Shuttle Endeavour's landing delayed at Cape Canaveral.....

Cape Canaveral, Florida (AFP) March 26, 2008:

 

The space shuttle Endeavour's scheduled landing at Kennedy Space Center was postponed Wednesday due to poor weather after a record-setting mission at the International Space Station, NASA.

However, astronauts were expected to try again at 8:39 pm local time (0039 GMT Thursday) after a brief 90-minute delay, as weather was expected to improve, said flight director Richard Jones.

The Endeavour's mission at the ISS was the longest ever -- 16 days and five spacewalks, the most ever embarked upon in a single mission as astronauts attached a new Japanese laboratory called Kibo to the ISS.

NASA's mission control at Johnson Space Center in Houston, Texas, earlier gave the green light for the shuttle's cargo bay doors to close at 1926 GMT, the first step toward deorbiting.

The delay, announced about two hours later, means deorbiting may not start until 7:33 pm local time (2333 GMT) with landing at Cape Canaveral now scheduled for 8:39 pm (0039 GMT Thursday).

If conditions do not improve, astronauts will try again during several openings Thursday or Friday.

"This has been a two-week adventure and it's been a pleasure and honor to be on it," shuttle co-pilot Greg Johnson told Houston after the crew got their wake-up call from control center around 1500 GMT.

Endeavour commander Dominic Gorie late Sunday described the 16-day mission as an all-around success.

"We've done awesome," Gorie said. "Every spacewalk was a win, every robotic op (operation) was a win."

His comments came after mission specialists Robert Behnken and Mike Foreman attached a 50-foot sensory boom to the outside of the space station.

ISS flight director Dana Weigel said the spacewalk, often referred to by NASA officials as an EVA, or an extra-vehicular activity, had set a new record.

"This was five EVAs ... more than we've done on any station mission," he said.

The spacewalkers also successfully installed an experiment on the outside of the European Space Agency's laboratory, which the astronauts had failed to complete during the third spacewalk on March 17.

Endeavour launched on March 11. Its mission's main tasks were to install the first part of the Japanese Kibo lab, a micro-gravity research facility that will be the station's largest module when completed in March 2009.

Japan Aerospace Exploration Agency astronaut Takao Doi, who is returning on the Endeavour, said Kibo "is going to open up a new era for Japan in the space program."

Astronauts also tested new repair techniques for the shuttle's heat shield. NASA has been testing different in-space repair techniques on the shuttle's protective layer since a crack in Columbia's heat shield caused it to explode while re-entering Earth's atmosphere in 2003, killing its seven-member crew.

Astronauts also assembled the Canadian-made Dextre robot, which is designed to undertake maintenance operations on the space station that until now required a human touch, and reduce the need for risky spacewalks.

The robot's human-like upper torso swivels at the waist, and its arms were designed with seven joints to provide it with maximum versatility. Umbilical connectors provide power and data connectivity.

Manipulated by joysticks inside the ISS or from ground control on Earth, the 1.56-tonne Dextre will conduct operations such as replacing small components on the station's exterior.

NASA wants to complete construction of the ISS by 2010, when its three-shuttle fleet is scheduled to be retired.

Spaceflight Now Hubble servicing mission's launch date threatened

Hubble servicing mission's launch date threatened
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: March 21, 2008

With the shuttle Endeavour's mission entering the home stretch, shuttle Discovery remains on track for blastoff May 25 to ferry a huge Japanese laboratory module to the international space station. But subsequent near-term flights, including a high-profile mission to service the Hubble Space Telescope, could be delayed, sources say, because of ongoing external tank production issues.

The tank used by Endeavour for its current mission was the last in the inventory of tanks built before the 2003 Columbia disaster and subsequently modified to reduce potentially dangerous losses of foam insulation. The tank slated for use with Discovery in late May, ET-128, is the first so-called "in-line" external tank built from the ground up with post-Columbia upgrades, including a new ice-frost ramp design and titanium oxygen line support brackets. Both improvements address areas of possible foam shedding.

