Posted on by Jon Voisey

Another Kepler Planet Confirmed

Artist's concept of Kepler in action. NASA/Kepler mission/Wendy Stenzel.

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The Kepler mission, launched in 2009, is looking to greatly improve our understanding of planets. Since beginning operation, the planet hunting spacecraft has made tentative identifications of over 1,200 planets, having spotted them as they transited their parent stars. However, these planets need confirmation from a more robust method, specifically the spectroscopically detected wobbles, before they’re added to the official list of extrasolar planets.

Thus far, confirmations have been slow to come; only 16 of the planets have been detected using other methods. But recently, astronomers using the Hobby-Eberly Telescope (HET), operated by the University of Texas, Austin have confirmed another.

The planet, Kepler-15b, is the first confirmed by this unique telescope. As opposed to most observatories, the mirror at the HET does not track the stars. Instead, the mirror remains stationary and the detecting instruments are moved along the focal plane to track the object in question. While this doesn’t allow for the object to track the entire night, it does let astronomers get continuous observation of the target for up to 2 hours. This unusual configuration was estimated to reduce the construction costs by as much as 80%.

From the Kepler observations, the tentative planet was expected to have an orbital period of just under 5 days and would transit the parent star for 3.5 hours, dimming the star’s light by about 1.2%. Using this information, the expectation was that the planet should have a radius of 1.4 times that of Jupiter, putting it in the class of “hot-Jupiters”.

The observations by the HET were taken from March until November of 2010. The team used the telescope’s spectrometer to search for the signs of variation between 2 and 100 days. When analyzed for periodicity, the team independently confirmed a strong signal with a period of 4.94 days.

Using the new spectroscopic data, the team estimates the new planet has a mass of 0.66 Jupiter masses, and reduces the estimated radius to 0.96 times that of Jupiter, giving a mean density of ~.9 grams per cubic centimeter. The parent star contains high amounts of heavy elements and is tied with Kepler-6 for the most metal rich parent star of the Kepler findings. If the planet, being formed from the same interstellar cloud, has similar metallicity, then it could be expected that the presence of these additional heavy elements could help to shrink the planet.

The team also reports that they have observed other purported Kepler planets and intends to include the findings in an upcoming publication. Additionally, the HET is scheduled for a major upgrade starting later this year. This will include upgrades to the tracking assembly, as well as the fiber optics used in the spectroscope. Currently, this instrument is only capable of performing confirmations for Jovian massed planets, but once upgrades are complete, the team expects to be able to use the system to search for lower mass candidates in the mass range of Neptune and those in the “Super-Earth” category.

Posted on by Tammy Plotner

New Kids On The Block – The Brown Dwarfs

False-colour images of the two brown dwarf discoveries WISE J0254+0223 and WISE J1741+2553. (Credit: AIP, NASA/IPAC Infrared Science Archive)

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When it comes to being close to “home”, there are not a lot of stars out there in our general neighborhood. Proxima Centauri is 4.2 light years away and Rigil Kentaurus is 4.3. There’s Barnard’s Star, Wolf 359, Lalande 21185, Luyten 726-8A and B and big, bright Sirius A and B. But what about a celestial neighbor that’s not quite so prominent? Try a pair of newly discovered brown dwarfs.

Scientists from the Leibniz Institute for Astrophysics Potsdam (AIP) using the NASA satellite WISE (Wide-field Infrared Survey Explorer) have discovered this unlikely duo just 15 and 18 light years from our solar system. “We have used the preliminary data release from WISE, selected bright candidates with colours typical of late-T dwarfs, tried to match them with faint 2MASS and SDSS objects, to determine their proper motions, and to follow-up them spectroscopically.” says RD Scholz, et al.

Named WISE J0254+0223 and WISE J1741+2553, the pair drew attention to themselves by their very disparity – one very bright in infrared and the other very faint in optical light. Even more attractive was the speed at which they’re moving – the proper motion changing drastically between observations. “The very large proper motions are a first hint that these objects should be very close to the Sun. Both objects are only detected in the SDSS z-band which is typical of nearby late-T dwarfs.” says Scholz.

