Friday, October 29, 2010

Dark Reflections in the Southern Cross

NASA's Wide-field Infrared Survey Explorer, or WISE, captured this colorful image of the reflection nebula IRAS 12116-6001. This cloud of interstellar dust cannot be seen directly in visible light, but WISE's detectors observed the nebula at infrared wavelengths.

In images of reflection nebulae taken with visible light, clouds of dust reflect the light of nearby stars. The dust is warmed to relatively cool temperatures by the starlight and glows with infrared light, which WISE can detect. Reflection nebulae are of interest to astronomers because they are often the sites of new star formation.

The bright blue star on the right side of the image is the variable star Epsilon Crucis. In the Bayer system of stellar nomenclature, stars are given names based on their relative brightness within a constellation. The Greek alphabet is used to designate the star's apparent brightness compared to other stars in the same constellation. "Alpha" is the brightest star in the constellation, "beta" the second brightest, and so on. In this case, "epsilon" is the fifth letter of the Greek alphabet, so Epsilon Crucis is the fifth brightest star in the constellation Crux.

Crux is a well-known constellation that can be easily seen by observers in the Southern Hemisphere and from low northern latitudes. Also known as the Southern Cross, Crux is featured in many country's flags, including Australia, Brazil and New Zealand (although New Zealand's flag does not include Epsilon Crucis).

The colors used in this image represent specific wavelengths of infrared light. The blue color of Epsilon Crucis represents light emitted at 3.4 and 4.6 microns. The green-colored star seen beside Epsilon Crucis is emitting light at 12 microns. This star is IRAS 12194-6007, a carbon star that is near the end of its lifecycle. Since the infrared wavelengths emitted by this star are longer than those from Epsilon Crucis, it is cooler. The green and red colors seen in the reflection nebula represent 12- and 22-micron light coming from the nebula's dust grains warmed by nearby stars.

Friday, October 22, 2010

New Cometary Phenomenon Greets Approaching Spacecraft

Recent observations of comet Hartley 2 have scientists scratching their heads, while they anticipate a flyby of the small, icy world on Nov. 4.

A phenomenon was recorded by imagers aboard NASA's Deep Impact spacecraft from Sept. 9 to 17 during pre-planned scientific observations of the comet. These observations, when coupled with expected images during the closest encounter with Hartley 2 on Nov. 4, will become the most detailed look yet at a comet's activity during its pass through the inner-solar system.

"On Earth, cyanide is known as a deadly gas. In space it's known as one of the most easily observed ingredients that is always present in a comet," said Mike A'Hearn of the University of Maryland, College Park. A'Hearn is principal of EPOXI, an extended mission that utilizes the already "in flight" Deep Impact spacecraft. "Our observations indicate that cyanide released by the comet increased by a factor of five over an eight-day period in September without any increase in dust emissions," A'Hearn said. "We have never seen this kind of activity in a comet before, and it could affect the quality of observations made by astronomers on the ground."

The new phenomenon is very unlike typical cometary outbursts, which have sudden onsets and are usually accompanied by considerable dust. It also seems unrelated to the cyanide jets that are sometimes seen in comets. The EPOXI science team believes that astronomers and interested observers viewing the comet from Earth should be aware of this type of activity when planning observations and interpreting their data.

"If observers monitoring Hartley 2 do not take into account this new phenomenon, they could easily get the wrong picture of how the comet is changing as it approaches and recedes from the sun," said A'Hearn.

Cyanide is a carbon-based molecule. It is believed that billions of years ago, a bombardment of comets carried cyanide and other building blocks of life to Earth.

The name EPOXI itself is a combination of the names for the two extended mission components: the extrasolar planet observations, called Extrasolar Planet Observations and Characterization (EPOCh), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (DIXI). The spacecraft will continue to be referred to as "Deep Impact."

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the EPOXI mission for NASA's Science Mission Directorate, Washington. The University of Maryland, College Park, is home to the mission's principal investigator, Michael A'Hearn. Drake Deming of NASA's Goddard Space Flight Center, Greenbelt, Md., is the science lead for the mission's extrasolar planet observations. The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.

For more information about EPOXI visit

Tuesday, October 19, 2010

Taking On Water Resource Issues

Worldwide today, it is estimated that nearly 1.1 billion people live without access to adequate water supplies and about 2.6 billion people lack adequate water sanitation. Improved understanding of water processes at global and regional scales is essential for sustainability.

Researchers at JPL recently launched the Western Water Resource Solutions website to highlight activities that apply NASA expertise and data to water resource issues in the western United States.

One focus area for this new site is the hydrologic cycle and using global satellite observations of the Earth to improve our understanding of water processes on a regional and local level. The western United States is expected to bear the brunt of impacts to water resource availability because of changing precipitation patterns, increasing temperatures, and a growing population. California is already starting to feel the impacts and is taking action to develop new adaptive management practices to ensure a safe and reliable water supply, while maintaining healthy ecosystems throughout the state.