ET-128 for Discovery's upcoming mission leaves the Test and Check-out Building near New Orleans this week for the journey to Kennedy Space Center. Credit: Lockheed Martin

ET-128 departed Lockheed Martin's Michoud Assembly Facility in New Orleans Thursday for the 900-mile barge trip to the Kennedy Space Center in Florida.

But a backlog of work at Michoud is hampering downstream tank deliveries. The tank that would be needed for a rescue mission should some mishap strand Discovery's crew in orbit is not expected to reach the Kennedy Space Center until late summer. NASA managers say the space station has enough supplies on board to support a combined crew for more than three months if necessary and as of this writing, Discovery's launch remains on track.

But the picture is cloudier for NASA's next shuttle flight, a mission by the shuttle Atlantis to service the Hubble Space Telescope. Launch currently is targeted for Aug. 28. ET-127, the tank designated as the emergency backup for Discovery's May mission, is the prime tank for the Hubble flight.

Safe haven aboard the space station is not an option for Atlantis' crew if major heat shield damage occurs. The observatory and the station are in different orbits and the shuttle does not have the ability to move from one to the other. As a result, NASA Administrator Mike Griffin early on approved plans to have a second shuttle, Endeavour, ready for launch on a rescue mission just in case.

That means NASA needs two ready-to-fly external tanks for the Hubble mission, ET-127 and ET-129 respectively. Manpower and production issues, triggered in part by unplanned work to upgrade low-level hydrogen fuel sensors and other post-Columbia design upgrades, have slowed external tank manufacturing and sources say the Hubble mission faces a possible delay to October.

Senior program managers visited Michoud for a first-hand look earlier this week and a more realistic assessment of the tank production schedule is expected in the next week or so. For now, the Hubble mission remains officially targeted for launch Aug. 28.

Shuttle Program Manager John Shannon told CBS News Thursday that NASA has "added many new features to further ensure the safety of this tank and since these were the first in-line tanks, we took extra time to make sure we got it right."

"We have margin in the schedule to absorb small delays and we have learned a lot in the process of putting these tanks together so that the '09 and '10 tanks will flow much faster," he said.

Shannon did not address specific launch dates.

NASA plans to complete the space station and retire the shuttle by the end of fiscal 2010. The current manifest calls for four more flights this year - in May, August, October and December - four in 2009 and up to three in 2010.

Endeavour departs the space station and targets a Wednesday landing

       NEWSALERT: Tuesday, March 25, 2008 @ 2015 GMT
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SHUTTLE ENDEAVOUR UNDOCKS FROM THE SPACE STATION
------------------------------------------------
Endeavour departed the international space station Monday evening to close
out a marathon five-spacewalk assembly mission. The astronauts are packing
up the cabin and testing the ship's reentry system for Wednesday's planned
return to Earth.

http://spaceflightnow.com/shuttle/sts123/status.html


STATION CHIEF GIVES DETAILED UPDATE ON JOINT PROBLEM
----------------------------------------------------
Analysis of metallic contamination from a critical solar array rotary
joint on the international space station indicates a "high-friction event"
of some sort, possibly a misaligned bearing roller or some other like
defect, has chewed up and damaged one of the surfaces of a 10-foot-wide
gear and bearing race, the station's program manager said Monday.

http://spaceflightnow.com/shuttle/sts123/080325sarj/


COMPLETE MISSION VIDEO COVERAGE:
http://www.spaceflightnowplus.com/index.php


ODYSSEY GIVES CLUES TO GUIDE SEARCH FOR LIFE ON MARS
----------------------------------------------------
NASA's Mars Odyssey orbiter has found evidence of salt deposits. These
deposits point to places where water once was abundant and where evidence
might exist of possible Martian life from the Red Planet's past.

http://spaceflightnow.com/news/n0803/24marssalt/


SUPER-BRIGHT GAMMA RAY BURST VISIBLE TO NAKED EYE
-------------------------------------------------
An intense stellar explosion - a gamma ray burst - detected by NASA's
Swift space telescope, is the most distant object visible to the naked eye
and the brightest object ever observed by humans.