Because the pair were optically visible at the time of the discovery, the team employed the Large Binocular Telescope (LBT) in Arizona to determine their spectral type and home in more accurately on their distance. They wanted to know more about the coolest representatives of T-type brown dwarf – the ultra-cool ones. Better known as failed stars because they lacked the mass to ignite nuclear fusion, the duo required study because their magnitude decreases sharply with time. Because they fade so quickly, there’s a strong possibility of a brown dwarf being much closer than we realize.

Like maybe next door…

Original News Source: Leibniz Institute for Astrophysics Potsdam News. For further reading: Cornell University Library – Two very nearby (d ~ 5 pc) ultracool brown dwarfs detected by their large proper motions from WISE, 2MASS, and SDSS data.

Posted on by Tammy Plotner

Are The Galaxies In Our Universe More Right-Handed… Or Left-Handed?

A new study found an excess of counter-clockwise rotating or "left-handed" spiral galaxies like this one, compared to their right-handed counterparts. This provides evidence that the universe does not have mirror symmetry. Credit: NASA, ESA

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It’s called mirror symmetry and it has everything to do with a recent study done by physics professor Michael Longo and a team of five undergraduates from the University of Michigan. Their work encompasses the rotation direction of tens of thousands of spiral galaxies cataloged by the Sloan Digital Sky Survey. What they’re looking for is the shape of the Big Bang… and what they found is much more elaborate than they thought.

By utilizing SDSS images, the team began looking for mirror symmetry and evidence the early universe spun on an axis. “The mirror image of a counter-clockwise rotating galaxy would have clockwise rotation. More of one type than the other would be evidence for a breakdown of symmetry, or, in physics speak, a parity violation on cosmic scales.” Longo said. However, there seems to be a certain “spin preference” when it comes to spiral galaxies toward the north pole of the Milky Way. Here they found an abundance of left-handed, or counter-clockwise rotating, spirals – an effect which extended beyond an additional 600 million light years.

“The excess is small, about 7 percent, but the chance that it could be a cosmic accident is something like one in a million,” Longo said. “These results are extremely important because they appear to contradict the almost universally accepted notion that on sufficiently large scales the universe is isotropic, with no special direction.”

On the other hand, be it left or right, Galaxy Zoo has done some very interesting research into mirror symmetry as well. In conjunction with the Sloan Digital Sky Survey, the team also involved the public for their input – a total of 36 million classifications for 893,212 galaxies from 85,276 users. The GZ study is absolutely fascinating and took every variable into account.

“We wish to establish the large scale statistical properties of the galaxy spins. Although there is some level of uncertainty in the overall number counts, it is still possible to look for a dipole, for example, in the spin distributions.” says Kate Land, et al. “Curiously, the dipoles from these two analyses are in completely opposite directions. The samples cover different amounts and parts of the sky, with SDSS mainly in the Northern hemisphere and the sample of Sugai & Iye (1995) predominantly in the Southern hemisphere. In both cases the dipoles tend to point away from the majority of the data but neither analysis fits for a monopole or takes account of their partial sky coverage in assessing the dipole. With incomplete sky coverage the spherical harmonic decomposition is no longer orthogonal and for a sample covering less than half of the sky it is hard to tell the difference between a monopole (an excess of one type over the other) and a dipole (an asymmetry in the distribution).”

So what’s the end result? Well, chances are good that our universe was born spinning… but like any family, there isn’t much evidence one way or another that says most members have to be right – or left – handed. It’s more about how we, as humans, perceive them…

Original Story Source: University of Michigan New Service. For further information, read Galaxy Zoo: The large-scale spin statistics of spiral galaxies in the Sloan Digital Sky Survey.

Posted on by Nancy Atkinson

Looming Larger: Dawn Approaches Vesta, Enters Orbit July 15-16

NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 9, 2011. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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As we anticipate the Dawn spacecraft going into orbit of Vesta within the next 36 hours, here’s the latest image taken as the spacecraft approaches Vesta, taken on July 9 from a distance of about 41,000 kilometers (26,000 miles). Surface details are coming into focus a little more than from the previous image that was released. The Dawn mission is exciting, as it will be the first spacecraft to enter orbit around a main-belt asteroid, and as we’ve said before, it will be intriguing for scientists to study this lumpy little world in detail and perhaps figuring out what Vesta really is.

Below is an “enhanced” look at this view of Vesta by Stu Atkinson.

