Looking Back to the Cradle of Our Universe

NASA's Spitzer and Hubble Space Telescopes have spotted what might be one of the most distant galaxies known, harkening back to a time when our universe was only about 650 million years old (our universe is 13.8 billion years old). The galaxy, known as Abell2744 Y1, is about 30 times smaller than our Milky Way galaxy and is producing about 10 times more stars, as is typical for galaxies in our young universe.

The discovery comes from the Frontier Fields program, which is pushing the limits of how far back we can see into the distant universe using NASA's multi-wavelength suite of Great Observatories. Spitzer sees infrared light, Hubble sees visible and shorter-wavelength infrared light, and NASA's Chandra X-ray Observatory sees X-rays. The telescopes are getting a boost from natural lenses: they peer through clusters of galaxies, where gravity magnifies the light of more distant galaxies.

The Frontier Fields program will image six galaxy clusters in total. Hubble images of the region are used to spot candidate distant galaxies, and then Spitzer is needed to determine if the galaxies are, in fact, as far as they seem. Spitzer data also help determine how many stars are in the galaxy.

These early results from the program come from images of the Abell 2744 galaxy cluster. The distance to this galaxy, if confirmed, would make it one of the farthest known. Astronomers say it has a redshift of 8, which is a measure of the degree to which its light has been shifted to redder wavelengths due to the expansion of our universe. The farther a galaxy, the higher the redshift. The farthest confirmed galaxy has a redshift of more than 7. Other candidates have been identified with redshifts as high as 11.

"Just a handful of galaxies at these great distances are known," said Jason Surace, of NASA's Spitzer Science Center at the California Institute of Technology, Pasadena. "The Frontier Fields program is already working to find more of these distant, faint galaxies. This is a preview of what's to come."

The findings, led by astronomers from the Instituto de Astrofísica de Canarias and La Laguna University, are accepted for publication in the scientific journal Astronomy and Astrophysics Letters.

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NASA Released January Solar Flare Images

The sun emitted a mid-level solar flare, peaking at 5:13 a.m. EST on Jan. 7, 2014. Images of the flare were captured by NASA's Solar Dynamics Observatory and showed that it came from an active region on the sun that currently sports one of the largest sunspots seen in the last 10 years. Sunspots are regions of strong and complex magnetic fields on the sun's surface.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an M7.2-class flare.

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NASA's Hubble Space Telescope Finds Dead Stars 'Polluted with Planet Debris

NASA's Hubble Space Telescope has found the building blocks for Earth-sized planets in an unlikely place-- the atmospheres of a pair of burned-out stars called white dwarfs.

These dead stars are located 150 light-years from Earth in a relatively young star cluster, Hyades, in the constellation Taurus. The star cluster is only 625 million years old. The white dwarfs are being polluted by asteroid-like debris falling onto them.

Hubble's Cosmic Origins Spectrograph observed silicon and only low levels of carbon in the white dwarfs' atmospheres. Silicon is a major ingredient of the rocky material that constitutes Earth and other solid planets in our solar system. Carbon, which helps determine properties and origin of planetary debris, generally is depleted or absent in rocky, Earth-like material.

"We have identified chemical evidence for the building blocks of rocky planets," said Jay Farihi of the University of Cambridge in England. He is lead author of a new study appearing in the Monthly Notices of the Royal Astronomical Society. "When these stars were born, they built planets, and there's a good chance they currently retain some of them. The material we are seeing is evidence of this. The debris is at least as rocky as the most primitive terrestrial bodies in our solar system."

This discovery suggests rocky planet assembly is common around stars, and it offers insight into what will happen in our own solar system when our sun burns out 5 billion years from now.

Farihi's research suggests asteroids less than 100 miles (160 kilometers) wide probably were torn apart by the white dwarfs' strong gravitational forces. Asteroids are thought to consist of the same materials that form terrestrial planets, and seeing evidence of asteroids points to the possibility of Earth-sized planets in the same system.