http://www.astronomynow.com/Super-brightgammarayburst.html


CASSINI FINDS OCEAN MAY EXIST BENEATH TITAN'S CRUST
---------------------------------------------------
NASA's Cassini spacecraft has discovered evidence that points to the
existence of an underground ocean of water and ammonia on Saturn's moon
Titan. The findings, made using radar measurements of Titan's rotation,
appear in the journal Science.

http://spaceflightnow.com/news/n0803/24titan/


SPACEWALKERS ANCHOR INSPECTION BOOM TO STATION
----------------------------------------------
Astronauts Bob Behnken and Mike Foreman went outside for a six-hour
spacewalk Saturday, installing Endeavour's 50-foot-long heat shield
inspection boom on the space station for use by the next shuttle mission,
deploying an experiment package they were unable to attach earlier and
inspecting the station's damaged solar array rotary joint.

http://spaceflightnow.com/shuttle/sts123/080322fd13/


HUBBLE SERVICING MISSION'S LAUNCH DATE THREATENED
-------------------------------------------------
With the shuttle Endeavour's mission entering the home stretch, shuttle
Discovery remains on track for blastoff May 25 to ferry a huge Japanese
laboratory module to the space station. But subsequent near-term flights,
including a high-profile mission to service the Hubble Space Telescope,
could be delayed, sources say, because of ongoing external tank production
issues.

http://spaceflightnow.com/shuttle/sts123/080321tanks/

Craft prepare for next Mars landing / Moon probed by radar

       NEWSALERT: Friday, February 29, 2008 @ 1614 GMT
---------------------------------------------------------------------
           The latest news from Spaceflight Now


+++ NEW SPACE SHUTTLE MISSION DVD'S NOW SHIPPING!
   http://www.spaceflightnowstore.com


SPACECRAFT AT MARS PREPARE FOR NEW KID ON THE BLOCK
---------------------------------------------------
Three Mars spacecraft are adjusting their orbits to be over the right
place at the right time to listen to NASA's Phoenix Mars Lander as it
enters the Martian atmosphere on May 25.

http://spaceflightnow.com/news/n0802/28phoenix/


POTENTIAL LUNAR LANDING SITE EXPLORED BY RADAR
----------------------------------------------
NASA has obtained the highest resolution terrain mapping to date of the
moon's rugged south polar region. Scientists collected the data using the
Deep Space Network's Goldstone Solar System Radar located in California's
Mojave Desert.

http://spaceflightnow.com/news/n0802/28moon/


SCIENTISTS PROBE INTRIGUING PHENOMENON ON ENCELADUS
---------------------------------------------------
An enormous plume of dust and water spurts violently into space from the
south pole of Enceladus, Saturn's sixth-largest moon. This raging eruption
has intrigued scientists ever since the Cassini spacecraft provided
dramatic images of the phenomenon.

http://spaceflightnow.com/news/n0802/27enceladus/


LAKE ERIE CREW DESCRIBES SATELLITE SHOT
---------------------------------------
The crewmembers of the USS Lake Erie were calm as they fired the latest
shot heard round the world. The Aegis-class cruiser fired the missile that
destroyed a dead spy satellite that posed a threat to humans.

http://spaceflightnow.com/news/n0802/28lakeerie/


RIGOROUS TEST COMPLETED FOR FIRST AEHF SATELLITE
------------------------------------------------
Lockheed Martin has successfully completed acoustic testing of the first
Advanced Extremely High Frequency (AEHF) military communications
satellite. The Advanced EHF system will provide survivable, highly secure,
protected, global communications for all warfighters serving under the
U.S. Department of Defense.

http://spaceflightnow.com/news/n0802/28aehf/


CONCEPT VEHICLE TAKES OFF-ROADING OUT OF THIS WORLD
---------------------------------------------------
In a car commercial, it would sound odd: active suspension, six-wheel
drive with independent steering for each wheel, no doors, no windows, no
seats and the only color available is gold.