Some astronomers classify Vesta as an asteroid, some a protoplanet, and some are on the fence. It’s not really considered a dwarf planet, but the classification could be re-evaluated when Dawn gets in orbit of Vesta and studies it in detail.

An enhanced view of Vesta from the July 9, 2011 image taken by the Dawn spacecraft. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, enhancements by Stu Atkinson.

Stu sent us this image with the caveat that he created it for his own amusement/entertainment, and that it’s not a scientifically enhanced image — i.e., it’s not to be 100% relied upon for feature identification, etc. But it’s a little clearer and sharper than the original from NASA/JPL. Thanks Stu!

Engineers expect the spacecraft to be captured into orbit at approximately 10 p.m. PDT Friday, July 15 (1 a.m. EDT Saturday, July 16). They expect to hear from the spacecraft and confirm that it performed as planned during a scheduled communications pass that starts at approximately 11:30 p.m. PDT on Saturday, July 16 (2:30 a.m. EDT Sunday, July 17). When Vesta captures Dawn into its orbit, engineers estimate there will be approximately 9,900 miles (16,000 kilometers) between the spacecraft and Vesta. At that point, the two will be approximately 117 million miles (188 million kilometers) from Earth.

“It has taken nearly four years to get to this point,” said Robert Mase, Dawn project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Our latest tests and check-outs show that Dawn is right on target and performing normally.”

Engineers have been subtly shaping Dawn’s trajectory for years to match Vesta’s orbit around the sun with its ion engine. Unlike other missions, where dramatic propulsive burns put spacecraft into orbit around a planet, Dawn will ease up next to Vesta. Then the asteroid’s gravity will capture the spacecraft into orbit. However, until Dawn nears Vesta and makes accurate measurements, the asteroid’s mass and gravity will only be estimates. So the Dawn team will need a few days to refine the exact moment of orbit capture.

Launched in September 2007, Dawn will depart for its second destination, the dwarf planet Ceres, in July 2012. The spacecraft will be the first to orbit two bodies in our solar system.

Stay tuned for more details and updates on the Dawn mission.

Source: JPL

Posted on by Jon Voisey

More Images of HR 8799

HR 8799 system
One of the discovery images of the system obtained at the Keck II telescope using adaptive optics system and the NIRC2 Near-Infrared Imager. Image shows all four confirmed planets indicated as b, c, d and e in the labeled image. Planet "b" is a ~5 Jupiter-mass planet orbiting at about ~68 AU, while planets c, d, and e are ~7 Jupiter-mass companions orbiting the star at about 38, 24 and 14.5 AU. Credit: NRC-HIA, C. Marois & Keck Observatory

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Late last year, astronomers using the Keck II telescope released the first direct image of a planetary system including four planets. These planets orbited the star HR 8799 and were taken in the J and L bandpasses which are in the near-infrared portion of the spectrum. Since then the team has collected new data using the same telescope, extending the spectral range into the mid-infrared portion of the spectra.

The new images are important to astronomers because this provides a more complete understanding of the distribution of radiation that the planets are emitting. This can be compared to models of planetary formation, allowing these young planets to act as a test bed. Previous comparison to models have suggested that these planets have cool, dusty atmospheres without the presence of methane or other common absorbing molecules.

The team hopes that the new observations will help distinguish between the various models that explain this deficiency of methane. Unfortunately, getting good observations in this portion of the spectra is challenging. In particular, at the Keck telescope, the design of the telescope itself makes observations especially challenging due to portions of the instrument themselves emitting in the infrared, masking the faint signals from the planet.

To bring out the planets, the team developed a new technique to help clean the images of the unwanted noise. They estimate that their new technique is nine times more efficient than previously used techniques. To do this, they moved the telescope slightly between images, allowing the patterns of interference to change between exposures, thereby making them more apparent and easier to remove.

When the results were analyzed and compared to models, the team found that they were in good agreement with predictions of planetary evolution for planets c and d. However, for planet b, the models predicted a planet with a radius that would be too small to account for the observed luminosity. The observations could be brought into agreement with the models by increasing the metallicity of the model.

With additional future observations, the team hopes to constrain these models and further investigate the atmospheres of these planets.

NOTE: I Emailed the authors of the paper to ask permission to reproduce the new image here, but have not gotten a reply. The one used above is the K and L band images from last year. To see the new ones, feel free to go to the paper directly.

