Comet Lovejoy can be seen in the video rising just right of the Milky Way.
Here’s a quick but lovely little gem: a time-lapse video taken from the ISS as it passed above central Africa, Madagascar and the southern Indian Ocean on December 29, 2011. The nighttime flyover shows numerous lightning storms and the thin band of our atmosphere, with a layer of airglow above, set against a stunning backdrop of the Milky Way and a barely-visible Comet Lovejoy, just two weeks after its close encounter with the Sun.
This video was made from photos taken by Expedition 30 astronauts. The photos were compiled at Johnson Space Center and uploaded to The Gateway to Astronaut Photography of Earth, an excellent database of… well, of astronauts’ photos of Earth.
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The site’s description of this particular video states:
This video was taken by the crew of Expedition 30 on board the International Space Station. The sequence of shots was taken December 29, 2011 from 20:55:05 to 21:14:09 GMT, on a pass from over central Africa, near southeast Niger, to the South Indian Ocean, southeast of Madagascar. The complete pass is over southern Africa to the ocean, focusing on the lightning flashes from local storms and the Milky Way rising over the horizon. The Milky Way can be spotted as a hazy band of white light at the beginning of the video. The pass continues southeast toward the Mozambique Channel and Madagascar. The Lovejoy Comet can be seen very faintly near the Milky Way. The pass ends as the sun is rising over the dark ocean.
There are lots more time-lapse videos on the Gateway as well, updated periodically. Check them out here.
Video courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center.
Those darn airplanes that leave their contrails and ruin a good astrophoto….except, wait! This one is awesome! From John Chumack’s vantage point earlier this month, two aircraft met up in the sky to fly across the waxing gibbous Moon. John provided a cropped inset to make it easier for all to see the jets. Great capture, John!
John’s details: captured on 01-06-2012 at 17:47pm E.S.T.
Canon Rebel Xsi DSLR & 300mm Lens @ F8, ISO 400,
1/800 second exposure
Want to get your astrophoto featured on Universe Today? Join our Flickr group, post in our Forum or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
The gravitational lens B1938+666 as seen in the infrared when observed with the 10-meter Keck II telescope. Credit: D. Lagattuta / W. M. Keck Observatory
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Astronomers can’t see it but they know it’s out there from the distortions caused by its gravity. That statement describes dark matter, the elusive substance which scientists have estimated makes up about 25% of our universe and doesn’t emit or absorb light. But it also describes a distant, tiny galaxy located about 10 billion light years from Earth. This galaxy can’t be seen in telescopes, but astronomers were able to detect its presence through the small distortions made in light that passes by it. This dark galaxy is the most distant and lowest-mass object ever detected, and astronomers say it could help them find similar objects and confirm or reject current cosmological theories about the structure of the Universe.
“Now we have one dark satellite [galaxy],” said Simona Vegetti, a postdoctoral researcher at the Massachusetts Institute of Technology, who led the discovery. “But suppose that we don’t find enough of them — then we will have to change the properties of dark matter. Or, we might find as many satellites as we see in the simulations, and that will tell us that dark matter has the properties we think it has.”
This dwarf galaxy is a satellite of a distant elliptical galaxy, called JVAS B1938 + 666. The team was looking for faint or dark satellites of distant galaxies using gravitational lensing, and made their observations with the Keck II telescope on Mauna Kea in Hawaii, along with the telescope’s adaptive optics to limit the distortions from our own atmosphere.
They found two galaxies aligned with each other, as viewed from Earth, and the nearer object’s gravitational field deflected the light from the more distant object (JVAS B1938 + 666) as the light passed through the dark galaxy’s gravitational field, creating a distorted image called an “Einstein Ring.”
Using data from this effect, the mass of the dark galaxy was found to be 200 million times the mass of the Sun, which is similar to the masses of the satellite galaxies found around our own Milky Way. The size, shape and brightness of the Einstein ring depends on the distribution of mass throughout the foreground lensing galaxy.
Current models suggest that the Milky Way should have about 10,000 satellite galaxies, but only 30 have been observed. “It could be that many of the satellite galaxies are made of dark matter, making them elusive to detect, or there may be a problem with the way we think galaxies form,” Vegetti said.
The dwarf galaxy is a satellite, meaning that it clings to the edges of a larger galaxy. Because it is small and most of the mass of galaxies is not made up of stars but of dark matter, distant objects such as this galaxy may be very faint or even completely dark.