http://spaceflightnow.com/news/n0802/27lunartruck/


NEW THEORY OF STAR FORMATION
----------------------------
In order for a rare, massive star to form inside an interstellar cloud of
gas and dust, small "helper" stars about the size of the sun must first
set the stage, according to a new theory proposed by astrophysicists at
the University of California, Berkeley, and Princeton University.

http://spaceflightnow.com/news/n0802/27starformation/

Feature: JPL Helps Shoot for the Moon, Stars, Planets and More

Feature                                                      Mar. 3, 2008

JPL Helps Shoot for the Moon, Stars, Planets and More

The Big Picture

A giant telescope, galaxy maps, and laser beacons on Mars are only a few of the ideas
that teams selected by NASA will study for the next generation of astronomy and
astrophysics missions. NASA's Jet Propulsion Laboratory, Pasadena, Calif., will help
usher in this new era by playing an active role in 15 of the 19 science teams chosen to
look at new concepts for future missions.

The 15 teams will explore concepts for missions to hunt for planets orbiting other stars
(exoplanets) and to answer various astrophysics questions. JPL will manage six exoplanet
and five astrophysics mission concepts and contribute to another four astrophysics
mission plans managed from other NASA centers by aiding engineering and mission
design, refining the science goals and supporting cost estimates.

The final reports will be put up for review in front of the Decadal Survey Committee,
which sets the priorities for astronomy and astrophysics studies every 10 years, said
Michael Werner, the chief scientist for astronomy and physics at JPL.

"We're delighted at JPL's involvement," said Werner, who is also the project scientist of
NASA's Spitzer Space Telescope. "We're looking forward to working with our
government, industrial and academic partners to develop really exciting mission
concepts."

Planets, Planets Everywhere

With half a dozen exoplanet mission concepts in the mix, it's clear the hunt for smaller,
Earthlike planets that might harbor life is very much on the minds of NASA and the
public.

"The idea has been discussed by thinkers going back to the ancient Greeks, Renaissance
thinkers, and all the way up to modern times," said Michael Devirian, manager of the
Exoplanet Exploration Program at JPL, which encompasses NASA's planet-finding
efforts.  "One can imagine primitive man sitting around the campfire, wondering what's
outside the circle of light, just as we now conduct our search, outside the circle of light of
our sun.  The search for other planets touches all of us deep in our psyche, and it's very
easy to relate to and imagine what could be out there."

Planet mania is catching the fancy of the younger generation, according to Jakob Van
Zyl, who heads JPL's Astronomy and Physics Directorate. "Anytime there's an exoplanet
session at a science conference, you have a lot of young people showing up and
interested."

Devirian said NASA plans to issue an announcement of opportunity in 2009 for a
moderate-scale exoplanet mission.

"The concepts that we are working on are candidates for this mission," Devirian said.
"NASA will wait and see what the Decadal Survey Committee has to say before selecting
a mission."

The various exoplanet mission concepts span all the techniques currently being
developed to detect planets, according to Devirian. Several will attempt to zoom in and
image giant planets that orbit around some of our neighboring stars. These studies will
use different types of coronagraphs, mask-like instruments that attach to telescopes to
block the harsh, blinding starlight that hides the dimmer planets. By using coronagraphs,
scientists can find the comparatively miniscule light from planets orbiting close to these
stars. One of these proposed missions combines a coronagraph on the telescope with an
external occulter, a starlight blocker flying separately thousands of kilometers away, in
order to look very close to a star for planets in orbits similar to the orbit of Earth around
our star, the sun.

The remaining two exoplanet mission concepts use interferometers. Interferometers
utilize multiple telescopes to simulate an enormous telescope with great resolving power.

One of the mission concepts will test a nulling interferometer to cancel a star's light with
the goal of imaging giant planets, and, by seeing light from the ring of dust that marks a
planet's orbit, learn about the architectures of planetary systems. The other mission
concept will study a large stellar interferometer--6 meters, or 20 feet long--that could be
used to find planets by measuring the star's "wiggle," or its reciprocal motion with the
planets around it.

