Posted on by Jason Major

Curiosity’s Laser Leaves Its Mark

Before-and-after images from Curiosity’s ChemCam  micro-imager show holes left by its million-watt laser (NASA/JPL-Caltech/LANL/CNES/IRAP/LPGN/CNRS)

PEWPEWPEWPEWPEW! Curiosity’s head-mounted ChemCam did a little target practice on August 25, blasting millimeter-sized holes in a soil sample named “Beechey” in order to acquire spectrographic data from the resulting plasma glow. The neat line of holes is called a five-by-one raster, and was made from a distance of about 11.5 feet (3.5 meters).

Sorry Obi-Wan, but Curiosity’s blaster is neither clumsy nor random!

Mounted to Curiosity’s “head”, just above its Mastcam camera “eyes”, ChemCam combines a powerful laser with a telescope and spectrometer that can analyze the light emitted by zapped materials, thereby determining with unprecedented precision what Mars is really made of.

Read: Take a Look Through Curiosity’s ChemCam

For five billionths of a second the laser focuses a million watts of energy onto a specific point. Each of the 5 holes seen on Beechey are the result of 50 laser hits. 2 to 4 millimeters in diameter, the holes are much larger than the laser point itself, which is only .43 millimeters wide at that distance.

ChemCam’s laser allows Curiosity to zap and examine targets up to 23 feet (7 meters) away. Credit: J-L. Lacour/CEA/French Space Agency (CNES)

“ChemCam is designed to look for lighter elements such as carbon, nitrogen, and oxygen, all of which are crucial for life,” said Roger Wiens, principal investigator of the ChemCam team. “The system can provide immediate, unambiguous detection of water from frost or other sources on the surface as well as carbon – a basic building block of life as well as a possible byproduct of life. This makes the ChemCam a vital component of Curiosity’s mission.”

Visit the official ChemCam site for more information.

Posted on by John Williams

Changing Hues Signal Transition of Seasons at Saturn

The giant moon Titan passes in front of Saturn in this natural-color, wide-angle view from NASA’s Cassini spacecraft. Image Credit: NASA/JPL-Caltech/SSI

[SPOILER ALERT: Viewing these images will force you to change your computer wallpaper]

Here on Earth, it’s almost time for the burst of fall color that signals the change of seasons in the Northern Hemisphere. Saturn’s color too is transforming subtly as the gas giant slips into a Saturnian spring and autumn as seen in this series of true-color images from NASA’s Cassini spacecraft.

Titan, a moon larger than the planet Mercury, hangs before the rings and changing colors of Saturn in the first of four spectacular images release by NASA and the Cassini Imaging Central Laboratory for Operations (CICLOPS).

“For no other reason than that they are gorgeous, the Cassini imaging team is releasing today a set of fabulous images of Saturn and Titan…in living color…for your day-dreaming enjoyment,” said Carolyn Porco, Cassini imaging team lead based at the Space Science Institute in Boulder, Colordo, in an email blast.

When Cassini arrived at Saturn eight years ago, the planet’s northern hemisphere, locked in winter, showed azure blue. Now as winter passes to the southern hemisphere, the colors are reversing as the blue fades from the north and rises in the south.

“Note that our presence at Saturn for the last eight years has made possible the sighting of subtle changes with time, and one such change is obvious here,” Porco said. “As the seasons have advanced, and spring has come to the north and autumn to the south throughout the Saturn system, the azure blue in the northern winter Saturnian hemisphere that greeted Cassini upon its arrival in 2004 is now fading; and it is now the southern hemisphere, in its approach to winter, that is taking on a bluish hue.”

Scientists believe that the increasing blue color in the south likely is due to the increasing intensity of ultraviolet light from the Sun which produces the haze. Methane in the atmosphere also absorbs light toward the red end of the spectrum while reflecting blue light. This view looks from just above the ring plane with the Sun shining from above casting broad shadows on the colorful clouds of Saturn. The image was taken on May 6, 2012 from about 778,000 kilometers (483,000 miles) from Titan.