Posted on by Jason Rhian

Return of the Capsule

SpaceX's Dragon Spacecraft was placed on display just outside of Cape Canaveral Air Force Station at the Space & Missile History Center. Photo Credit: Jason Rhian

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CAPE CANAVERAL Fla. – As Florida’s Space Coast braces for the end of the shuttle program this month, signs of life after shuttle are starting to emerge. Space Exploration Technologies (SpaceX) returned the Dragon Spacecraft that launched this past December to Cape Canaveral Air Force Station. The Dragon however, was not alone. Two more capsules, one a test article, the other a mock-up were on display at Kennedy Space Center’s press site, signaling the coming way of the future for human spaceflight.

The Dragon Spacecraft was on display outside of Cape Canaveral Air Force Station. Placed between SpaceX’s Launch Control Center (LCC) and the U.S. Air Force Space and Missile History Center, the Dragon’s scorched hull was displayed to remind Space Coast residents that the space program was not retiring along with the shuttles.

Spce Exploraton Technologies Vice-President of Communiatons, Bobby Block explains the reason the Dragon Spacecaft was returned to Cape Canaveral. Photo Credit: Jason Rhian

“A lot of people are sad that the shuttle program is ending, it has been such an integral part of the area for three decades that they have a right to feel this way,” said SpaceX’s Vice President of Communications, Bobby Block. “Just because the shuttles are retiring however, does not mean that the entire space program is ending – it’s not over – it is the ending of one program, but it also is the start of another.”

That sentiment was shared by Lockheed Martin who brought their Orion Multi-Purpose Crew Vehicle to sit near the iconic Countdown Clock, a mere 3.5 miles away from shuttle Atlantis out at Launch Complex 39A. At first glance the fact that the capsule was still chained to the back of a trailer appeared to suggest that its appearance was rushed but in fact it highlighted a campaign by Lockheed Martin to let the public view Orion.

In conjunction with the final launch of the shuttle program, Lockheed-Martin had the Orion MPCV on display at the Kennedy Space Center press site. Photo Credit: Jason Rhian

“We were taking the Orion to Kennedy Space Center so we took the opportunity to stop along the way,” said Lockheed Martin’s Communications Manager for the Orion Project Linda Singleton. “This way we could tell the public about the Orion Program, let them see the spacecraft first hand. We stopped at Tucson, Austin and Tallahassee and met with 20,000 people in person across the country and talked to them about Orion.”

Not to be outdone, the Boeing Company had a replica of its CST-100 Space Taxi – split down the middle allowing guests to get an up close and in-depth look at the capsule-concept that it is submitting, in collaboration with Bigelow Aerospace, as their entry for NASA’s Commercial Crew Development (CCDev) program. If chosen, it would be used to ferry astronauts to the International Space Station. Boeing also had a structural article on display nearby.

The interior of the mock up for the CST-100 highlights the relatively simple design planned for the spacecraft. Photo Credit: Jason Rhian

“The reason we selected a capsule is that it is a simple system, we’ve been flown since John Glenn did his first flight on Mercury,” said Boeing’s Vice-President and Program Manager of Commercial Crew Programs John Elbon. “The purpose of this transportation system is just to take passengers to the space station, so our design is focused on that mission.”

Boeing had not only a mock up, but a structural test article of the CST-100 on display as well. Photo Credit: Jason Rhian

The numerous capsules on display as well as other “Space-Taxi” systems such as the one proposed by Sierra Nevada highlight efforts to shrink the human space flight gap that will start on July 21, when Atlantis conducts its final wheel stop. With the number of spacecraft that have flown, are being tested or just now emerging off the drawing boards it is possible that the U.S. might have a variety of craft for a wide range of missions. For now however, NASA will have to rely on Russia’s Soyuz Spacecraft.

Posted on by David Gonzales

Bringing You There: Atlantis Roars into Orbit One Final Time

Videographers David Gonzales, Kurt Johnson and Mike Deep filmed the final launch of the Space Shuttle from the Kennedy Space Center Press Site.  The team used multiple cameras along with a high definition stereo audio recording device to capture the sights and sounds as Atlantis thundered into orbit. The goal was to provide the closest launch experience for the viewer without actually being there.