“For several reasons, it didn’t manage to form many or any stars, and therefore it stayed dark,” said Vegetti.
Vegetti and her team plan to use the same method to look for more satellite galaxies in other regions of the Universe, which they hope will help them discover more information on how dark matter behaves.
Their research was published in this week’s edition of Nature.
NASA has published a new online gallery of beautifully restored photographs from the historic Project Gemini of the 1960s, the second U.S. manned spaceflight program. The digitally remastered photos have been scanned from the original film, showing highlights of Project Gemini in beautifully enhanced colour and detail.
Project Gemini followed the initial Project Mercury program and was the predecessor for the ambitious Apollo missions to the Moon, with ten crewed flights from 1965-1966. It used a two-man spacecraft and tested new technologies and procedures for the later Apollo missions such as precision atmospheric reentry, Extra Vehicular Activity (spacewalking), fuel cells to generate electricity and water, perfect the rendezvous and docking process between two spacecraft, new techniques for propelling and maneuvering two docked spacecraft and long-term human spaceflight.
It featured the first spacewalk, the first rendezvous between two Gemini spacecraft, the first docking between a manned and unmanned vehicle, the first maneuver to change orbit and the first onboard computer.
Gemini VII's rendezvous with Gemini VI. Credit: NASA / JSC / Arizona State University
The photo gallery is part of the March to the Moon website archive, which also has restored photo galleries from the Mercury missions as well as background information on the missions, Quicktime video clips and links to additional resources.
Ebb and Flow - New Names for the GRAIL Twins in Lunar Orbit. 4th Grade Students from Montana win NASA’s contest to rename the GRAIL A and GRAIL B spacecraft. Artist concept of twin GRAIL spacecraft flying in tandem orbits around the Moon to measure its gravity field in unprecedented detail and unravel the hidden mysteries of the lunar interior’s composition. Credit: NASA/JPL Montage:Ken Kremer
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A classroom of America’s Youth from an elementary school in Bozeman, Montana submitted the stellar winning entry in NASA’s nationwide student essay contest to rename the twin GRAIL lunar probes that just achieved orbit around our Moon on New Year’s Eve and New Year’s Day 2012
“Ebb” & “Flow” – are the dynamic duo’s official new names and were selected because they clearly illuminate the science goals of the gravity mapping spacecraft and how the Moon’s influence mightily affects Earth every day in a manner that’s easy for everyone to understand.
“The 28 students of Nina DiMauro’s class at the Emily Dickinson Elementary School have really hit the nail on the head,” said GRAIL principal investigator Prof. Maria Zuber of the Massachusetts Institute of Technology in Cambridge, Mass.
“We asked the youth of America to assist us in getting better names.”
“We chose Ebb and Flow because it’s the daily example of how the Moon’s gravity is working on the Earth,” said Zuber during a media briefing held today (Jan. 17) at NASA Headquarters in Washington, D.C. The terms ebb and flow refer to the movement of the tides on Earth due to the gravitational pull from the Moon.
“We were really impressed that the students drew their inspiration by researching GRAIL and its goal of measuring gravity. Ebb and Flow truly capture the spirit and excitement of our mission.”
Leland Melvin, NASA Associate Administrator for Education, left, Maria Zuber, GRAIL Prinicipal Investigator at the Massachusetts Institute of Technology, and James Green, Director of the Planetary Science Division in the Science Mission Directorate at NASA Headquarters, right, applaud students from Emily Dickinson Elementary School in Bozeman, Mont. during a news conference, Tuesday, Jan. 17, 2012, at NASA Headquarters in Washington. Nine hundred classrooms and more than 11,000 students from 45 states, as well as Puerto Rico and the District of Columbia, participated in a contest that began in October 2011 to name the twin lunar probes. Credit: NASA/Paul E. Alers
Ebb and Flow are flying in tandem around Earth’s only natural satellite, the first time such a feat has ever been attempted.
As they fly over mountains, craters and basins on the Moon, the spaceships will move back and forth in orbit in an “ebb and flow” like response to the changing lunar gravity field and transmit radio signals to precisely measure the variations to within 1 micron, the width of a red blood cell.
The breakthrough science expected from the mirror image twins will provide unprecedented insight into what lurks mysteriously hidden beneath the surface of our nearest neighbor and deep into the interior.