Some of the views, including this image of a vortex at Titan’s south pole are only possible because of a newly tilted, or inclined, orbit that takes Cassini high over the poles of Saturn and its moons. Scientists first noticed the detached mass of clouds over the south pole in March. The swirling mass of the vortex stands out clearly against the golden cloud deck surrounding Titan.

The recently formed south polar vortex stands out against Titan in this natural-color view from NASA’s Cassini spacecraft. Image Credit: NASA/JPL-Caltech/SSI

Sunlight scattering through Titan’s atmosphere forms a ring of color as NASA’s Cassini spacecraft cruises along the night side of Saturn’s largest moon. Image Credit: NASA/JPL-Caltech/SSI

A glowing hint of the polar vortex shows in this image looking toward the night-time, Saturn-facing side of Titan. Sunlight scattering through Titan’s atmosphere forms the ring of color in this image taken about 216,000 kilometers (134,000 miles) from Titan.

Saturn’s rings cut colorful Titan in half in this image from NASA’s Cassini spacecraft. Image Credit: NASA/JPL-Caltech/SSI

The rings obscure Titan in the final image of the quartet. The image is taken from just above the northern, sunlit side of the ring plane. Saturn’s shadow cast along the rings create the dark swath in the center of the image but if you look close, you can see a tiny sliver of Titan through the Cassini Division, the largest gap in Saturn’s wide rings.

“Cassini has been in orbit now for the last eight years, and despite the fact that we can’t know exactly what the next five years will show us, we can be certain that whatever it is will be wondrous,” said Porco.

About the author: John Williams is owner of TerraZoom, a Colorado-based web development shop specializing in web mapping and online image zooms. He also writes the award-winning blog, StarryCritters, an interactive site devoted to looking at images from NASA’s Great Observatories and other sources in a different way. A former contributing editor for Final Frontier, his work has appeared in the Planetary Society Blog, Air & Space Smithsonian, Astronomy, Earth, MX Developer’s Journal, The Kansas City Star and many other newspapers and magazines.

Posted on by Jason Major

What Has the Kuiper Belt Taught Us About The Solar System?

Over 4 billion miles (6.7 billion km) from the Sun, the Kuiper Belt is a vast zone of frozen worlds we still know very little about. Image: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)

Today marks the 20th anniversary of the discovery of the first Kuiper Belt Object, 1992QB1. KBOs are distant and mostly tiny worlds made up of ice and rock that orbit the Sun at incredible distances, yet are still very much members of our Solar System. Since 1992 over 1,300 KBOs have been found, and with NASA’s New Horizons spacecraft speeding along to its July 2015 rendezvous with Pluto and Charon (which one could argue are technically the first KBOs ever found) and then onwards into the Belt, we will soon know much more about these far-flung denizens of deep space.

But how has the discovery of the Kuiper Belt — first proposed by Gerard Kuiper in 1951 (and in a fashion even earlier by Kenneth Edgeworth) — impacted our current understanding of the Solar System? New Horizons Principal Investigator Alan Stern from the Southwest Research Institute recently discussed this on his mission blog, “The PI’s Perspective.”

First, Stern lists some of the surprisingly diverse physical aspects of KBOs that have been discovered so far:

  • Some are red and some are gray;
  • The surfaces of some are covered in water ice, but others (like Pluto) have exotic volatile ices like methane and nitrogen;
  • Many have moons, though none with more known moons than Pluto;
  • Some are highly reflective (like Pluto), others have much darker surfaces;
  • Some have much lower densities than Pluto, meaning they are primarily made of ice. Pluto’s density is so high that we know its interior is about 70% rock in its interior; a few known KBOs are more dense than Pluto, and even rockier!

But although these features are fascinating in themselves, just begging for further exploration, Stern notes that there are three very important lessons that the Kuiper Belt has taught us about the Solar System:

1. Our planetary system is much larger than we had ever thought.

“In fact, we were largely unaware of the Kuiper Belt — the largest structure in our solar system — until it was discovered 20 years ago,”  Stern writes. “It’s akin to not having maps of the Earth that included the Pacific Ocean as recently as 1992!”

2. Planetary locations and orbits can change over time.

“This even creates whole flocks of migration of planets in some cases. We have firm evidence that many KBOs (including some large ones like Pluto), were born much closer to the Sun, in the region where the giant planets now orbit.”