NASA researchers at Ames Research Center, the Jet Propulsion Laboratory, and Marshall Space Flight Center are currently working with water managers to apply NASA expertise and data to water resource issues in California. The project partners with universities, agencies and other stakeholders, to utilize information from a number of sources, including existing ground observations and models.

This project is only one of several NASA initiatives aimed at providing actionable scientific information on water quality and the water balance worldwide. These other projects include development of better estimates of snow pack, groundwater monitoring, soil moisture and evapotranspiration, water quality, and monitoring fragile levee systems.

In addition to raising awareness about current water resource challenges, the new website highlights NASA’s capability to use satellite and airborne data to help solve some of these challenges.

Learn more about the Western Water Resource Solution Group at:

Friday, October 15, 2010

NASA Study of Haiti Quake Yields Surprising Results

The magnitude 7.0 earthquake that caused more than 200,000 casualties and devastated Haiti's economy in January resulted not from the Enriquillo fault, as previously believed, but from slip on multiple faults -- primarily a previously unknown, subsurface fault -- according to a study published online this week in Nature Geoscience.

In addition, because the earthquake did not involve slip near Earth's surface, the study suggests that it did not release all of the strain that has built up on faults in the area over the past two centuries, meaning that future surface-rupturing earthquakes in this region are likely.

Geophysicist Eric Fielding of NASA's Jet Propulsion Laboratory, Pasadena, Calif., along with lead author Gavin Hayes of the U.S. Geological Survey and other colleagues from USGS, the California Institute of Technology in Pasadena, the University of Texas at Austin, and Nagoya University, Japan, used a combination of seismological observations, geologic field data and satellite geodetic measurements to analyze the earthquake source. Initially the Haiti earthquake was thought to be the consequence of movement along a single fault -- the Enriquillo -- that accommodates the motion between the Caribbean and North American tectonic plates. But scientists in the field found no evidence of surface rupture on that fault.

The researchers found the pattern of surface deformation was dominated by movement on a previously unknown, subsurface thrust fault, named the Léogâne fault, which did not rupture the surface.

Fielding, who processed synthetic aperture radar interferometry data from a Japan Aerospace Exploration Agency (JAXA) satellite used in the study, said, "I was surprised when I saw the satellite data showed the Haiti earthquake must have ruptured a different fault than the major Enriquillo fault, which everybody expected was the source. Without the radar images, we might still be wondering what happened."

Fielding said NASA images acquired after the earthquake over the major fault zones of Hispaniola by the JPL-built Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) airborne instrument will give scientists much more detailed information should another large earthquake occur in the region in the future.

For more information, read the USGS news release: .
To read the full study, visit: .

For more on UAVSAR, see: .

STS-133 Crew Begins Dress Rehearsal

At NASA's Kennedy Space Center in Florida, STS-133 Commander Steve Lindsey speaks to the media gathered at the Shuttle Landing Facility. From left are Nicole Stott, Michael Barratt, Eric Boe, Tim Kopra and Alvin Drew. The crew is gathered for a practice launch dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) in preparation for the upcoming mission. TCDT provides each shuttle crew and launch team with an opportunity to participate in various simulated countdown activities, including equipment familiarization and emergency training. Space shuttle Discovery and its STS-133 crew will deliver the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the International Space Station. Launch is targeted for Nov. 1 at 4:40 p.m.

Monday, October 11, 2010

Mobile Mars Lab Almost Ready for Curiosity Rover

The Sample Analysis at Mars (SAM) instrument suite has completed assembly at NASA's Goddard Space Flight Center in Greenbelt, Md., and is nearly ready for a December delivery to NASA's Jet Propulsion Laboratory, Pasadena, Calif., where it will be installed into the Curiosity rover.

The Mars Science Laboratory mission will use SAM and other instruments on Curiosity to examine whether an intriguing area of Mars has had environmental conditions favorable for microbial life and favorable for preserving evidence of life, if it existed. Launch is scheduled for late 2011, with landing in August 2012.

SAM will explore molecular and elemental chemistry relevant to life. It will analyze samples of Martian rock and soil to assess carbon chemistry through a search for organic compounds, and to look for clues about planetary change.

SAM is in flight configuration, meaning its instruments are in the condition they will be in during launch and are ready to begin operations on Mars. The instrument suite (a mass spectrometer, gas chromatograph and tunable laser spectrometer) started final environmental testing this week, which includes vibration and thermal testing to ensure SAM can survive the launch, deep space flight and conditions on Mars.

Wednesday, October 06, 2010

Spiral Extraordinaire

Scientists have yet to discover what caused the strange spiral structure. Nor do they know why it glows. The glow may be caused by light reflected from nearby stars. As for the spiral itself, current supposition is that this is the result of a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected. Given the expansion rate of the spiral gas, a new layer must appear about every 800 years, a close match to the time it takes for the two stars to orbit each other. The above image was taken in near-infrared light by the Hubble Space Telescope.