEMO 15 AND WORK ON ASTEROID SURFACES
The following article excerpt is from the NASA website:
NEEMO 15 Commander Shannon Walker (NASA) and fellow aquanaut David Saint-Jacques (Canadian Space Agency) use a small telescoping boom as a means of translating across a simulated asteroid surface. Each end of the small boom can be anchored to the surface by either magnets or tethers and the astronauts can traverse the surface by alternating anchor points. Various translation techniques are being tested during this 13-day NEEMO mission.
NEEMO, which stands for NASA Extreme Environment Mission Operations, is one facet of NASA's Analog and Field Testing Missions. As NASA plans to expand human spaceflight and robotic exploration beyond low Earth orbit, astronauts are being trained to meet these challenges. Future destinations may include the moon, near Earth asteroids and Mars and its moons.
To prepare for the challenge of exploring these destinations in space, NASA conducts missions here on Earth, in remote locations that have physical similarities to extreme space environments.
NEEMO 15 Commander Shannon Walker (NASA) and fellow aquanaut David Saint-Jacques (Canadian Space Agency) use a small telescoping boom as a means of translating across a simulated asteroid surface. Each end of the small boom can be anchored to the surface by either magnets or tethers and the astronauts can traverse the surface by alternating anchor points. Various translation techniques are being tested during this 13-day NEEMO mission.
NEEMO, which stands for NASA Extreme Environment Mission Operations, is one facet of NASA's Analog and Field Testing Missions. As NASA plans to expand human spaceflight and robotic exploration beyond low Earth orbit, astronauts are being trained to meet these challenges. Future destinations may include the moon, near Earth asteroids and Mars and its moons.
To prepare for the challenge of exploring these destinations in space, NASA conducts missions here on Earth, in remote locations that have physical similarities to extreme space environments.
Friday, October 21, 2011
DISK OF WATER FOUND SURROUNDING FORMING STAR
The following excerpt is from the NASA website:
“WASHINGTON -- Using data from the Herschel Space Observatory, astronomers have detected for the first time cold water vapor enveloping a dusty disk around a young star. The findings suggest that this disk, which is poised to develop into a solar system, contains great quantities of water, suggesting that water-covered planets like Earth may be common in the universe. Herschel is a European Space Agency mission with important NASA contributions.
Scientists previously found warm water vapor in planet-forming disks close to a central star. Evidence for vast quantities of water extending out into the cooler, far reaches of disks where comets take shape had not been seen until now. The more water available in disks for icy comets to form, the greater the chances that large amounts eventually will reach new planets through impacts.
"Our observations of this cold vapor indicate enough water exists in the disk to fill thousands of Earth oceans," said astronomer Michiel Hogerheijde of Leiden Observatory in The Netherlands. Hogerheijde is the lead author of a paper describing these findings in the Oct. 21 issue of the journal Science.
The star with this water-logged disk, called TW Hydrae, is 10 million years old and located about 175 light-years away from Earth, in the constellation Hydra. The frigid watery haze detected by Hogerheijde and his team is thought to originate from ice-coated grains of dust near the disk's surface. Ultraviolet light from the star causes some water molecules to break free of this ice, creating a thin layer of gas with a light signature detected by Herschel's Heterodyne Instrument for the Far-Infrared, or HIFI.
"These are the most sensitive HIFI observations to-date," said Paul Goldsmith, NASA project scientist for the Herschel Space Observatory at the agency's Jet Propulsion Laboratory in Pasadena, Calif. "It is a testament to the instrument-builders that such weak signals can be detected."
TW Hydrae is an orange dwarf star, somewhat smaller and cooler than our yellow-white sun. The giant disk of material that encircles the star has a size nearly 200 times the distance between Earth and the sun. Over the next few million years, astronomers believe matter within the disk will collide and grow into planets, asteroids and other cosmic bodies. Dust and ice particles will assemble as comets.
As the new solar system evolves, icy comets are likely to deposit much of the water they contain on freshly created worlds through impacts, giving rise to oceans. Astronomers believe TW Hydrae and its icy disk may be representative of many other young star systems, providing new insights on how planets with abundant water could form throughout the universe.