3. Our solar system, and likely others as well, was very good at making small planets.

“Today we know of more than a dozen dwarf planets in the solar system, and those dwarfs already outnumber the number of gas giants and terrestrial planets combined. But it is estimated that the ultimate number of dwarf planets we will discover in the Kuiper Belt and beyond may well exceed 10,000. Who knew?”

And with a little jab at the whole Pluto-isn’t-a-planet topic, Stern asks: “And which class of planet is the misfit now?”

Read: Was Pluto Ever REALLY a Planet?

The discovery of the Kuiper Belt has shown us that our solar system — and very likely planetary systems across the galaxy, even the Universe — aren’t neat and tidy things that can be easily summed up with grade-school models or chalkboard diagrams. Instead they are incredibly diverse and dynamic, continually evolving and consisting of countless, varied worlds spanning enormous distances… yet still connected through the ever-present effects of gravity (not to mention the occasional-yet-unavoidable collision.)

“What an amazing set of paradigm shifts in our knowledge the Kuiper Belt has brought so far. Our quaint 1990s and earlier view of the solar system missed its largest structure!”

– Alan Stern, New Horizons Principal Investigator

Read more about the New Horizons mission here.

 The first KBO identified, 1992 QB1 (European Southern Observatory)

Posted on by Nancy Atkinson

NASA Launches Twin Probes to Study Earth’s Radiation Belts

After nearly a week of weather and technical delays, NASA’s Radiation Belt Storm Probes (RBSP) launched in the early morning skies from the Cape Canaveral Air Force Station in Florida at 4:05a.m. EDT (08:05 GMT) on Thursday, August 30, 2012. This will be the first twin-spacecraft mission designed to explore our planet’s radiation belts.

“Scientists will learn in unprecedented detail how the radiation belts are populated with charged particles, what causes them to change and how these processes affect the upper reaches of the atmosphere around Earth,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate at Headquarters in Washington. “The information collected from these probes will benefit the public by allowing us to better protect our satellites and understand how space weather affects communications and technology on Earth.”

The two satellites, launched from an Atlas V rocket from Space Launch Complex-41, each weigh just under 680 kg (1,500 pounds) and comprise the first dual-spacecraft mission specifically created to investigate this hazardous regions of near-Earth space, known as the radiation belts. These two belts, named for their discoverer, James Van Allen, encircle the planet like donuts and are filled with highly charged particles. The belts are affected by solar storms and coronal mass ejections and sometimes swell dramatically. When this occurs, they can pose dangers to communications, GPS satellites and human spaceflight

Artist’s conception of RBSP satellite. Image courtesy of Johns Hopkins University Applied Physics Laboratory

“We have never before sent such comprehensive and high-quality instruments to study high radiation regions of space,” said Barry Mauk, RBSP project scientist at the Johns Hopkins University’s Applied Physics Laboratory (APL) in Laurel, Md. “RBSP was crafted to help us learn more about, and ultimately predict, the response of the radiation belts to solar inputs.”

The hardy RBSP satellites will spend the next 2 years looping through every part of both Van Allen belts. By having two spacecraft in different regions of the belts at the same time, scientists finally will be able to gather data from within the belts themselves, learning how they change over space and time. Designers fortified RBSP with special protective plating and rugged electronics to operate and survive within this punishing region of space that other spacecraft avoid. In addition, a space weather broadcast will transmit selected data from those instruments around the clock, giving researchers a check on current conditions near Earth.

“The excitement of seeing the spacecraft in orbit and beginning to perform science measurements is like no other thrill,” said Richard Fitzgerald, RBSP project manager at APL. “The entire RBSP team, from across every organization, worked together to produce an amazing pair of spacecraft.”

The first RBSP spacecraft separated from the Atlas rocket’s Centaur booster 1 hour, 18 minutes, 52 seconds after launch. The second RBSP spacecraft followed 12 minutes, 14 seconds later.