The pulverized material may have been pulled into a ring around the stars and eventually funneled onto the dead stars. The silicon may have come from asteroids that were shredded by the white dwarfs' gravity when they veered too close to the dead stars.

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Mars-Bound Instrument Detects Solar Burst's Effects

The largest solar particle event since 2005 has been detected by the radiation-monitoring instrument aboard the Mars Science Laboratory spacecraft, on its way from Earth to Mars.

The Radiation Assessment Detector, inside the mission's Curiosity rover tucked inside the spacecraft, is measuring the radiation exposure that could affect a human astronaut on a potential Mars mission. It has measured an increase resulting from a Jan. 22 solar storm observed by other NASA spacecraft. No harmful effects to the Mars Science Laboratory have been detected from this solar event.

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NASA's Dawn's Spacecraft Views Dark Side of Vesta

Dawn took this image over Vesta's northern hemisphere after the spacecraft completed its first passage over the dark side of the giant asteroid. It is northern hemisphere winter on Vesta now, so its north pole is in deep shadow.

The Dawn science team is working to determine the significance of the distinct features in this image, which include large grooves or ridges extending for great distances around Vesta.

This image was taken by Dawn's framing camera on July 23, from a distance of 3,200 miles (5,200 kilometers).

The Dawn mission to Vesta and Ceres is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, for NASA. The University of California, Los Angeles, is responsible for overall Dawn mission science. The Dawn framing cameras have been developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The Framing Camera project is funded by the Max Planck Society, DLR, and NASA/JPL.

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STEREO Sees Complete Far Side

The far side unveiled! This is the first complete image of the solar far side, the half of the sun invisible from Earth. Captured on June 1, 2011, the composite image was assembled from NASA's two Solar TErrestrial RElations Observatory (STEREO) spacecraft. STEREO-Ahead's data is shown on the left half of image and STEREO-Behind's data on the right.

The STEREO spacecraft reached opposition (180° separation) on February 6 but part of the sun was inaccessible to their combined view until June 1. This image represents the first day when the entire far side could be seen.

The image is aligned so that solar north is directly up. The seam between the two images is inclined because the plane of Earth’s -- and STEREO's -- orbit, known as the "ecliptic", is inclined with respect to the sun's axis of rotation. The data was collected by STEREO's Extreme Ultraviolet Imagers in the SECCHI instrument suites.

STEREO was built and is operated for NASA by the Applied Physical Laboratory of the Johns Hopkins University; the spacecraft were launched on October 25, 2006 aboard a Delta II. The SECCHI instrument suite is a collaboration led by the Naval Research Laboratory, and the EUVI instruments were built by the Lockheed Martin Solar and Astrophysics Laboratory.

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NASA's Hubble Finds Rare 'Blue Straggler' Stars in Milky Way's Hub

NASA's Hubble Space Telescope has found a rare class of oddball stars called blue stragglers in the hub of our Milky Way, the first detected within our galaxy's bulge.

Blue stragglers are so named because they seemingly lag behind in the aging process, appearing younger than the population from which they formed. While they have been detected in many distant star clusters, and among nearby stars, they never have been seen inside the core of our galaxy.

It is not clear how blue stragglers form. A common theory is that they emerge from binary pairs. As the more massive star evolves and expands, the smaller star gains material from its companion. This stirs up hydrogen fuel and causes the growing star to undergo nuclear fusion at a faster rate. It burns hotter and bluer, like a massive young star.

The findings support the idea that the Milky Way's central bulge stopped making stars billions of years ago. It now is home to aging sun-like stars and cooler red dwarfs. Giant blue stars that once lived there have long since exploded as supernovae.

The results have been accepted for publication in an upcoming issue of The Astrophysical Journal. Lead author Will Clarkson of Indiana University in Bloomington, will discuss them today at the American Astronomical Society meeting in Boston.

"Although the Milky Way bulge is by far the closest galaxy bulge, several key aspects of its formation and subsequent evolution remain poorly understood," Clarkson said. "Many details of its star-formation history remain controversial. The extent of the blue straggler population detected provides two new constraints for models of the star-formation history of the bulge."

