Posted on by Jason Major

NASA Prepares for Asteroid’s Close Pass by Earth

Radar image of asteroid 2005 YU55, acquired in April 2010. Credit: NASA/Cornell/Arecibo.

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On Tuesday, November 8, at 6:28 p.m. EST, an asteroid the size of an aircraft carrier will soar past our planet at a distance closer than the Moon… and NASA scientists will be watching!

2005 YU55, a 400-meter (1,300-foot) -wide C-type asteroid, was discovered in December 2005 by Robert McMillan of the Spacewatch Program at the University of Arizona, Tucson. It’s pretty much spherical in shape and dark – darker than charcoal, in fact! Scientists with NASA’s Near-Earth Objects Observation Program will begin tracking it on November 4 using the 70-meter radar telescope at the Deep Space Network in Goldstone, California , as well as with the Arecibo Planetary Radar Facility in Puerto Rico beginning November 8. They will continue tracking 2005 YU55 through November 10.

Animation of 2005 YU55's trajectory on Nov. 8. (NASA/JPL) Click to play.

YU55’s orbit is well understood by scientists. It has come this way before, and although this is the closest it’s come to Earth in at least two centuries it will still be at least 324,600 kilometers (201,700 miles) away at nearest approach. That’s about 85% of the distance to the Moon.

It will approach from the sunward side, making viewing in visible light difficult until after it’s made its closest pass.

Other than the excitement it will most likely cause amongst radar astronomers, 2005 YU55 will have no physical effect on our planet. (There have been some rumors circulating online about this particular asteroid’s upcoming pass, in regards to earthquakes and tidal fluctuations and atmospheric disturbances and other such nonsense… the bottom line is that, like the ill-fated comet Elenin, 2005 YU55 has never been known to pose any threat to Earth.)

“YU55 poses no threat of an Earth collision over, at the very least, the next 100 years,” said Don Yeomans, manager of NASA’s Near-Earth Object Program Office at JPL. “During its closest approach, its gravitational effect on the Earth will be so miniscule as to be immeasurable. It will not affect the tides or anything else.”

The 70m telescope at the Goldstone Deep Space Communications Complex in California's Mojave Desert. (NASA/JPL)

Scientists are very eager though to have a prime opportunity to study this quarter-mile-wide world as it makes its closest pass. The giant telescopes at Goldstone and Arecibo will bounce radar waves off the asteroid, mapping its size and shape, and hopefully obtain some very high-resolution images.

“Using the Goldstone radar operating with the software and hardware upgrades, the resulting images of YU55 could come in with resolution as fine as 4 meters per pixel. We’re talking about getting down to the kind of surface detail you dream of when you have a spacecraft fly by one of these targets.”

– Lance Benner, JPL radio astronomer

Even though YU55 will remain at a safe distance the event is still quite notable. The last time an object this large came so close to Earth was in 1976… and scientists weren’t even aware of it at the time. Luckily we now have programs like the Near-Earth Objects Observations Program – a.k.a. “Spaceguard” –  to identify asteroids like this, hopefully in time to know if they could become a danger to our planet in either the near or distant future.

As of now, no large space rock with Earth’s name on it has been positively identified… but that doesn’t mean there’s nothing out there either. We need to keep diligent, keep looking and, above all, keep funding programs like this. If anything, this pass should serve as a reminder – however harmless – that we certainly are not alone in the solar system!

Read more on the NASA/JPL press release here.

UPDATE: NASA will be holding a live Q&A on 2005 YU55 and other near-Earth objects on November 1 at 2:30 p.m. PDT (5:30 p.m. EDT)… watch live here.

 

 

Posted on by Jason Major

From the Land of Ice and Snow

Ice-coated mountaintops of Alexander Island, one of the largest islands off Antarctica. Credit: Michael Studinger/NASA.

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Views from the window of NASA’s DC-8 reveal sweeping expanses of ice and rock as part of the ongoing 2011 Operation IceBridge survey of Antarctica’s ice cover.

Now in its third season, Operation IceBridge is a six-year-long mission to study the dynamics of the Antarctic and Arctic ice sheets. It’s the largest ever aerial survey of the polar ice and will yield valuable data on the state of Earth’s vast reservoirs of frozen water, including the land and sea underneath and how they are being affected by today’s rapidly changing climate.