During the next 60 days, operators will power up all flight systems and science instruments and deploy long antenna booms, two of which are more than 54 yards long. Data about the particles that swirl through the belts, and the fields and waves that transport them, will be gathered by five instrument suites designed and operated by teams at the New Jersey Institute of Technology in Newark; the University of Iowa in Iowa City; University of Minnesota in Minneapolis; and the University of New Hampshire in Durham; and the National Reconnaissance Office in Chantilly, Va. The data will be analyzed by scientists across the nation almost immediately.

Posted on by Ken Kremer

Mars Trek begins for Curiosity

Image Caption: Martian Soil caked on Curiosity’s right middle and rear wheels after Sol 22 Drive. Credit: NASA/JPL-Caltech

Mars Trek has begun for NASA’s Curiosity rover. The mega rover has departed from her touchdown vicinity at “Bradbury Landing” and set off on a multi-week eastwards traverse to her first science target which the team has dubbed “Glenelg”

Glenelg lies about a quarter mile (400 meters) away and the car-sized rover drove about 52 feet (16 meters) on Tuesday, Aug 28 or Sol 22 of the mission.

The science team selected Glenelg as the first target for detailed investigation because it sits at the intersection of three types of geologic terrain, affording the researchers the chance to get a much more comprehensive look at the diversity of geology inside the Gale Crater landing site.

The Sol 22 drive was the third overall for Curiosity and the farthest so far. At this new location, some 33 feet ( 10 m) from Bradbury Landing , the Mastcam color camera is collecting high resolution images to create a 3 D map of features off in the distance that will aid the rover drivers in planning a safe traverse route.

“This drive really begins our journey toward the first major driving destination, Glenelg, and it’s nice to see some Martian soil on our wheels,” said mission manager Arthur Amador of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The drive went beautifully, just as our rover planners designed it.”

In about a week, the science team plans to deploy the 7 ft (2.1 meter) long robotic arm and test the science instruments in the turret positioned at the terminus of the arm.

“We are on our way, though Glenelg is still many weeks away,” said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. “We plan to stop for just a day at the location we just reached, but in the next week or so we will make a longer stop.”

Perhaps in about a year or so, Curiosity will reach the base of Mount Sharp, her ultimate destination, and begin climbing up the side of the 3.6 mile (5.5 km) high mound in search of hydrated minerals that will shed light on the duration of Mars watery past.

The goal is to determine if Mars ever had habitats capable of supporting microbial life in the past or present during the 2 year long primary mission phase. Curiosity is equipped with a sophisticated array of 10 state of the art science instruments far beyond any prior rover.

Ken Kremer

Image Caption: Curiosity Points to her ultimate drive destination – Mount Sharp – with unstowed robotic arm on Aug. 20. This navigation camera (Navcam) mosaic was assembled from images on multiple Sols. Curiosity will search for hydrated minerals using the robotic arm and a neutron detector on the body. Image stitching and processing by Ken Kremer and Marco Di Lorenzo. Featured at APOD on 27 Aug 2012. Credit: NASA/JPL-Caltech/Ken Kremer/Marco Di Lorenzo

Posted on by Nancy Atkinson

Hot Dog! WISE Finds a Bounty of Black Holes

From a NASA press release:

NASA’s Wide-field Infrared Survey Explorer (WISE) mission has led to a bonanza of newfound supermassive black holes and extreme galaxies called hot DOGs, or dust-obscured galaxies.

Images from the telescope have revealed millions of dusty black hole candidates across the universe and about 1,000 even dustier objects thought to be among the brightest galaxies ever found. These powerful galaxies, which burn brightly with infrared light, are nicknamed hot DOGs.

“WISE has exposed a menagerie of hidden objects,” said Hashima Hasan, WISE program scientist at NASA Headquarters in Washington. “We’ve found an asteroid dancing ahead of Earth in its orbit, the coldest star-like orbs known and now, supermassive black holes and galaxies hiding behind cloaks of dust.”

WISE scanned the whole sky twice in infrared light, completing its survey in early 2011. Like night-vision goggles probing the dark, the telescope captured millions of images of the sky. All the data from the mission have been released publicly, allowing astronomers to dig in and make new discoveries.