Herschel is a European Space Agency cornerstone mission launched in 2009, carrying science instruments provided by consortia of European institutes. NASA's Herschel Project Office based at JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the U.S. astronomical community. Caltech manages JPL for NASA.”
“WASHINGTON -- Using data from the Herschel Space Observatory, astronomers have detected for the first time cold water vapor enveloping a dusty disk around a young star. The findings suggest that this disk, which is poised to develop into a solar system, contains great quantities of water, suggesting that water-covered planets like Earth may be common in the universe. Herschel is a European Space Agency mission with important NASA contributions.
Scientists previously found warm water vapor in planet-forming disks close to a central star. Evidence for vast quantities of water extending out into the cooler, far reaches of disks where comets take shape had not been seen until now. The more water available in disks for icy comets to form, the greater the chances that large amounts eventually will reach new planets through impacts.
"Our observations of this cold vapor indicate enough water exists in the disk to fill thousands of Earth oceans," said astronomer Michiel Hogerheijde of Leiden Observatory in The Netherlands. Hogerheijde is the lead author of a paper describing these findings in the Oct. 21 issue of the journal Science.
The star with this water-logged disk, called TW Hydrae, is 10 million years old and located about 175 light-years away from Earth, in the constellation Hydra. The frigid watery haze detected by Hogerheijde and his team is thought to originate from ice-coated grains of dust near the disk's surface. Ultraviolet light from the star causes some water molecules to break free of this ice, creating a thin layer of gas with a light signature detected by Herschel's Heterodyne Instrument for the Far-Infrared, or HIFI.
"These are the most sensitive HIFI observations to-date," said Paul Goldsmith, NASA project scientist for the Herschel Space Observatory at the agency's Jet Propulsion Laboratory in Pasadena, Calif. "It is a testament to the instrument-builders that such weak signals can be detected."
TW Hydrae is an orange dwarf star, somewhat smaller and cooler than our yellow-white sun. The giant disk of material that encircles the star has a size nearly 200 times the distance between Earth and the sun. Over the next few million years, astronomers believe matter within the disk will collide and grow into planets, asteroids and other cosmic bodies. Dust and ice particles will assemble as comets.
As the new solar system evolves, icy comets are likely to deposit much of the water they contain on freshly created worlds through impacts, giving rise to oceans. Astronomers believe TW Hydrae and its icy disk may be representative of many other young star systems, providing new insights on how planets with abundant water could form throughout the universe.
Herschel is a European Space Agency cornerstone mission launched in 2009, carrying science instruments provided by consortia of European institutes. NASA's Herschel Project Office based at JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the U.S. astronomical community. Caltech manages JPL for NASA.”
Friday, August 26, 2011
TWIN SATELITES WILL EXPLORE THE MOON
It's great we are going back to the moon. The moon may be the best place to build a permanent space station from which we can explore the solar system. The followig story about the new moon mission is an excerpt from the NASA website:
NASA Moon Mission In Final Preparations For September Launch
CAPE CANAVERAL, Fla. -- NASA's Gravity Recovery And Interior Laboratory (GRAIL), mission to study the moon is in final launch preparations for a scheduled Sept. 8 launch onboard a Delta II rocket from Cape Canaveral Air Force Station in Florida.
GRAIL's twin spacecraft are tasked for a nine-month mission to explore Earth's nearest neighbor in unprecedented detail. They will determine the structure of the lunar interior from crust to core and advance our understanding of the thermal evolution of the moon.
"Yesterday's final encapsulation of the spacecraft is an important mission milestone," said David Lehman, GRAIL project manager for NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Our two spacecraft are now sitting comfortably inside the payload fairing which will protect them during ascent. Next time the GRAIL twins will see the light of day they will be about 95 miles up and accelerating."
The spacecraft twins, GRAIL A and B, will fly a circuitous route to lunar orbit taking 3.5 months and covering approximately 2.6 million miles (4.2 million kilometers) for GRAIL-A, and 2.7 million miles (4.3 million kilometers) for GRAIL-B.
