NASA News - NASA's Spitzer Sees the Light of Alien "Super Earth"
emanating from a "super-Earth" planet beyond our solar system for the
first time. While the planet is not habitable, the detection is a
historic step toward the eventual search for signs of life on other planets.
"Spitzer has amazed us yet again," said Bill Danchi, Spitzer program
scientist at NASA Headquarters in Washington. "The spacecraft is
pioneering the study of atmospheres of distant planets and paving the
way for NASA's upcoming James Webb Space Telescope to apply a similar
technique on potentially habitable planets."
The planet, called 55 Cancri e, falls into a class of planets termed
super Earths, which are more massive than our home world but lighter
than giant planets like Neptune. Fifty-five Cancri e is about twice
as big and eight times as massive as Earth. The planet orbits a
bright star, called 55 Cancri, in a mere 18 hours.
Previously, Spitzer and other telescopes were able to study the planet
by analyzing how the light from 55 Cancri changed as the planet
passed in front of the star. In the new study, Spitzer measured how
much infrared light comes from the planet itself. The results reveal
the planet is likely dark and its sun-facing side is more than 2,000
Kelvin (3,140 degrees Fahrenheit), hot enough to melt metal.
The new information is consistent with a prior theory that 55 Cancri e
is a water world: a rocky core surrounded by a layer of water in a
"supercritical" state where it is both liquid and gas, and topped by
a blanket of steam.
"It could be very similar to Neptune, if you pulled Neptune in toward
our sun and watched its atmosphere boil away," said Michaël Gillon of
Université de Liège in Belgium, principal investigator of the
research, which appears in the Astrophysical Journal. The lead author
is Brice-Olivier Demory of the Massachusetts Institute of Technology
in Cambridge.
The 55 Cancri system is relatively close to Earth at 41 light-years
away. It has five planets, with 55 Cancri e being the closest to the
star and tidally locked, so one side always faces the star. Spitzer
discovered the sun-facing side is extremely hot, indicating the
planet probably does not have a substantial atmosphere to carry the
sun's heat to the unlit side.
NASA's James Webb Space Telescope, scheduled to launch in 2018, likely
will be able to learn even more about the planet's composition. The
telescope might be able to use a similar infrared method as Spitzer
to search other potentially habitable planets for signs of molecules
possibly related to life.
"When we conceived of Spitzer more than 40 years ago, exoplanets
hadn't even been discovered," said Michael Werner, Spitzer project
scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena,
Calif. "Because Spitzer was built very well, it's been able to adapt
to this new field and make historic advances such as this."
In 2005, Spitzer became the first telescope to detect light from a
planet beyond our solar system. To the surprise of many, the
observatory saw the infrared light of a "hot Jupiter," a gaseous
planet much larger than the solid 55 Cancri e. Since then, other
telescopes, including NASA's Hubble and Kepler space telescopes, have
performed similar feats with gas giants using the same method.
In this method, a telescope gazes at a star as a planet circles behind
it. When the planet disappears from view, the light from the star
system dips ever so slightly, but enough that astronomers can
determine how much light came from the planet itself. This
information reveals the temperature of a planet, and, in some cases,
its atmospheric components. Most other current planet-hunting methods
obtain indirect measurements of a planet by observing its effects on the star.
During Spitzer's ongoing extended mission, steps were taken to enhance
its unique ability to see exoplanets, including 55 Cancri e. Those
steps, which included changing the cycling of a heater and using an
instrument in a new way, led to improvements in how precisely the
telescope points at targets.
JPL manages the Spitzer Space Telescope mission for NASA's Science
Mission Directorate in Washington. Science operations are conducted
at the Spitzer Science Center at the California Institute of
Technology (Caltech) in Pasadena. Data are archived at the Infrared
Science Archive housed at the Infrared Processing and Analysis Center
at Caltech. Caltech manages JPL for NASA.
For more information about Spitzer, visit:
http://www.nasa.gov/spitzer
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NASA Commercial Partner Spacex Completes Crew Accommodations Milestone
CAPE CANAVERAL, Fla. -- Space Exploration Technologies (SpaceX) hasfinished an important evaluation of a propotype Dragon spacecraft
designed to carry people into orbit. This key milestone is part of
SpaceX's partnership with NASA under a funded Space Act Agreement to
advance the design of crew transportation vehicles.
The primary goal of the tests was to determine whether the layout will
allow astronauts to maneuver effectively in the vehicle. Several
veteran space shuttle astronauts and NASA engineers conducted the
evaluation during a pair of two-day-long reviews.
"I am very pleased with the progress SpaceX and our other commercial
partners are making during the CCDev2 effort," said NASA Commercial
Spaceflight Director Philip McAlister. "Together with NASA's
development of beyond low-Earth orbit systems, commercial crew and
cargo transportation is an integral part of our overall human
spaceflight program."
As part of the Commercial Crew Development Round 2, or CCDev2,
agreement, the company invited the astronauts and engineers to its
headquarters in Hawthorne, Calif., to conduct the evaluation. The
prototype was equipped with seats, lighting, environmental control
and life support systems, conceptual displays and controls, cargo
racks and other interior systems.
"This milestone demonstrated the layout of the crew cabin supports
critical tasks," said SpaceX Commercial Crew Development Manager
Garrett Reisman. "It also demonstrated the Dragon interior has been
designed to maximize the ability of the seven-member crew to do their
job as effectively as possible."
During the reviews, space shuttle veterans Rex Walheim, Tony
Antonelli, Eric Boe and Tim Kopra participated in so-called "human
factor assessments." This included entering and exiting Dragon under
normal and emergency scenarios. They also performed reach and
visibility evaluations.
"As an anchor customer for commercial transportation services, we are
happy to provide SpaceX with knowledge and lessons learned from our
50 years of human spaceflight," said Commercial Crew Program Manager
Ed Mango. "We appreciate the opportunity SpaceX gave us to provide
feedback on these critical interior systems while the company
maintains its flexibility to appeal to other customers."
This is the seventh of 10 milestones SpaceX must meet under the CCDev2
agreement, which continues through July 31. This includes the
development of a launch abort system for crew escape during launch or ascent.
All of NASA's industry partners continue to meet their established
milestones in developing safe, reliable and affordable commercial
crew transportation capabilities.
For more information about NASA's Commercial Crew Program, visit:
http://www.nasa.gov/
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