The winning names from the 4th Graders of Emily Dickinson Elementary School were chosen from essays submitted by nearly 900 classrooms across America with over 11,000 students from 45 states, Puerto Rico and the District of Columbia, Zuber explained.
The students themselves announced “Ebb” and “Flow” in a dramaric live broadcast televised on NASA TV via Skype.
“We are so thrilled that our names were chosen and excited to share this with you. We can’t believe we won! We are so honored. Thank you!” said Ms. DiMauro as the very enthusiastic students spelled out the names by holding up the individual letters one-by-one on big placards from their classroom desks in Montana.
Watch the 4th Grade Kids spell the names in this video!
Until now the pair of probes went by the rather uninspiring monikers of GRAIL “A” and “B”. GRAIL stands for Gravity Recovery And Interior Laboratory.
The twin crafts’ new names were selected jointly by Prof. Zuber and Dr. Sally Ride, America’s first woman astronaut, and announced during today’s NASA briefing.
NASA’s naming competition was open to K-12 students who submitted pairs of names and a short essay to justified their suggestions.
“Ebb” and “Flow” (GRAIL A and GRAIL B) are the size of washing machines and were launched side by side atop a Delta II booster rocket on September 10, 2011 from Cape Canaveral, Florida.
They followed a circuitous 3.5 month low energy path to the Moon to minimize the fuel requirements and overall costs.
So far the probes have completed three burns of their main engines aimed at lowering and circularizing their initial highly elliptical orbits. The orbital period has also been reduced from 11.5 hours to just under 4 hours as of today.
“The science phase begins in early March,” said Zuber. At that time the twins will be flying in tandem at 55 kilometers (34 miles) altitude.
The GRAIL twins are also equipped with a very special camera dubbed MoonKAM (Moon Knowledge Acquired by Middle school students) whose purpose is to inspire kids to study science.
“GRAIL is NASA’s first planetary spacecraft mission carrying instruments entirely dedicated to education and public outreach,” explained Sally Ride. “Over 2100 classrooms have signed up so far to participate.”
Thousands of middle school students in grades five through eight will select target areas on the lunar surface and send requests for study to the GRAIL MoonKAM Mission Operations Center in San Diego which is managed by Dr. Ride in collaboration with undergraduate students at the University of California in San Diego.
By having their names selected, the 4th graders from Emily Dickinson Elementary have also won the prize to choose the first target on the Moon to photograph with the MoonKam cameras, said Ride.
Zuber notes that the first MoonKAM images will be snapped shortly after the 82 day science phase begins on March 8.
Ebb & Flow Achieve Lunar Orbit on New Year’s Weekend 2012
NASA’s twin GRAIL-A & GRAIL-B spacecraft are orbiting the Moon in this astrophoto taken on Jan. 2, 2012 shortly after successful Lunar Orbit Insertions on New Year’s Eve and New Year’s Day 2012.
Credit: Ken Kremer
If you like math, music and space (separately or in any combination) you’re gonna love this. Musician Daniel Starr-Tambor has created a song by assigning each planet a note and speeding up the orbital periods of the planets where 2 seconds represents one Earth year, with a note playing for each orbit. But this isn’t just any typical song; it ends up being a musical palindrome, which means it can be played the same both forwards and backwards … that is, if you lived long enough to play to the end of the song. At the accelerated speeds of the Solar System, Starr-Tambor estimates it would continue without repetition for over 532.25 septendecillion years (5.3225 X 10 56). And with more than 62 vigintillion (6.2 X 10 64) individual notes, this composition, called “Mandala,” is the longest musical palindrome in existence.
Back in the 17th century composers like J.S. Bach created musical palindromes (mostly to show off!) and Starr-Tambor pays homage to Bach by choosing the precise position of the Solar System at the moment of Bach’s birth, viewed from the perspective of the Sun as it faces the constellation Libra, “so that each note chronicles his birthday on every planet.”
For those of us interested in the night sky, what could be better than having an astronomer for a friend? Well, how about if that astronomer friend has written a book detailing everything you can see in the night sky for every night of the year?
Universe Today’s very own Tammy Plotner has written that book, and it’s called “Night Sky Companion 2012.” Inside, you’ll find information on meteor showers, planetary alignments, lunar features, deep sky objects, eclipses, transits and more. Tammy has written the book in her unique conversational tone (well known to UT readers!) and provides all the information you’ll need – for those just looking up with their own eyes to those using binoculars or even larger telescopes.
