Commemorating Challenger

NASA marks 25th anniversary of Challenger accident

June Scobee Rodgers, left, widow of Dick Scobee, commander of space shuttle Challenger, and William Gerstenmaier, NASA Associate Administrator for Space Operations, place a wreath at the Space Mirror Memorial at a remembrance ceremony to mark the 25th Anniversary of space shuttle Challenger at the Kennedy Space Center visitor complex in Cape Canaveral, Fla., Friday, Jan. 28, 2011. On the memorial, top left, are the names of the astronauts that perished in Challenger. (AP Photo/John Raoux)

CAPE CANAVERAL, Fla. – Hundreds gathered at NASA's launch site Friday to mark the 25th anniversary of the Challenger disaster, receiving words of hope from the widow of the space shuttle's commander.

The chilly outdoor ceremony drew space agency managers, former astronauts, past and present launch directors, family and friends of the fallen crew — and schoolchildren who weren't yet born when the space shuttle carrying a high school teacher from Concord, N.H., erupted in the sky.

The accident on Jan. 28, 1986 — just 73 seconds into flight — killed all seven on board, including schoolteacher Christa McAuliffe. story-->>

NASA Research Team Reveals Moon Has Earth-Like Core]

Jan. 6, 2011

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown@nasa.gov

Janet Anderson
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034
janet.l.anderson@nasa.gov
RELEASE: 11-004

NASA RESEARCH TEAM REVEALS MOON HAS EARTH-LIKE CORE

WASHINGTON - State-of-the-art seismological techniques applied to
Apollo-era data suggest our moon has a core similar to Earth's.

Uncovering details about the lunar core is critical for developing
accurate models of the moon's formation. The data sheds light on the
evolution of a lunar dynamo -- a natural process by which our moon
may have generated and maintained its own strong magnetic field.

The team's findings suggest the moon possesses a solid, iron-rich
inner core with a radius of nearly 150 miles and a fluid, primarily
liquid-iron outer core with a radius of roughly 205 miles. Where it
differs from Earth is a partially molten boundary layer around the
core estimated to have a radius of nearly 300 miles. The research
indicates the core contains a small percentage of light elements such
as sulfur, echoing new seismology research on Earth that suggests the
presence of light elements -- such as sulfur and oxygen -- in a layer
around our own core.

The researchers used extensive data gathered during the Apollo-era
moon missions. The Apollo Passive Seismic Experiment consisted of
four seismometers deployed between 1969 and 1972, which recorded
continuous lunar seismic activity until late-1977.

"We applied tried and true methodologies from terrestrial seismology
to this legacy data set to present the first-ever direct detection of
the moon's core," said Renee Weber, lead researcher and space
scientist at NASA's Marshall Space Flight Center in Huntsville, Ala.

In addition to Weber, the team consisted of scientists from Marshall;
Arizona State University; the University of California at Santa Cruz;
and the Institut de Physique du Globe de Paris in France. Their
findings are published in the online edition of the journal Science.

The team also analyzed Apollo lunar seismograms using array
processing, techniques that identify and distinguish signal sources
of moonquakes and other seismic activity. The researchers identified
how and where seismic waves passed through or were reflected by
elements of the moon's interior, signifying the composition and state
of layer interfaces at varying depths.

Although sophisticated satellite imaging missions to the moon made
significant contributions to the study of its history and topography,
the deep interior of Earth's sole natural satellite remained a
subject of speculation and conjecture since the Apollo era.
Researchers previously had inferred the existence of a core, based on
indirect estimates of the moon's interior properties, but many
disagreed about its radius, state and composition.

A primary limitation to past lunar seismic studies was the wash of
"noise" caused by overlapping signals bouncing repeatedly off
structures in the moon's fractionated crust. To mitigate this
challenge, Weber and the team employed an approach called seismogram
stacking, or the digital partitioning of signals. Stacking improved
the signal-to-noise ratio and enabled the researchers to more clearly
track the path and behavior of each unique signal as it passed
through the lunar interior.

"We hope to continue working with the Apollo seismic data to further
refine our estimates of core properties and characterize lunar
signals as clearly as possible to aid in the interpretation of data
returned from future missions," Weber said.

Future NASA missions will help gather more detailed data. The Gravity
Recovery and Interior Laboratory, or GRAIL, is a NASA Discovery-class
mission set to launch this year. The mission consists of twin
spacecraft that will enter tandem orbits around the moon for several
months to measure the gravity field in unprecedented detail. The
mission also will answer longstanding questions about Earth's moon
and provide scientists a better understanding of the satellite from
crust to core, revealing subsurface structures and, indirectly, its
thermal history.