The discovery followed a seven-day survey in 2006 called the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS). Hubble peered at 180,000 stars in the crowded central bulge of our galaxy, 26,000 light-years away. The survey was intended to find hot Jupiter-class planets that orbit very close to their stars. In doing so, the SWEEPS team also uncovered 42 oddball blue stars with brightness and temperatures typical for stars much younger than ordinary bulge stars.

The observations clearly indicate that if there is a young star population in the bulge, it is very small. It was not detected in the SWEEPS program. Blue stragglers long have been suspected to be living in the bulge, but had not been observed because younger stars in the disk of our galaxy lie along the line-of-sight to the core, confusing and contaminating the view.

Astronomers used Hubble to distinguish the motion of the core population from foreground stars in the Milky Way. Bulge stars orbit the galactic center at a different speed than foreground stars. Plotting their motion required returning to the SWEEPS target region with Hubble two years after the first observations were made. The blue stragglers were identified as moving along with the other stars in the bulge.

"The size of the field of view on the sky is roughly that of the thickness of a human fingernail held at arm's length, and within this region, Hubble sees about a quarter million stars toward the bulge," Clarkson said. "Only the superb image quality and stability of Hubble allowed us to make this measurement in such a crowded field."

From the 42 candidate blue stragglers, the investigators estimate 18 to 37 are likely genuine. The remainder could be a mix of foreground objects and, at most, a small population of genuinely young bulge stars.

"The SWEEPS program was designed to detect transiting planets through small light variations" said Kailash Sahu, the principal investigator of the SWEEPS program. "Therefore the program could easily detect the variability of binary pairs, which was crucial in confirming these are indeed blue stragglers."

Hubble is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Md., manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington.

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NASA Shows Topography of Tsunami-Damaged Japan City

The topography surrounding Sendai, Japan is clearly visible in this combined radar image and topographic view generated with data from NASA's Shuttle Radar Topography Mission (SRTM) acquired in 2000. On March 11, 2011, a magnitude 8.9 earthquake struck offshore about 130 kilometers (80 miles) east of Sendai, the capital city of Japan's Miyagi Prefecture, generating a tsunami that devastated the low-lying coastal city of about 1 million residents.

The city is centered in the image and lies along the coastal plain between the Ohu Mountains and the Pacific Ocean. The eastern part of the city is a low-lying plains area, while the city center is hilly (the city's official elevation is about 43 meters, or 141 feet). Sendai's western areas are mountainous, with its highest point being Mt. Funagata at an elevation of about 1,500 meters (4,921 feet) above sea level.

According to the U.S. Geological Survey, the earthquake occurred as a result of thrust faulting on or near the subduction zone interface plate boundary between the Pacific and North America plates. At the latitude of this earthquake, the Pacific plate moves approximately westwards with respect to the North America plate at a velocity of 83 millimeters (3.3 inches) per year. The Pacific plate thrusts underneath Japan at the Japan Trench, and dips to the west beneath Eurasia. The location, depth and focal mechanism of the March 11 earthquake are consistent with the event having occurred as thrust faulting associated with subduction along this plate boundary.

This image combines a radar image acquired in February 2000 during the SRTM mission, and color-coding by topographic height using data from the same mission. Dark green colors indicate low elevations, rising through yellow and tan, to white at the highest elevations.

The Shuttle Radar Topography Mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C.

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Monster Prominence Erupts from the Sun

When a rather large M 3.6 class flare occurred near the edge of the Sun on Feb. 24, 2011, it blew out a gorgeous, waving mass of erupting plasma that swirled and twisted for 90 minutes. NASA’s Solar Dynamics Observatory captured the event in extreme ultraviolet light. Because SDO images are high definition, the team was able to zoom in on the flare and still see exquisite details. And using a cadence of a frame taken every 24 seconds, the sense of motion is, by all appearances, seamless.

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