In lunar orbit, the spacecraft will transmit radio signals precisely defining the distance between them. Regional gravitational differences on the moon are expected to expand and contract that distance. GRAIL scientists will use these accurate measurements to define the moon's gravity field. The data will allow mission scientists to understand what goes on below the surface of our natural satellite.
"GRAIL will unlock lunar mysteries and help us understand how the moon, Earth and other rocky planets evolved as well," said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge.
GRAIL's launch period opens Sept. 8 and extends through Oct. 19. On each day, there are two separate launch opportunities separated by approximately 39 minutes. On Sept. 8, the first launch opportunity is 8:37 a.m. EDT; the second is 9:16 a.m.
JPL manages the GRAIL mission. It is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver, built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida.”
NASA Moon Mission In Final Preparations For September Launch
CAPE CANAVERAL, Fla. -- NASA's Gravity Recovery And Interior Laboratory (GRAIL), mission to study the moon is in final launch preparations for a scheduled Sept. 8 launch onboard a Delta II rocket from Cape Canaveral Air Force Station in Florida.
GRAIL's twin spacecraft are tasked for a nine-month mission to explore Earth's nearest neighbor in unprecedented detail. They will determine the structure of the lunar interior from crust to core and advance our understanding of the thermal evolution of the moon.
"Yesterday's final encapsulation of the spacecraft is an important mission milestone," said David Lehman, GRAIL project manager for NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Our two spacecraft are now sitting comfortably inside the payload fairing which will protect them during ascent. Next time the GRAIL twins will see the light of day they will be about 95 miles up and accelerating."
The spacecraft twins, GRAIL A and B, will fly a circuitous route to lunar orbit taking 3.5 months and covering approximately 2.6 million miles (4.2 million kilometers) for GRAIL-A, and 2.7 million miles (4.3 million kilometers) for GRAIL-B.
In lunar orbit, the spacecraft will transmit radio signals precisely defining the distance between them. Regional gravitational differences on the moon are expected to expand and contract that distance. GRAIL scientists will use these accurate measurements to define the moon's gravity field. The data will allow mission scientists to understand what goes on below the surface of our natural satellite.
"GRAIL will unlock lunar mysteries and help us understand how the moon, Earth and other rocky planets evolved as well," said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge.
GRAIL's launch period opens Sept. 8 and extends through Oct. 19. On each day, there are two separate launch opportunities separated by approximately 39 minutes. On Sept. 8, the first launch opportunity is 8:37 a.m. EDT; the second is 9:16 a.m.
JPL manages the GRAIL mission. It is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver, built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida.”
Thursday, August 25, 2011
IS NASA HAVING A MACBETH MOMENT
The picture of the three galaxies is fantastic. It reminds me of when MacBeth came across the three weird sisters. Maybe the future is in the stars. The following excerpt is from the NASA website:
"A Tale of Three Galaxies
Arp 274, also known as NGC 5679, is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (to the far left) is more compact, but shows evidence of star formation.
Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left.
The largest component is located in the middle of the three. It appears as a spiral galaxy, which may be barred. The entire system resides at about 400 million light-years away from Earth in the constellation Virgo.
Hubble’s Wide Field Planetary Camera 2 was used to image Arp 274 in April 2009. Blue, visible and infrared filters were combined with a filter that isolates hydrogen emission. The colors in this image reflect the intrinsic color of the different stellar populations that make up the galaxies. Yellowish older stars can be seen in the central bulge of each galaxy. A bright central cluster of stars pinpoint each nucleus. Younger blue stars trace the spiral arms, along with pinkish nebulae that are illuminated by new star formation. Interstellar dust is silhouetted against the starry population. A pair of foreground stars inside our own Milky Way are at far right."
"A Tale of Three Galaxies
Arp 274, also known as NGC 5679, is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (to the far left) is more compact, but shows evidence of star formation.
Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left.
The largest component is located in the middle of the three. It appears as a spiral galaxy, which may be barred. The entire system resides at about 400 million light-years away from Earth in the constellation Virgo.