The ridges of the Shackleton Range cast shadows onto Antarctica's ice. Credit: Michael Studinger/NASA.

Researchers – like Michael Studinger, who took the incredible photos seen here –  fly over Greenland during the months of March through May and over Antarctica in October and November. NASA’s instrument-laden DC-8 flies over these remote locations at a low altitude of about 1,500 feet, often with little or no advance weather data.

98 percent of Antarctica is covered with ice. Information obtained by Operation IceBridge will be combined with satellite data to create the most accurate models possible of Antarctic ice loss and how it will affect future sea level rise.

Mountains piled with snow and ice rise above the clouds on Alexander Island. Credit: Michael Studinger/NASA.

This season’s Antarctic IceBridge campaign features NASA’s DC-8, at 157 feet long the largest plane in the agency’s airborne research fleet, and will also feature the debut of the Gulfstream V (G-V) operated by the National Science Foundation and National Center for Atmospheric Research.

While the DC-8 flies at low altitudes, the G-V will fly above 30,000 feet to utilize its Land, Vegetation and Ice Sensor (LVIS), which makes detailed topographic studies of the surface.

“With IceBridge, our aim is to understand what the world’s major ice sheets could contribute to sea-level rise. To understand that you have to record how ice sheets and glaciers are changing over time.”

– Michael Studinger, IceBridge project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.

The wing of NASA's DC-8 cuts across the frozen expanse of the Brunt Ice Shelf, with its 100-foot-high cliff face. Credit: Michael Studinger/NASA.

Read more about Operation IceBridge here.

Posted on by Jason Major

The Meteor and the Nordlys

Photo of the northern lights over northern Norway by Adon Buckley.

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A meteor slices through the glow of the northern lights (or “Nordlys”) in this photo by Adon Buckley, taken near the border of Norway and Finland on the night of October 19, 2011.

“The weather was against us, it was raining heavily in the northern Norwegian town of Tromsø,” Adon describes on his Flickr page. “We drove for 2 hours and waited on the Norwegian/Finish border for 3 more and this was at the start of the show on October 19th.”

He adds, “I actually missed the shooting star when it happened, but my friend told me and I was eager to check the exposure when I got home.”

Great catch, Adon! And a wonderful photo as well.

See more of Adon’s photos on his Flickr photostream here.

Image © Adon Buckley. Used with permission.

Posted on by Jason Major

Failed Star Is One Cool Companion

Artist's impression of a brown-dwarf object (left foreground) orbiting a distant white dwarf --the collapsed-core remnant of a dying star.

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Astronomers have located a planet-like star that’s barely warmer than a balmy summer day on Earth… it’s literally the coldest object ever directly imaged outside of our solar system!

WD 0806-661 B is a brown “Y dwarf” star that’s a member of a binary pair. Its companion is a much hotter white dwarf, the remains of a Sun-like star that has shed its outer layers. The pair is located about 63 light-years away, which is pretty close to us as stars go. The stars were identified by a team led by Penn State Associate Professor of Astronomy and Astrophysics Kevin Luhman using images from NASA’s Spitzer Space Telescope. Two infrared images taken in 2004 and 2009 were overlaid on top of each other and show the stars moving in tandem, indicating a shared orbit.

These two infrared images were taken by the Spitzer Space Telescope in 2004 and 2009. They show a faint object moving through space together with a white dwarf. Credit: Kevin Luhman, Penn State University, October 2011. (Click to play.)

Of course, locating the stars wasn’t quite as easy as that. To find this stellar duo Luhman and his team searched through over six hundred images of stars located near our solar system taken years apart, looking for any shifting position as a pair.

The use of infrared imaging allowed the team to locate a dim brown dwarf star like WD 0806-661 B, which emits little visible light but shines brightly in infrared. (Even though brown dwarfs are extremely cool for stars they are still much warmer than the surrounding space. And, for the record, brown dwarfs are not actually brown.) Measurements estimate the temperature of WD 0806-661 B to be in the range of about 80 to 130 degrees Fahrenheit (26 to 54 degrees C, or 300 – 345 K)… literally body temperature!