The latest findings are helping astronomers better understand how galaxies and the behemoth black holes at their centers grow and evolve together. For example, the giant black hole at the center of our Milky Way galaxy, called Sagittarius A*, has 4 million times the mass of our sun and has gone through periodic feeding frenzies where material falls towards the black hole, heats up and irradiates its surroundings. Bigger central black holes, up to a billion times the mass of our sun, may even shut down star formation in galaxies.

In one study, astronomers used WISE to identify about 2.5 million actively feeding supermassive black holes across the full sky, stretching back to distances more than 10 billion light-years away. About two-thirds of these objects never had been detected before because dust blocks their visible light. WISE easily sees these monsters because their powerful, accreting black holes warm the dust, causing it to glow in infrared light.

This zoomed-in view of a portion of the all-sky survey from WISE shows a collection of quasar candidates. Image credit: NASA/JPL-Caltech/UCLA

“We’ve got the black holes cornered,” said Daniel Stern of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., lead author of the WISE black hole study and project scientist for another NASA black-hole mission, the Nuclear Spectroscopic Telescope Array (NuSTAR). “WISE is finding them across the full sky, while NuSTAR is giving us an entirely new look at their high-energy X-ray light and learning what makes them tick.”

In two other WISE papers, researchers report finding what are among the brightest galaxies known, one of the main goals of the mission. So far, they have identified about 1,000 candidates.

These extreme objects can pour out more than 100 trillion times as much light as our sun. They are so dusty, however, that they appear only in the longest wavelengths of infrared light captured by WISE. NASA’s Spitzer Space Telescope followed up on the discoveries in more detail and helped show that, in addition to hosting supermassive black holes feverishly snacking on gas and dust, these DOGs are busy churning out new stars.

“These dusty, cataclysmically forming galaxies are so rare WISE had to scan the entire sky to find them,” said Peter Eisenhardt, lead author of the paper on the first of these bright, dusty galaxies, and project scientist for WISE at JPL. “We are also seeing evidence that these record setters may have formed their black holes before the bulk of their stars. The ‘eggs’ may have come before the ‘chickens.'”

More than 100 of these objects, located about 10 billion light-years away, have been confirmed using the W.M. Keck Observatory on Mauna Kea, Hawaii, as well as the Gemini Observatory in Chile, Palomar’s 200-inch Hale telescope near San Diego, and the Multiple Mirror Telescope Observatory near Tucson, Ariz.

The WISE observations, combined with data at even longer infrared wavelengths from Caltech’s Submillimeter Observatory atop Mauna Kea, revealed that these extreme galaxies are more than twice as hot as other infrared-bright galaxies. One theory is their dust is being heated by an extremely powerful burst of activity from the supermassive black hole.

“We may be seeing a new, rare phase in the evolution of galaxies,” said Jingwen Wu of JPL, lead author of the study on the submillimeter observations. All three papers are being published in the Astrophysical Journal.

The three technical journal articles, including PDFs, can be found at http://arxiv.org/abs/1205.0811, http://arxiv.org/abs/1208.5517 and http://arxiv.org/abs/1208.5518 .

Lead image caption: With its all-sky infrared survey, NASA’s Wide-field Infrared Survey Explorer, or WISE, has identified millions of quasar candidates. Image credit: NASA/JPL-Caltech/UCLA

Posted on by Tammy Plotner

Let’s Send Neil Back To The Moon

As a native-born and life-long resident of Ohio, I have lived in the shadow of Neil Armstrong all my life. I visit Wapokenta every few years for two simple reasons – I love the Armstrong Museum and I feel a need to pass that heritage on to children, grandchildren and visiting friends. Of course, I was crushed when I read of his death. I would have given anything to have had Armstrong’s autograph on my original Apollo landing newspapers, or even just to have seen the man. He was a humble hero… and this is the quality that I loved most about him. However, Neil Armstrong and his quiet ways didn’t just impact my life. He touched us all.

“Early on Sunday morning here in Australia I got the news I never wanted to hear.” says Dave Reneke of Australia. “I was in the middle of a radio interview on a local station when they cut in with the news that Neil Armstrong had passed away. “What?? What are you telling me…Neil’s dead!!” I cut the interview short because I simply couldn’t go on.