Hubble’s Wide Field Planetary Camera 2 was used to image Arp 274 in April 2009. Blue, visible and infrared filters were combined with a filter that isolates hydrogen emission. The colors in this image reflect the intrinsic color of the different stellar populations that make up the galaxies. Yellowish older stars can be seen in the central bulge of each galaxy. A bright central cluster of stars pinpoint each nucleus. Younger blue stars trace the spiral arms, along with pinkish nebulae that are illuminated by new star formation. Interstellar dust is silhouetted against the starry population. A pair of foreground stars inside our own Milky Way are at far right."
BLACK HOLE DEVOURS STAR: STAR FACT OR STAR TREK
The following excerpt is from the NASA website. The picture of a black hole devourig a star seems to be something right out of a Star Trek or Doctor Who episode:
NASA'S Swift Satellite Spots Black Hole Devouring A Star
WASHINGTON -- Two studies appearing in the Aug. 25 issue of the journal Nature provide new insights into a cosmic accident that has been streaming X-rays toward Earth since late March. NASA's Swift satellite first alerted astronomers to intense and unusual high-energy flares from the new source in the constellation Draco.
"Incredibly, this source is still producing X-rays and may remain bright enough for Swift to observe into next year," said David Burrows, professor of astronomy at Penn State University and lead scientist for the mission's X-Ray Telescope instrument. "It behaves unlike anything we've seen before."
Astronomers soon realized the source, known as Swift J1644+57, was the result of a truly extraordinary event -- the awakening of a distant galaxy's dormant black hole as it shredded and consumed a star. The galaxy is so far away, it took the light from the event approximately 3.9 billion years to reach Earth.
Burrows' study included NASA scientists. It highlights the X- and gamma-ray observations from Swift and other detectors, including the Japan-led Monitor of All-sky X-ray Image (MAXI) instrument aboard the International Space Station.
The second study was led by Ashley Zauderer, a post-doctoral fellow at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. It examines the unprecedented outburst through observations from numerous ground-based radio observatories, including the National Radio Astronomy Observatory's Expanded Very Large Array (EVLA) near Socorro, N.M.
Most galaxies, including our own, possess a central supersized black hole weighing millions of times the sun's mass. According to the new studies, the black hole in the galaxy hosting Swift J1644+57 may be twice the mass of the four-million-solar-mass black hole in the center of the Milky Way galaxy. As a star falls toward a black hole, it is ripped apart by intense tides. The gas is corralled into a disk that swirls around the black hole and becomes rapidly heated to temperatures of millions of degrees.
The innermost gas in the disk spirals toward the black hole, where rapid motion and magnetism create dual, oppositely directed "funnels" through which some particles may escape. Jets driving matter at velocities greater than 90 percent the speed of light form along the black hole's spin axis. In the case of Swift J1644+57, one of these jets happened to point straight at Earth.
"The radio emission occurs when the outgoing jet slams into the interstellar environment," Zauderer explained. "By contrast, the X-rays arise much closer to the black hole, likely near the base of the jet."
Theoretical studies of tidally disrupted stars suggested they would appear as flares at optical and ultraviolet energies. The brightness and energy of a black hole's jet is greatly enhanced when viewed head-on. The phenomenon, called relativistic beaming, explains why Swift J1644+57 was seen at X-ray energies and appeared so strikingly luminous.
When first detected March 28, the flares were initially assumed to signal a gamma-ray burst, one of the nearly daily short blasts of high-energy radiation often associated with the death of a massive star and the birth of a black hole in the distant universe. But as the emission continued to brighten and flare, astronomers realized that the most plausible explanation was the tidal disruption of a sun-like star seen as beamed emission.
By March 30, EVLA observations by Zauderer's team showed a brightening radio source centered on a faint galaxy near Swift's position for the X-ray flares. These data provided the first conclusive evidence that the galaxy, the radio source and the Swift event were linked.
"Our observations show that the radio-emitting region is still expanding at more than half the speed of light," said Edo Berger, an associate professor of astrophysics at Harvard and a coauthor of the radio paper. "By tracking this expansion backward in time, we can confirm that the outflow formed at the same time as the Swift X-ray source."