“Essentially, what we have found is a very small star with an atmospheric temperature about cool as the Earth’s.”

– Kevin Luhman, Associate Professor of Astronomy and Astrophysics, Penn State

Six to nine times the mass of Jupiter, WD 0806-661 B is more like a planet than a star. It never accumulated enough mass to ignite thermonuclear reactions and thus more resembles a gas giant like Jupiter or Saturn. But its origins are most likely star-like, as its distance from its white dwarf companion – about 2,500 astronomical units – indicates that it developed on its own rather than forming from the other star’s disc.

There is a small chance, though, that it did form as a planet and gradually migrated out to its current distance. More research will help determine whether this may have been the case.

Brown dwarfs, first discovered in 1995, are valuable research targets because they are the next best thing to studying cool atmospheres on planets outside our solar system. Scientists keep trying to locate new record-holders for the coldest brown dwarfs, and with the discovery of WD 0806-661 B Luhman’s team has done just that!

A paper covering the team’s findings will be published in The Astrophysical Journal. Other authors of the paper include Ivo Labbé, Andrew J. Monson and Eric Persson of the Observatories of the Carnegie Institution for Science, Pasadena, Calif.; Didier Saumon of the Los Alamos National Laboratory, New Mexico; Mark S. Marley of the NASA Ames Research Center, Moffett Field, Calif.; and John J. Bochanski also of The Pennsylvania State University.

Read more on the Penn State science site here.

 

Posted on by Jason Major

All Together Now!

Six main rocket engines from the Endeavour and Atlantis shuttles. Credit: NASA/Dimitri Gerondidakis

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That’s a lot of power under one roof! For the first time in… well, ever… all fifteen Space Shuttle Main Engines (SSMEs) are together inside NASA’s Engine Shop at Kennedy Space Center. They will be prepped for shipment to Stennis Space Center in Mississippi where they’ll become part of the propulsion used on NASA’s next generation heavy-lift rocket: the Space Launch System.

The engines, built by Pratt & Whitney Rocketdyne, are each 14 feet (4.2 meters) long & 7.5 feet (2.3 meters) in diameter at the end of its nozzle, and weighs approximately 7,000 lbs (3175 kg).

Photo from a test firing of an SSME at the Stennis Space Center in 1981. Credit: NASA.

Each engine is capable of generating a force of nearly 400,000 pounds (lbf) of thrust at liftoff, and consumes 350 gallons (1,340 liters) of fuel per second. They are engineered to burn liquid hydrogen and liquid oxygen, creating exhaust composed primarily of water vapor.

The engines will be incorporated into the Space Launch System (SLS), which is designed to carry the Orion Multi-Purpose Crew Vehicle – also currently in development – as well as serve as backup for commercial and international transportation to the ISS. By utilizing current technology and adapting it for future needs, NASA will be able to make the next leap in human spaceflight and space exploration – while getting the most “bang” out of the taxpayers’ bucks.

“NASA has been making steady progress toward realizing the president’s goal of deep space exploration, while doing so in a more affordable way. We have been driving down the costs on the Space Launch System and Orion contracts by adopting new ways of doing business and project hundreds of millions of dollars of savings each year.” 

–  NASA Deputy Administrator Lori Garver

Nine of the 15 SSMEs await shipment inside NASA's Engine Shop. Each weighs approximately 7,000 lbs. Credit: NASA.

While it’s sad to see these amazing machines removed from the shuttles, it’s good to know that they still have plenty of life left in them and will soon once again be able to take people into orbit and beyond!

Read more about the Space Launch System here.

Posted on by Jason Major

America vs. Astronaut: The Case of the Lifted Lunar Camera

Apollo 14 astronaut Ed Mitchell on the Moon, February 5, 1971. Credit: NASA.

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Imagine you’re an astronaut. You have what it takes to be selected to fly a mission to the Moon. You train, make the trip, and become one of literally a handful of humans ever to have walked on the lunar surface. And when you leave the desolate beauty of the Moon behind in your Landing Module, and are just about to re-enter the Lunar Orbiter and head for home, you see one of the cameras that you used on the surface. If you leave it where it is it’s going to be lost forever, crashing into the lunar surface with the rest of the lander. If you take it, you’ll be going against standard NASA operating procedure since you hadn’t filled out the proper paperwork beforehand for official mission items appropriated by astronauts. Leave a piece of history behind to be destroyed or salvage it as a souvenir… what do you do?