Neil Armstrong wasn’t just an American hero; he belonged to the entire world. Kids wanted to be like him. Men looked up to him and every woman wanted to be Mrs. Neil Armstrong. My world had just collapsed and I didn’t know what to do.

A humble man who, as a kid, only ever wanted to fly, Neil went on to pilot the famous X-15 rocket plane, fly dozens of dangerous missions during the Korean War and later travel in space with Dave Scott on the Gemini 8 mission in 1966. He was unknowingly paving the way for his ultimate destiny to be the first man to walk on the Moon a mere 3 years later.

There will never be another event like this. If anything epitomises the twentieth century it was the first Moon landing. Our first steps on another world. Those of us who witnessed it remember where they were at the time, just as we did when Elvis died and Kennedy was assassinated. Tragedy imprints, indelibly!

For 12 hours during and throughout that moon walk period there was virtually no crime around the world. One in six human beings were watching the moon landing on TV, even the crims, and listening on radios. For a moment in time we were united – we knew, we just knew we were witnessing one of the greatest events in history unfold right before our very eyes.

You only get one shot at this. Only one person can walk on the moon for the first time. It took guts – the ‘right stuff!’ Neil gave them a 50/50 chance of getting to the Moon and getting back. Nasa’s odds were about the same. They were both 38 years old with families and a whole lifetime in front of them, but they went.

I was lucky enough to be invited to spend the morning with Buzz Aldrin at his home in California in 2008, prior to writing a story about the upcoming 40th anniversary of Apollo 11. I remember asking Buzz what concerned them the most, what was the one thing they were concerned about and feared the most.

Both he and Neil had two days cooped up in a small capsule to think about that. He paused, looked up and surprised me by saying they were very aware they were being watched. “We knew that everything we did and everything we said was being recorded for future history,” Buzz said. “It was on our minds constantly.”

OK, it’s over. Neil Armstrong’s name will live on from this day forward. He’s gone beyond the term legend. In the annals of history he’ll be seen as a giant, the Wilbur Wright of our time. Hundreds of years from now kids in a future classroom will be learning about Neil Armstrong, as we studied ancient history in our day.

But hang on, do we leave it all here? Is this where the story ends? Let’s do something about it, something quite radical but completely sensible. Let’s send Neil Armstrong back to the Moon! Not literally but posthumously. Let’s start a movement that will reverberate back to NASA, to the white house and engage a lobby group to have Neil Armstrong’s ashes interred on the Moon.

I’m proposing a monument to be built on the Sea Of Tranquillity, on the spot where Neil and Buzz walked and, if there’s no national burial planned, place his ashes there. An eternal symbol and testament to human accomplishment – as Neil put it, the place where men from planet Earth first set foot on the Moon, and came in peace for all mankind.

Let it be slated for the first Moon return mission, by any country or private consortium. A stone minimally inscribed with a simple message telling the story for future generations. The blood, sweat, tears and spirit of countless thousands who worked on the Moon missions would be indelibly imprinted on it. Even the words ‘Neil and Buzz were here’ would satisfy me.

We’ve got the ‘Monument to a Century of Flight’ located at the Aycock Brown Welcome Centre at milepost 1.5 in Kitty Hawk, NC, the Smithsonian cradles flight history and the ashes of people like Gene Rodenberry, James Doohan et al circle the earth in tributary gestures.

Neil’s remains would be in good company on the Moon sharing the eternal silence with the ashes of Eugene Shoemaker. If you just asked “who” Google the name, it’s a great story. Folks, this is not something we need to do, it’s something we should do!”

The author of this narrative would like to hear any feedback, especially if you’re in a position to help make this happen. Contact Dave Reneke, writer and publicist for Australasian Science magazine via his webpage www.davidreneke.com or email [email protected]

Posted on by Jason Major

Effects of Einstein’s Elusive Gravitational Waves Observed

Chandra data (above, graph) on J0806 show that its X-rays vary with a period of 321.5 seconds, or slightly more than five minutes. This implies that the X-ray source is a binary star system where two white dwarf stars are orbiting each other (above, illustration) only 50,000 miles apart, making it one of the smallest known binary orbits in the Galaxy. According to Einstein's General Theory of Relativity, such a system should produce gravitational waves - ripples in space-time - that carry energy away from the system and cause the stars to move closer together. X-ray and optical observations indicate that the orbital period of this system is decreasing by 1.2 milliseconds every year, which means that the stars are moving closer at a rate of 2 feet per year.
Potential stellar collision. Credit: Chandra