"The science of exoplanets is one of the most vibrant and exciting areas to study at this
time," Devirian said. "It is also one of the most challenging, so it's very important to
conduct these studies to come up with the best approaches for these missions."

Meanwhile, Elsewhere in the Universe.......

Van Zyl notes that astrophysics includes other research areas that are also grabbing their
share of attention.  "Astrophysics is a broad field of study, and that fact is manifested in
the wide range of topics these teams are investigating."

The nine astrophysics mission concept studies will range from testing general relativity to
mapping the early universe's rapid expansion. JPL will manage five of these studies. One
of these will perform a systematic study of all astrophysical processes relevant to the
births and deaths of stars in both our galaxy and in nearby galaxies. Another will study
the polarization of the cosmic microwave background, the radiation left over when our
universe was formed. A third will measure the shape of the cosmic inflation potential by
conducting a near-infrared large-area redshift survey capable of detecting galaxies that
formed early in the history of the universe.

Another astrophysics study will explore placing laser beacons on Mars and measuring the
precise distance to perform the most precise test ever of Einstein's theory of general
relativity. Last but not least, two moon-related studies include a "Dark Ages" lunar
interferometer to map out hydrogen gas clouds formed during the early days of the
universe.

JPL will also contribute to astrophysics mission concept studies managed by other NASA
centers, including a study of a giant telescope (eight to 16 meters in diameter, or 26 to 52
feet), and an investigation of the organic molecules floating in the spaces between stars, a
means of looking at the origin of cosmic rays.

Werner said he was pleased that NASA was able to sponsor these studies as a way to
prepare for the Decadal Survey Committee.  "The success of these missions will reflect
the strength of JPL's astrophysics activities," Werner said.

The Who's Who of New Missions!

The 15 selected science teams and their mission concept studies are:

Exoplanet Missions:

*       Access (Actively-Corrected Coronagraphs for Exoplanet System Studies):
comparing coronagraphs for exoplanet missions (JPL both manages the mission
concept study and is home institution for the principal investigator, John Trauger)
*       Davinci (Dilute Aperture Visible Nulling Coronagraph Imager): examining a
nulling interferometer (JPL both manages the mission concept study and is home
institution for the principal investigator, Michael Shao)
*       PECO (Pupil-mapping Exoplanet Coronagraphic Observer): refining a Phase
Induced Amplitude Apodization Coronograph (with principal investigator Olivier
Guyon of the University of Arizona)
*        Epic (Extrasolar Planetary Imaging Coronagraph): directly imaging exoplanets
orbiting nearby stars (with principal investigator Mark Clampin of NASA's
Goddard Space Flight Center)
*       XPC (eXtrasolar Planet Characterizer): examining external and internal
interferometers (with principal investigator David Spergel of Princeton
University)
*       Planet Hunter: examining a six-meter stellar (26-foot) interferometer (with
principal investigator Geoff Marcy of the University of California, Berkeley)

Astrophysics Missions

*       SFO (Star Formation Observatory): studying star formation (with principal
investigator Paul Scowen of Arizona State University)
*       MLR (Mars Laser Ranging): testing general relativity using ranging to Mars (with
principal investigator Tom Murphy of the University of California, San Diego)
*       LARC (Lunar Array for Radio Cosmology): building a lunar array for radio
cosmology (with principal investigator Jacqueline Hewitt of the Massachusetts
Institute of Technology)
*       CIP (Cosmic Inflation Probe): high redshift galaxy survey (with principal
investigator Gary Melnick of the Smithsonian Astrophysical Observatory)
*       Epic (Experimental Probe of Inflationary Cosmology): studying the polarization
of radiation from the cosmic microwave background (with principal investigator
Stephen Meyer of the University of Chicago)
*       Atlast (Advanced Technology Large Aperture Space Telescopes): designing an
eight to 16 meter (26 to 52 feet) optical space telescope (with principal
investigator Marc Postman of the Space Telescope Science Institute)
*       Dali (Dark Ages Lunar Interferometer): detection of low-frequency radio
emissions (with principal investigator Joe Lazio of the Naval Research
Laboratory)
*       Aspire (Astrobiology Space Infrared Explorer): searching for organic molecules
in interstellar space (with principal investigator Scott Sandford of NASA's Ames
Research Center)
*       Oasis (Orbiting Astrophysical Spectrometer In Space): determining the origin of
cosmic rays (with principal investigator James Adams of NASA's Marshall Space
Flight Center)