A Space Shuttle launch is a spectacle that will never again be seen.  The sequence begins with a tight shot of the pad in the final seconds of the count.  As the 3 Space Shuttle Main Engines ignite they flash water from the sound suppression water system into steam, sending a plume billowing away.   The entire stack rocks a couple of feet before settling back vertical. The Solid Rocket boosters ignite, launching out a second plume and lifting the 4.5 million pound stack off the ground. Spectators erupt into cheers and the shutters of thousands of press cameras click away.

Continue reading “Bringing You There: Atlantis Roars into Orbit One Final Time”

Posted on by Nancy Atkinson

Where In The Universe Challenge #150

It’s time for another Where In The Universe Challenge! Name where in the Universe this image was taken and give yourself extra points if you can name the telescope or spacecraft responsible for the image. Post your guesses in the comments section, and check back on later at this same post to find the answer. To make this challenge fun for everyone, please don’t include links or extensive explanations with your answer. Good luck!

And you can now find the answer to the previous WITU Challenge back at the original post.

UPDATE: The answer is now posted below!

This image was taken by the Hubble Space Telescope in December 2004, and it provides a detailed look at the tattered remains of a supernova explosion known as Cassiopeia A (Cas A). It is the youngest known remnant from a supernova explosion in the Milky Way. The image is a composite made from 18 separate images using Hubble’s Advanced Camera for Surveys (ACS). See this link on the HubbleSite for more info.

Posted on by Tammy Plotner

Turning On A Supermassive Black Hole

A new study combining data from ESO’s Very Large Telescope and ESA’s XMM-Newton X-ray space observatory has turned up a surprise. Most of the huge black holes in the centres of galaxies in the past 11 billion years were not turned on by mergers between galaxies, as had been previously thought. Credit: CFHT/IAP/Terapix/CNRS/ESO

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ESO’s Very Large Telescope and ESA’s XMM-Newton X-ray Space Observatory has just opened our eyes once again. While we thought that the massive black holes that lurk at the center of large galaxies (and they always lurk, don’t they? they never just lay about, lallygag, or loiter…) for the last 11 billion years were turned on by mergers, we’re finding out it just might not be so.

For all astronomers, we’re aware that galactic structure involves a mostly quiescent central black hole. But as we reach further out into the Universe, we’re finding that early, brighter galaxies have a middle monster – one which appears to be noshing on a material that emits intense radiation. So if a galaxy merger isn’t responsible, then where does the material originate to ignite a quiet black hole into an active galactic nucleus? Maybe the omni-present dark matter…

Viola Allevato (Max-Planck-Institut für Plasmaphysik; Excellence Cluster Universe, Garching, Germany) and an international team of scientists from the COSMOS collaboration have studied 600 active galaxies in an intensively mapped region called the COSMOS field. Spanning an area consisting of about five degrees of celestial real estate in the constellation of Sextans, the COSMOS field has been richly observed by multiple telescopes at multiple wavelengths. This gives astronomers a great “picture” from which to draw data.

What they found was pretty much what they had expected – most of the active galaxies in the past 11 billion years were only moderately bright. But what they weren’t prepared to understand is why the majority of these more common, less bright active galaxies weren’t triggered by mergers. It’s a problematic situation that had previously been tackled by the Hubble Space Telescope, but COSMOS is looking back even further in time and with greater detail – a three-dimensional map showing where the active galaxies reside. “It took more than five years, but we were able to provide one of the largest and most complete inventories of active galaxies in the X-ray sky,” said Marcella Brusa, one of the authors of the study.

These new charts could help further our understanding of distribution as the universe aged and further refine modeling techniques. The new information also points to active galactic nuclei being hosted in large galaxies with abundances of dark matter… against popular theory. “These new results give us a new insight into how supermassive black holes start their meals,” said Viola Allevato, who is lead author on the new paper. “They indicate that black holes are usually fed by processes within the galaxy itself, such as disc instabilities and starbursts, as opposed to galaxy collisions.”

Alexis Finoguenov, who supervised the work, concludes: “Even in the distant past, up to almost 11 billion years ago, galaxy collisions can only account for a small percentage of the moderately bright active galaxies. At that time galaxies were closer together so mergers were expected to be more frequent than in the more recent past, so the new results are all the more surprising.”

Original News Source: ESO Press Release.