Two white dwarfs similar to those in the system SDSS J065133.338+284423.37 spiral together in this illustration from NASA. Credit: D. Berry/NASA GSFC

Locked in a spiraling orbital embrace, the super-dense remains of two dead stars are giving astronomers the evidence needed to confirm one of Einstein’s predictions about the Universe.

A binary system located about 3,000 light-years away, SDSS J065133.338+284423.37 (J0651 for short) contains two white dwarfs orbiting each other rapidly — once every 12.75 minutes. The system was discovered in April 2011, and since then astronomers have had their eyes — and four separate telescopes in locations around the world — on it to see if gravitational effects first predicted by Einstein could be seen.

According to Einstein, space-time is a structure in itself, in which all cosmic objects — planets, stars, galaxies — reside. Every object with mass puts a “dent” in this structure in all dimensions; the more massive an object, the “deeper” the dent. Light energy travels in a straight line, but when it encounters these dents it can dip in and veer off-course, an effect we see from Earth as gravitational lensing.

Einstein also predicted that exceptionally massive, rapidly rotating objects — such as a white dwarf binary pair — would create outwardly-expanding ripples in space-time that would ultimately “steal” kinetic energy from the objects themselves. These gravitational waves would be very subtle, yet in theory, observable.

Read: Astronomy Without a Telescope: Gravitational Waves

What researchers led by a team at The University of Texas at Austin have found is optical evidence of gravitational waves slowing down the stars in J0651. Originally observed in 2011 eclipsing each other (as seen from Earth) once every six minutes, the stars now eclipse six seconds sooner. This equates to a predicted orbital period reduction of about 0.25 milliseconds each year.*

“These compact stars are orbiting each other so closely that we have been able to observe the usually negligible influence of gravitational waves using a relatively simple camera on a 75-year-old telescope in just 13 months,” said study lead author J.J. Hermes, a graduate student at The University of Texas at Austin.

Based on these measurements, by April 2013 the stars will be eclipsing each other 20 seconds sooner than first observed. Eventually they will merge together entirely.

Although this isn’t “direct” observation of gravitational waves, it is evidence inferred by their predicted effects… akin to watching a floating lantern in a dark pond at night moving up and down and deducing that there are waves present.

“It’s exciting to confirm predictions Einstein made nearly a century ago by watching two stars bobbing in the wake caused by their sheer mass,” said Hermes.

As of early last year NASA and ESA had a proposed mission called LISA (Laser Interferometer Space Antenna) that would have put a series of 3 detectors into space 5 million km apart, connected by lasers. This arrangement of precision-positioned spacecraft could have detected any passing gravitational waves in the local space-time neighborhood, making direct observation possible. Sadly this mission was canceled due to FY2012 budget cuts for NASA, but ESA is moving ahead with developments for its own gravitational wave mission, called eLISA/NGO — the first “pathfinder” portion of which is slated to launch in 2014.

The study was submitted to Astrophysical Journal Letters on August 24. Read more on the McDonald Observatory news release here.

Inset image: simulation of binary black holes causing gravitational waves – C. Reisswig, L. Rezzolla (AEI); Scientific visualization – M. Koppitz (AEI & Zuse Institute Berlin)

*The difference in the eclipse time is noted as six seconds even though the orbital period decay of the two stars is only .25 milliseconds/year because of a pile-up effect of all the eclipses observed since April 2011. The measurements made by the research team takes into consideration the phase change in the J0651 system, which experiences a piling effect — similar to an out-of-sync watch — that increases relative to time^2 and is therefore a larger and easier number to detect and work with. Once that was measured, the actual orbital period decay could be figured out.