Apollo 14 astronaut Edgar Mitchell decided to bring the camera back, and now, 40 years later, his decision is going to land him in court.

Last June, the U.S. government brought a case against the 81-year-old moonwalker after he offered the 16-millimeter Data Acquisition Camera (DAC) up for sale at New York’s Bonhams auction house as part of their May “Space History Sale”. While it was common for Apollo astronauts to be able to keep various pieces of equipment and space suits as mementos after their missions, certain paperwork had to be filled out beforehand… it’s just the NASA way.

The late Donald “Deke” Slayton, head of the astronaut corps in 1971, mentioned this during an interview with the Tuscon Daily Citizen in 1972.

“They give me a list of things they’re going to bring back,” Slayton said. “I give it to the program office and they bring ’em back.”

This Data Acquisition Camera (DAC) was one of two 16mm cameras on the Apollo 14 lunar module "Antares" when it landed on the moon on Feb, 5, 1971. Credit: Bonhams.

The DAC, it seems, was not on any lists handed in by Mitchell. Yet it was never intended to be on the ride back to Earth, either. Rather its destination was to be in the bottom of a crater made by the landing module when it crashed back onto the Moon.

Must have seemed a rather wasteful end for a historic – and valuable – piece of equipment. Were it to go to auction it could have fetched between $60,000 to $80,000.

“We had an agreement with NASA management, that small items that didn’t exceed our weight limitations, we could bring back.”

– Edgar Mitchell to WPTV

Regardless of its value – sentimental or otherwise – NASA’s lawyer claims that Mitchell was contacted several times about returning the camera but never responded. Mitchell’s attorney, on the other hand, argues that too many years have passed for NASA to now claim the camera as stolen property.

When it was brought before a Florida district court judge to have the case dismissed, however, the judge had no option but to side with the government.

“‘It is well settled that the United States is not bound by state statutes of limitation or subject to the defense of laches in enforcing its rights,'” quoted Judge Daniel Hurley of an appeals court ruling. “Defendant’s allegations that NASA intended the camera to be destroyed after the mission or that it routinely awarded used mission equipment to astronauts do not preclude as a matter of law Plaintiff’s contrary allegation that Defendant impermissibly converted the camera.”

Bottom line: the case goes in front of a jury in October 2012.

Read more about this on collectSPACE.com.

Posted on by Jason Major

A Meteorite Visits the Comettes

This 88-gram (3.5 oz.) meteorite broke through the roof of the Comette family

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When your last name is Comette, I’m sure the occasional astronomy-themed joke is never far away. But it’s no joke that the Comette family living in Draveil, a suburb south of Paris, was paid a visit by a real extraterrestrial a couple of weeks ago – in the form of an 88-gram (3.5 oz.) meteorite that broke through their roof!

The Comettes were on vacation at the time, so didn’t realize their house had been struck by a space rock until they noticed a leak in the roof. When they called in a roofer it was discovered that a thick tile had been completely broken through.

The meteorite was found wedged in insulation.

Mineral scientist Alain Carion investigated the meteorite and determined that it’s an iron-rich chondrite, a 4.57-billion-year-old remnant of the early Solar System that most likely came from the main asteroid belt between the orbits of Mars and Jupiter. About 3/4 of all meteorites that have been observed landing on Earth are chondrites.

While obviously not impossible, the odds of your home being hit my a meteorite are incredibly slim. Only 145 meteorites have been documented landing in the US in the past 200 years. On March 26, 2003, just before midnight, hundreds of fragments of a large meteorite fell in the Park Forest area of Chicago. Several fell through roofs of houses and one punched a hole in the roof of the fire station. One large piece weighing about 2.5 kg (5.5 lb) crashed into a bedroom, narrowly missing a boy who was asleep in his bed! On September 23, 2003, a 20 kg (44 lb) stone meteorite tore straight through a two-storey house in New Orleans and came to rest in the basement. (Source: University of New Mexico Institute of Meteoritics.)