Tammy’s book is available on Amazon in both print ($19.99 USD) and Kindle ($4.99) formats.
“Night Sky Companion 2012” has nightly information for both northern and southern hemispheres, and the book provides coordinates, basic star charts and realistic illustrations to help you find what you want to see, every night of the year.
Tammy is no stranger to writing books, as she has written several night sky guides over the years (see the complete list here). And of course, she is an award-winning astronomer, too!
“The ‘Night Sky Companion 2012’ is not just about finding objects in the night sky,” says Tammy, “ it teaches you both the science and history of what you’re looking at. How far away is that star? How deep is that crater on the Moon? What comet caused this meteor shower? It’s like having an astronomer as your best friend… One that’s with you every night!”
For a preview of the book, use the “Look Inside” feature on Amazon.com.
Titan's thick, smog-like upper atmosphere obscures our view of the lower atmosphere and surface. The much smaller moon Enceladus is also seen in this image. Credit: NASA/JPL
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Titan, the largest moon of Saturn, is in some ways the most Earth-like world in the solar system, with a thick nitrogen atmosphere, rain, rivers, lakes and seas. Albeit it is much colder, and liquid methane/ethane takes the place of water, but the hydrological processes are quite similar to those here. There may, however, also be a liquid water-ammonia ocean below the surface. Now, new research suggests that Titan is Earth-like in another way as well, with a layered lower atmosphere similar to ours.
It’s been long known that Titan has a dense atmosphere; you can’t even see the surface due to a thick smog-like upper haze composed of hydrocarbons. As it turns out, the lower atmosphere has two distinct layers; the lowest layer, like on Earth, is known as the boundary layer, which has the most influence on climate and weather.
There has been a lot of uncertainty about the nature of Titan’s lower atmosphere, so scientists developed a 3-D climate model to try to answer those questions – previous data from Voyager 1, Cassini and Huygens had led to conflicting results. This was largely due to the fact that the lower atmosphere can’t be observed directly because of the opaque upper atmosphere. The new climate model shows that there are two lower layers which are distinct from each other as well as from the upper atmosphere. The lowest boundary layer is about 800 metres (2,600 feet) thick while the next layer is about 2 kilometers (1.2 miles) deep.
According to Paulo Penteado from the Institute of Astronomy, Geophysics and Atmospheric Science at the University of São Paulo in Brazil, “The most interesting point is that their model shows the presence of two different boundaries, the lower one caused by the daily heating and cooling of the surface – and varying in height during the day – and the higher one caused by the seasonal change in global air circulation.”
Benjamin Charnay from the French National Centre for Scientific Research (CNRS) in Paris and lead author of the study, adds: “This unprecedented organisation of the boundary layer has several consequences. It controls the atmospheric circulation and wind patterns in the lower atmosphere; it controls the size and spacing of dunes on Titan; it could imply the formation of boundary layer clouds (of methane on Titan). Such clouds seem to have been observed but not explained.”
These differences are surprising, since Titan receives far less solar energy from the Sun than Earth does. This solar insulation, which determines temperature variations in the atmosphere, is 1,000 times weaker on Titan than on Earth. Such a dynamic atmosphere on Titan was unexpected, but it may hold clues as to the formation of our own atmosphere. This could also be extrapolated to exoplanets; if a smaller world so far from the Sun can have unanticipated Earth-like conditions, how many exoplanets, now being discovered by the thousands, could as well?
The findings were published in the January 15, 2012 issue of Nature Geoscience.
From the abstract:
“We conclude that Titan’s troposphere is well structured, featuring two boundary layers that control wind patterns, dune spacing and cloud formation at low altitudes.”
The abstract and article are here. The full article is available for $18.00 US or by subscription to Nature Geoscience.
Spitzer telescope view of the galactic center. (NASA/JPL-Caltech/S. Stolovy)
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“Sgr A* is the right object, VLBI is the right technique, and this decade is the right time.”
So states the mission page of the Event Horizon Telescope, an international endeavor that will combine the capabilities of over 50 radio telescopes across the globe to create a single Earth-sized telescope to image the enormous black hole at the center of our galaxy. For the first time, astronomers will “see” one of the most enigmatic objects in the Universe.