Posted on by Nancy Atkinson

Satellites Keep Track of Hurricane Isaac

This visible image of Tropical Storm Isaac taken from NOAA’s GOES-13 satellite shows the huge extent of the storm, where the eastern-most clouds lie over the Carolinas and the western-most clouds are brushing east Texas. The image was captured on Tuesday, Aug. 28, 2012 at 10:25 a.m. EDT. Image Credit: NASA GOES Project

As expected Tropical Storm Isaac has now become a full-fledged hurricane, after being fed by the warm waters in the Gulf of Mexico. The slow moving storm is now closing in on the Louisiana-Mississippi coast and could make landfall in the region seven years to the day after Hurricane Katrina devastated the same area. It is not expected to be another Katrina, but with the slowness of the storm — about 16 km/h (10 mph) — forecasters are predicting 7-14 inches of rainfall across the coast as well as inland regions, and some places could even see 20 inches. Flooding from rainfall and storm surges are expected, according to NOAA. Satellites have been keeping an eye on the storm, and above is an image from one of the GOES satellites taken on Tuesday, August 28. Below are more satellite views.

The Proba-2 satellite’s X-Cam – Exploration Camera – acquired this image at 11:38:33 GMT on August 27, 2012. Credit: ESA

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image of Isaac over the Gulf of Mexico at 2:00 p.m. CDT on August 27, 2012. Credit: NASA

Here’s a screenshot of Weather.com’s Hurricane Tracker for Isaac. Click here to see up-to-the-minute details on Isaac.

Sources: NOAA, NASA, ESA

Posted on by Jason Major

Curiosity Sends Back Incredible Hi-Res Views of Mt. Sharp

Wow — what a view! This image, released today, is a high-resolution shot of the Curiosity rover’s ultimate goal: the stratified flanks of Gale Crater’s 3.4-mile (5.5-km) high central peak, Mount Sharp. The image was taken with Curiosity’s 100mm telephoto Mastcam as a calibration test… if views like this are what we can expect from the MSL mission, all I can say is (and I’ve said it before) GO CURIOSITY!


“This is an area on Mount Sharp where Curiosity will go,” said Mastcam principal investigator Michael Malin of Malin Space Science Systems. “Those layers are our ultimate objective. The dark dune field is between us and those layers. In front of the dark sand you see redder sand, with a different composition suggested by its different color. The rocks in the foreground show diversity — some rounded, some angular, with different histories. This is a very rich geological site to look at and eventually to drive through.”

Read more: Take a Trip to Explore Gale Crater

The gravel-strewn region in the foreground is Curiosity’s immediate landing area. Then the ground dips into a low depression called a swale, then rises up again to the edge of a crater that’s rimmed with larger rocks. Quite a bit beyond that (about 2.2 miles/3.7 km away) are fields of dunes composed of darker material, and then the hummocky base of Mount Sharp itself begins to rise up about 3.4 miles (5.5 km) in the distance.

The topmost ridges of Mount Sharp visible above are actually 10 miles (16.2 km) away.

A crop of the full-size image shows a large rock at the foot of a knoll that’s about the same size as Curiosity (which is this big compared to a person and previous rovers):

The rocky mound just behind the boulder in that image is itself about 1,000 feet (300 meters) across and 300 feet (100 meters) high. Gale Crater isn’t a place for a faint-hearted rover!

The colors have been modified from the original image in order to help better discern landforms and differences in surface materials. Here, the images look more like what we’d see under natural Earthly lighting.

Curiosity already is returning more data from the Martian surface than have all of NASA’s earlier rovers combined.

“We have an international network of telecommunications relay orbiters bringing data back from Curiosity,” said JPL’s Chad Edwards, chief telecommunications engineer for NASA’s Mars Exploration Program. “Curiosity is boosting its data return by using a new capability for adjusting its transmission rate.”

See more images from Curiosity here, and keep up to date on the mission at the MSL website here.

“The knowledge we hope to gain from our observation and analysis of Gale Crater will tell us much about the possibility of life on Mars as well as the past and future possibilities for our own planet. Curiosity will bring benefits to Earth and inspire a new generation of scientists and explorers, as it prepares the way for a human mission in the not too distant future.”

– NASA Administrator Charles Bolden in a message transmitted to the Curiosity rover and then back to Earth, August 27, 2012

Images: NASA/JPL-Caltech