Only about 50 meteorites have been found in France over the past four centuries, and none has ever before been discovered less than 80 km (50 miles) from Paris.

While they could attempt to sell the meteorite that struck their home, possibly fetching several hundred euros for it, the Comettes have decided to keep their otherworldly visitor.

“A piece of the history of space of which we know nothing, but which is fascinating, has fallen on us,” Mrs. Comette told the Le Parisien newspaper. “It’s like a fairytale, and less likely than winning the lottery, we’re told.”

Read more on The Guardian or on The Local.

Image found on Stargazers Lounge.

Posted on by Jason Major

What is Vision? (A Save The James Webb Support Video)

Promotional poster supporting the JWST

Do you love astronomy? Do you appreciate science? Do you have a curiosity about the nature of our Universe, how it came to be and what our place is within it? If you are even reading this I assume your answers to all of those questions is a resounding “yes!” and so I present to you an excellent video created by Brad Goodspeed in support of the James Webb Space Telescope:

“I made Vision because I thought the argument for science could benefit from a passionate delivery,” Brad told Universe Today. “Deep down we’re all moved by the stars, and that passion needs to be expressed by methods outside of science’s typical toolbox.”

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Funding for this next-generation telescope is currently on the line in Washington. While a markup bill was passed last month by the House of Representatives that allows for continued funding of the JWST through to launch, it has not yet been ratified by Congress. It’s still very important to maintain support for the JWST by contacting your state representatives and letting them know that the future of space exploration is of concern to you.

A petition against the defunding of the JWST is currently active on Change.org and needs your signature (if you haven’t signed it already.) Signing ends at midnight tonight so be sure to click here to sign and pass it along as well! (You can share this shortened link on Twitter, Facebook, etc.: http://chn.ge/oy4ibI)

You can also show your support and follow the JWST progress by following Save the James Webb Space Telescope on Facebook and on saveJWST.com.

The JWST will be the premier observatory of the next decade, serving thousands of astronomers worldwide. It will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System. It is currently aiming for a 2018 launch date.

“We don’t get to the future by yielding to our most current fears… by being shortsighted.”

Video courtesy of Brad Goodspeed.

Posted on by Jason Major

What is Airglow?

Recent photo from the ISS showing the airglow layer

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In many of the photos that we have featured recently from astronauts aboard the International Space Station, a glowing greenish-yellow band can be seen just above Earth’s limb. I’ve been asked before what this is, so I thought I’d explain it here. This is a phenomenon known as “airglow”.

A photochemical reaction that occurs high in the atmosphere, airglow is the result of various atoms, molecules and ions that get excited (chemistry-excited, that is… not “whee!”-excited) by ultraviolet radiation from the Sun and then release that energy as visible – as well as infrared – light when they return to their “normal” state. It’s not entirely unlike glow-in-the-dark toys or paint!

This light is most visible to the crew of the ISS when it is orbiting over the night side of the planet, and thus is seen in images like the one above. It appears like a thin band because viewing the atmosphere at a shallow angle – rather than directly down through it – increases the airglow layer’s relative visibility.

Most of visible airglow comes from oxygen atoms and molecules, which glow green… as commonly seen in the aurora. Other contributing elements include sodium and nitrogen. While present in the atmosphere at all layers, the region that glows visibly is typically constrained to a narrow band 85 – 95km (53-60 miles) high. The band itself is usually about 6 – 10km (4-6 miles) wide. The reason for this is that below those heights the atoms and molecules are more concentrated and collide more readily, releasing their energy sooner, and above it the density of the atoms is too low to do much colliding at all (to put it very simply.)

There are a lot of other factors involved with airglow as well, such as temperature and altitude, as well as different kinds of airglow depending on when in the day they occur. Nightglow is not exactly the same as dayglow, and then there’s even twilightglow… one could say there’s a lot glowing on in the upper atmosphere!

I’m here all week, folks.

You can read more about airglow in this informative article by the Institute of Astronomy and Astrophysics (Instituto de Astronomía y Física del Espacio) in Buenos Aires. Image credit: NASA.