NASA and other space agencies have been studying concepts to establish
an International Lunar Network -- a robotic set of geophysical
monitoring stations on the moon -- as part of efforts to coordinate
international missions during the coming decade.

For more information about NASA science exploration missions, visit:

http://www.nasa.gov/topics/moonmars

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NASA's Kepler Mission Discovers Its First Rocky Planet]

Jan. 10, 2011

Trent J. Perrotto
Headquarters, Washington
202-358-0321
trent.j.perrotto@nasa.gov

Rachel Hoover
Ames Research Center, Moffett Field, Calif.
650-604-0643
rachel.hoover@nasa.gov

RELEASE: 11-007

NASA'S KEPLER MISSION DISCOVERS ITS FIRST ROCKY PLANET

WASHINGTON -- NASA's Kepler mission confirmed the discovery of its
first rocky planet, named Kepler-10b. Measuring 1.4 times the size of
Earth, it is the smallest planet ever discovered outside our solar
system.

The discovery of this so-called exoplanet is based on more than eight
months of data collected by the spacecraft from May 2009 to early
January 2010.

"All of Kepler's best capabilities have converged to yield the first
solid evidence of a rocky planet orbiting a star other than our sun,"
said Natalie Batalha, Kepler's deputy science team lead at NASA's
Ames Research Center in Moffett Field, Calif., and primary author of
a paper on the discovery accepted by the Astrophysical Journal. "The
Kepler team made a commitment in 2010 about finding the telltale
signatures of small planets in the data, and it's beginning to pay
off."

Kepler's ultra-precise photometer measures the tiny decrease in a
star's brightness that occurs when a planet crosses in front of it.
The size of the planet can be derived from these periodic dips in
brightness. The distance between the planet and the star is
calculated by measuring the time between successive dips as the
planet orbits the star.

Kepler is the first NASA mission capable of finding Earth-size planets
in or near the habitable zone, the region in a planetary system where
liquid water can exist on the planet's surface. However, since it
orbits once every 0.84 days, Kepler-10b is more than 20 times closer
to its star than Mercury is to our sun and not in the habitable zone.

Kepler-10 was the first star identified that could potentially harbor
a small transiting planet, placing it at the top of the list for
ground-based observations with the W.M. Keck Observatory 10-meter
telescope in Hawaii.

Scientists waiting for a signal to confirm Kepler-10b as a planet were
not disappointed. Keck was able to measure tiny changes in the star's
spectrum, called Doppler shifts, caused by the telltale tug exerted
by the orbiting planet on the star.

"The discovery of Kepler 10-b is a significant milestone in the search
for planets similar to our own," said Douglas Hudgins, Kepler program
scientist at NASA Headquarters in Washington. "Although this planet
is not in the habitable zone, the exciting find showcases the kinds
of discoveries made possible by the mission and the promise of many
more to come," he said.

Knowledge of the planet is only as good as the knowledge of the star
it orbits. Because Kepler-10 is one of the brighter stars being
targeted by Kepler, scientists were able to detect high frequency
variations in the star's brightness generated by stellar
oscillations, or starquakes. This analysis allowed scientists to pin
down Kepler-10b's properties.

There is a clear signal in the data arising from light waves that
travel within the interior of the star. Kepler Asteroseismic Science
Consortium scientists use the information to better understand the
star, just as earthquakes are used to learn about Earth's interior
structure. As a result of this analysis, Kepler-10 is one of the most
well characterized planet-hosting stars in the universe.

That's good news for the team studying Kepler-10b. Accurate stellar
properties yield accurate planet properties. In the case of
Kepler-10b, the picture that emerges is of a rocky planet with a mass
4.6 times that of Earth and with an average density of 8.8 grams per
cubic centimeter -- similar to that of an iron dumbbell.

Ames manages Kepler's ground system development, mission operations
and science data analysis. NASA's Jet Propulsion Laboratory in
Pasadena, Calif., managed Kepler mission development.

Ball Aerospace and Technologies Corp. in Boulder, Colo., developed the
Kepler flight system and supports mission operations with the
Laboratory for Atmospheric and Space Physics at the University of
Colorado in Boulder. The Space Telescope Science Institute in
Baltimore archives, hosts and distributes the Kepler science data.