Swift, launched in November 2004, is managed by NASA's Goddard Space Flight Center in Greenbelt, Md. It is operated in collaboration with Penn State, the Los Alamos National Laboratory in N.M. and Orbital Sciences Corp., in Dulles, Va., with international collaborators in the U.K., Italy, Germany and Japan. MAXI is operated by the Japan Aerospace Exploration Agency as an external experiment attached to the Kibo module of the space station."
NASA'S Swift Satellite Spots Black Hole Devouring A Star
WASHINGTON -- Two studies appearing in the Aug. 25 issue of the journal Nature provide new insights into a cosmic accident that has been streaming X-rays toward Earth since late March. NASA's Swift satellite first alerted astronomers to intense and unusual high-energy flares from the new source in the constellation Draco.
"Incredibly, this source is still producing X-rays and may remain bright enough for Swift to observe into next year," said David Burrows, professor of astronomy at Penn State University and lead scientist for the mission's X-Ray Telescope instrument. "It behaves unlike anything we've seen before."
Astronomers soon realized the source, known as Swift J1644+57, was the result of a truly extraordinary event -- the awakening of a distant galaxy's dormant black hole as it shredded and consumed a star. The galaxy is so far away, it took the light from the event approximately 3.9 billion years to reach Earth.
Burrows' study included NASA scientists. It highlights the X- and gamma-ray observations from Swift and other detectors, including the Japan-led Monitor of All-sky X-ray Image (MAXI) instrument aboard the International Space Station.
The second study was led by Ashley Zauderer, a post-doctoral fellow at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. It examines the unprecedented outburst through observations from numerous ground-based radio observatories, including the National Radio Astronomy Observatory's Expanded Very Large Array (EVLA) near Socorro, N.M.
Most galaxies, including our own, possess a central supersized black hole weighing millions of times the sun's mass. According to the new studies, the black hole in the galaxy hosting Swift J1644+57 may be twice the mass of the four-million-solar-mass black hole in the center of the Milky Way galaxy. As a star falls toward a black hole, it is ripped apart by intense tides. The gas is corralled into a disk that swirls around the black hole and becomes rapidly heated to temperatures of millions of degrees.
The innermost gas in the disk spirals toward the black hole, where rapid motion and magnetism create dual, oppositely directed "funnels" through which some particles may escape. Jets driving matter at velocities greater than 90 percent the speed of light form along the black hole's spin axis. In the case of Swift J1644+57, one of these jets happened to point straight at Earth.
"The radio emission occurs when the outgoing jet slams into the interstellar environment," Zauderer explained. "By contrast, the X-rays arise much closer to the black hole, likely near the base of the jet."
Theoretical studies of tidally disrupted stars suggested they would appear as flares at optical and ultraviolet energies. The brightness and energy of a black hole's jet is greatly enhanced when viewed head-on. The phenomenon, called relativistic beaming, explains why Swift J1644+57 was seen at X-ray energies and appeared so strikingly luminous.
When first detected March 28, the flares were initially assumed to signal a gamma-ray burst, one of the nearly daily short blasts of high-energy radiation often associated with the death of a massive star and the birth of a black hole in the distant universe. But as the emission continued to brighten and flare, astronomers realized that the most plausible explanation was the tidal disruption of a sun-like star seen as beamed emission.
By March 30, EVLA observations by Zauderer's team showed a brightening radio source centered on a faint galaxy near Swift's position for the X-ray flares. These data provided the first conclusive evidence that the galaxy, the radio source and the Swift event were linked.
"Our observations show that the radio-emitting region is still expanding at more than half the speed of light," said Edo Berger, an associate professor of astrophysics at Harvard and a coauthor of the radio paper. "By tracking this expansion backward in time, we can confirm that the outflow formed at the same time as the Swift X-ray source."
Swift, launched in November 2004, is managed by NASA's Goddard Space Flight Center in Greenbelt, Md. It is operated in collaboration with Penn State, the Los Alamos National Laboratory in N.M. and Orbital Sciences Corp., in Dulles, Va., with international collaborators in the U.K., Italy, Germany and Japan. MAXI is operated by the Japan Aerospace Exploration Agency as an external experiment attached to the Kibo module of the space station."
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