Media Contacts: Diya Chacko
818-354-9382/818-393-5464
dschacko@jpl.nasa.gov

Jane Platt 818-354-0880
Jet Propulsion Laboratory, Pasadena, Calif.
Jane.platt@jpl.nasa.gov

-end-

Spaceflight Now | Breaking News | Lake Erie crew describes satellite shot

Lake Erie crew describes satellite shot:

 

ARMED FORCES PRESS SERVICE RELEASE

Posted: February 28, 2008

 

PEARL HARBOR, Hawaii - The crewmembers of the USS Lake Erie were calm as they fired the latest shot heard round the world. The Aegis-class cruiser fired the missile that destroyed a dead spy satellite that posed a threat to humans.

Navy Capt. Randall M. Hendrickson, the Lake Erie's commanding officer, spoke to reporters aboard the ship, which has just returned from the mission. The visiting reporters are traveling with Navy Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, who visited the ship.

The captain said the crew worked intensively for a month and a half before the shootdown. "We kept working up with a team of government experts and technicians, as well as industry partners," Hendrickson said.

The group worked to gather information and modify the Standard Missile 3 and the Aegis weapon system, he said. They started tracking the satellite at different times to get radar cross-section data, which helped build the program software, Hendrickson said.

"Obviously there was a lot of anticipation building up each time we practiced, each time we tracked," he said.

The ship's weapons systems officer, Navy Lt. Cmdr. Drew Bates, said the rehearsals really helped when push came to shove. "By the time we did this, we had seen it a hundred times," he said. "We were practicing what to do in case things go wrong. Fortunately nothing went wrong. This went just the way it was designed to happen, and hats off to the industry team for giving the nation a system that was able to have the excess capability to do this."

The satellite was unlike any target the system was designed to go after, the captain said. The satellite was in orbit rather than on a ballistic trajectory. Also, the satellite was traveling at incredible speeds.

The Lake Erie left here the day officials announced President Bush's decision to try to shoot down the satellite. Hendrickson said the ship was in position when the shuttle Atlantis returned from its mission.

The ship received the order that Defense Secretary Robert M. Gates had OK'd the mission at mid-morning. "From that point on, the ship was very calm," Hendrickson said. "Obviously, the closer we got, there was a lot of anticipation. The firing team was very calm when we did it and, with the exception of the Œwhoosh' when it went out of the launcher, it was just as scripted."

He said that when the missile's seeker opened its eyes it had the satellite "right dead center."

When the missile hit the satellite, "there was a lot of cheering" aboard the ship, he said.

The crew knew from the kinetic warhead imagery in the nose of the missile that it was a good hit, the captain said.

"The radar scope went wild," he said. "At that point, there was a lot of debris, a lot of pieces and, at that point, we thought we had a pretty good impact. Then that was confirmed by the aircraft that were airborne, the radars ashore and some other sensors that it was pretty much obliterated. Over the next three to four hours, a lot of it was burning up as it was coming down, which was the whole point of it."

Civilian experts from the Navy facility in Dahlgren, Va., and contractors from Lockheed Martin and from Raytheon Co. helped the crew prepare for the shot. But Navy sailors manned the consoles for the mission.

Everyone on the USS Lake Erie contributed, the captain said. "Whatever the task is, there's no small task on a ship," he said.

The reaction of the crew is unbelievable, said Command Master Chief Petty Officer Mack Ellis, the highest-ranking enlisted sailor on the Lake Erie. "Even the youngest sailor who didn't understand it at first, every time they walk somewhere and people know they are from Lake Erie, they say congratulations. It puts a smile of their face and makes their day".