Kepler is NASA's 10th Discovery Mission and is funded by NASA's
Science Mission Directorate at the agency's headquarters. For more
information about the Kepler mission, visit:

http://www.nasa.gov/kepler

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NASA'S Fermi Catches Thunderstorms Hurling Antimatter Into Space]

Jan. 10, 2011

Trent Perrotto
Headquarters, Washington
202-358-0321
trent.j.perrotto@nasa.gov

Janet Anderson
Marshall Space Flight Center, Huntsville, Ala.
256-544-6162
janet.l.anderson@nasa.gov

RELEASE: 11-008

NASA'S FERMI CATCHES THUNDERSTORMS HURLING ANTIMATTER INTO SPACE

WASHINGTON -- Scientists using NASA's Fermi Gamma-ray Space Telescope
have detected beams of antimatter produced above thunderstorms on
Earth, a phenomenon never seen before.

Scientists think the antimatter particles were formed in a terrestrial
gamma-ray flash (TGF), a brief burst produced inside thunderstorms
and shown to be associated with lightning. It is estimated that about
500 TGFs occur daily worldwide, but most go undetected.

"These signals are the first direct evidence that thunderstorms make
antimatter particle beams," said Michael Briggs, a member of Fermi's
Gamma-ray Burst Monitor (GBM) team at the University of Alabama in
Huntsville (UAH). He presented the findings Monday, during a news
briefing at the American Astronomical Society meeting in Seattle.

Fermi is designed to monitor gamma rays, the highest energy form of
light. When antimatter striking Fermi collides with a particle of
normal matter, both particles immediately are annihilated and
transformed into gamma rays. The GBM has detected gamma rays with
energies of 511,000 electron volts, a signal indicating an electron
has met its antimatter counterpart, a positron.

Although Fermi's GBM is designed to observe high-energy events in the
universe, it's also providing valuable insights into this strange
phenomenon. The GBM constantly monitors the entire celestial sky
above and the Earth below. The GBM team has identified 130 TGFs since
Fermi's launch in 2008.

"In orbit for less than three years, the Fermi mission has proven to
be an amazing tool to probe the universe. Now we learn that it can
discover mysteries much, much closer to home," said Ilana Harrus,
Fermi program scientist at NASA Headquarters in Washington.

The spacecraft was located immediately above a thunderstorm for most
of the observed TGFs, but in four cases, storms were far from Fermi.
In addition, lightning-generated radio signals detected by a global
monitoring network indicated the only lightning at the time was
hundreds or more miles away. During one TGF, which occurred on Dec.
14, 2009, Fermi was located over Egypt. But the active storm was in
Zambia, some 2,800 miles to the south. The distant storm was below
Fermi's horizon, so any gamma rays it produced could not have been
detected.

"Even though Fermi couldn't see the storm, the spacecraft nevertheless
was magnetically connected to it," said Joseph Dwyer at the Florida
Institute of Technology in Melbourne, Fla. "The TGF produced
high-speed electrons and positrons, which then rode up Earth's
magnetic field to strike the spacecraft."

The beam continued past Fermi, reached a location, known as a mirror
point, where its motion was reversed, and then hit the spacecraft a
second time just 23 milliseconds later. Each time, positrons in the
beam collided with electrons in the spacecraft. The particles
annihilated each other, emitting gamma rays detected by Fermi's GBM.

Scientists long have suspected TGFs arise from the strong electric
fields near the tops of thunderstorms. Under the right conditions,
they say, the field becomes strong enough that it drives an upward
avalanche of electrons. Reaching speeds nearly as fast as light, the
high-energy electrons give off gamma rays when they're deflected by
air molecules. Normally, these gamma rays are detected as a TGF.

But the cascading electrons produce so many gamma rays that they blast
electrons and positrons clear out of the atmosphere. This happens
when the gamma-ray energy transforms into a pair of particles: an
electron and a positron. It's these particles that reach Fermi's
orbit.

The detection of positrons shows many high-energy particles are being
ejected from the atmosphere. In fact, scientists now think that all
TGFs emit electron/positron beams. A paper on the findings has been
accepted for publication in Geophysical Research Letters.

"The Fermi results put us a step closer to understanding how TGFs
work," said Steven Cummer at Duke University. "We still have to
figure out what is special about these storms and the precise role
lightning plays in the process."

NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle
physics partnership. It is managed by NASA's Goddard Space Flight
Center in Greenbelt, Md. It was developed in collaboration with the
U.S. Department of Energy, with important contributions from academic
institutions and partners in France, Germany, Italy, Japan, Sweden
and the United States.

The GBM Instrument Operations Center is located at the National Space
Science Technology Center in Huntsville, Ala. The team includes a
collaboration of scientists from UAH, NASA's Marshall Space Flight
Center in Huntsville, the Max Planck Institute for Extraterrestrial
Physics in Germany and other institutions.

For more Fermi information, images and animations, visit:

http://www.nasa.gov/fermi

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