And tomorrow, January 18, researchers from around the world will convene in Tucson, AZ to discuss how to make this long-standing astronomical dream a reality.
During a conference organized by Dimitrios Psaltis, associate professor of astrophysics at the University of Arizona’s Steward Observatory, and Dan Marrone, an assistant professor of astronomy at the Steward Observatory, astrophysicists, scientists and researchers will gather to coordinate the ultimate goal of the Event Horizon Telescope; that is, an image of Sgr A*’s accretion disk and the “shadow” of its event horizon.
“Nobody has ever taken a picture of a black hole. We are going to do just that.”
– Dimitrios Psaltis, associate professor of astrophysics at the University of Arizona’s Steward Observatory
Sgr A* (pronounced as “Sagittarius A-star”) is a supermassive black hole residing at the center of the Milky Way. It is estimated to contain the equivalent mass of 4 million Suns, packed into an area smaller than the diameter of Mercury’s orbit.
Because of its proximity and estimated mass, Sgr A* presents the largest apparent event horizon size of any black hole candidate in the Universe. Still, its size in the sky is about the same as viewing “a grapefruit on the Moon.”
So what are astronomers expecting to actually “see”?
(Read more: What does a black hole look like?)
A black hole's "shadow", or event horizon. (NASA illustration)
Because black holes by definition are black – that is, invisible in all wavelengths of radiation due to the incredibly powerful gravitational effect on space-time around them – an image of the black hole itself will be impossible. But Sgr A*’s accretion disk should be visible to radio telescopes due to its billion-degree temperatures and powerful radio (as well as submillimeter, near infrared and X-ray) emissions… especially in the area leading up to and just at its event horizon. By imaging the glow of this super-hot disk astronomers hope to define Sgr A*’s Schwarzschild radius – its gravitational “point of no return”.
This is also commonly referred to as its shadow.
The position and existence of Sgr A* has been predicted by physics and inferred by the motions of stars around the galactic nucleus. And just last month a giant gas cloud was identified by researchers with the European Southern Observatory, traveling directly toward Sgr A*’s accretion disk. But, if the EHT project is successful, it will be the first time a black hole will be directly imaged in any shape or form.
“So far, we have indirect evidence that there is a black hole at the center of the Milky Way,” said Dimitrios Psaltis. “But once we see its shadow, there will be no doubt.”
Submillimeter Telescope on Mt. Graham, AZ. (Used with permission from University of Arizona, T. W. Folkers, photographer.)
The ambitious Event Horizon Telescope project will use not just one telescope but rather a combination of over 50 radio telescopes around the world, including the Submillimeter Telescope on Mt. Graham in Arizona, telescopes on Mauna Kea in Hawaii and the Combined Array for Research in Millimeter-wave Astronomy in California, as well as several radio telescopes in Europe, a 10-meter dish at the South Pole and, if all goes well, the 50-radio-antenna capabilities of the new Atacama Large Millimeter Array in Chile. This coordinated group effort will, in effect, turn our entire planet into one enormous dish for collecting radio emissions.
By using long-term observations with Very Long Baseline Interferometry (VLBI) at short (230-450 GHz) wavelengths, the EHT team predicts that the goal of imaging a black hole will be achieved within the next decade.
“What is great about the one in the center of the Milky Way is that is big enough and close enough,” said assistant professor Dan Marrone. “There are bigger ones in other galaxies, and there are closer ones, but they’re smaller. Ours is just the right combination of size and distance.”
Satellite view from the Advanced Land Imager on the Earth Observer 1, showing a brand new volcanic island in the Red Sea. Credit: NASA
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Want to get away from it all? Here’s the newest deserted island on Earth. In late December, we reported on a volcanic eruption in the Red Sea that appeared to have created a brand new island. The eruption has now stopped and on January 15, 2012 the Advanced Land Imager on the Earth Observer-1 satellite captured a clear, cloud- and volcanic plume-free view of this newly formed land mass. The new island is part of the Zubair Islands, located about 60 kilometers (40 miles) off the coast of Yemen. The new island and its older family members poke above the sea surface, rising from a shield volcano. This region is part of the Red Sea Rift where the African and Arabian tectonic plates pull apart and new ocean crust regularly forms.
If you want to visit, just watch out for hot lava pits and almost certain future eruptions.