Spaceflight Now | Breaking News | Spacecraft at Mars prepare for new kid on the block

Spacecraft at Mars prepare for new kid on the block:

 

NASA/JPL NEWS RELEASE

Posted: February 28, 2008

 

Three Mars spacecraft are adjusting their orbits to be over the right place at the right time to listen to NASA's Phoenix Mars Lander as it enters the Martian atmosphere on May 25.

Every landing on Mars is difficult. Having three orbiters track Phoenix as it streaks through Mars' atmosphere will set a new standard for coverage of critical events during a robotic landing. The data stream from Phoenix will be relayed to Earth throughout the spacecraft's entry, descent and landing events. If all goes well, the flow of information will continue for one minute after touchdown.

"We will have diagnostic information from the top of the atmosphere to the ground that will give us insight into the landing sequence," said David Spencer of NASA's Jet Propulsion Laboratory, Pasadena, Calif., deputy project manager for the Phoenix Mars Lander project.

This information would be valuable in the event of a problem with the landing and has the potential to benefit the design of future landers.

Bob Mase, mission manager at JPL for NASA's Mars Odyssey orbiter, said, "We have been precisely managing the trajectory to position Odyssey overhead when Phoenix arrives, to ensure we are ready for communications. Without those adjustments, we would be almost exactly on the opposite side of the planet when Phoenix arrives."

NASA's Mars Reconnaissance Orbiter is making adjustments in bigger increments, with one firing of thrusters on Feb. 6 and at least one more planned in April. The European Space Agency's Mars Express orbiter has also maneuvered to be in place to record transmissions from Phoenix during the landing. Even the NASA rovers Spirit and Opportunity have been aiding preparations, simulating transmissions from Phoenix for tests with the orbiters.

Launched on Aug. 4, 2007, Phoenix will land farther north than any previous mission to Mars, at a site expected to have frozen water mixed with soil just below the surface. The lander will use a robotic arm to put samples of soil and ice into laboratory instruments. One goal is to study whether the site has ever had conditions favorable for supporting microbial life.

Phoenix will hit the top of the Martian atmosphere at 5.7 kilometers per second (12,750 miles per hour). In the next seven minutes, it will use heat-shield friction, a parachute, then descent rockets to slow to about 2.4 meters per second (5.4 mph) before landing on three legs.

Odyssey will tilt from its normally downward-looking orientation to turn its ultrahigh-frequency (UHF) antenna toward the descending Phoenix. As Odyssey receives a stream of information from Phoenix, it will immediately relay the stream to Earth with a more capable high-gain antenna.

The other two orbiters, Mars Reconnaissance Orbiter and Mars Express, will record transmissions from Phoenix during the descent, as backup to ensure that all data is captured, then transmit the whole files to Earth after the landing.

"We will begin recording about 10 minutes before the landing," said JPL's Ben Jai, mission manager for Mars Reconnaissance Orbiter.

The orbiters' advance support for the Phoenix mission also includes examination of potential landing sites, which is continuing. After landing, the support will include relaying communication between Phoenix and Earth during the three months that Phoenix is scheduled to operate on the surface. Additionally, NASA and European Space Agency ground stations are performing measurements to determine the trajectory of Phoenix with high precision.

With about 160 million kilometers (100 million miles) still to fly as of late February, Phoenix continues to carry out testing and other preparations of its instruments. The pressure and temperature sensors of the meteorological station provided by the Canadian Space Agency were calibrated Feb. 27 for the final time before landing.

"The spacecraft has been behaving so well that we have been able to focus much of the team's attention on preparations for landing and surface operations," Spencer said.

The Phoenix mission is led by Peter Smith of the University of Arizona, Tucson, with project management at JPL and development partnership at Lockheed Martin, Denver. International contributions are provided by the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus, Denmark; the Max Planck Institute, Germany; and the Finnish Meteorological Institute. JPL, a division of the California Institute of Technology in Pasadena, manages Mars Odyssey and Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington.