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Space Shuttle Endeavour Lifts Off, Begins Earth Mapping Mission

Date:
February 14, 2000
Source:
NASA/Johnson Space Center
Summary:
Endeavour astronauts began mapping operations on the Shuttle Radar Topography Mission, which will provide maps of the Earth unprecedented in accuracy and uniformity.
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FULL STORY

NOTE: The following are the first six status reports issued by NASA highlighting the activities of the Space Shuttle Endeavour, which blasted off Feb. 11 from the Kennedy Space Center.

STS-99 Mission Status Report, #06 -- Issued Feb. 13, 2000

The Shuttle Radar Topography Mission’s mapping operation continues to run smoothly, with about 17.7 million square miles of the Earth’s surface having been mapped by 7 p.m. Central time. Scientists also reported that 38 percent of landmasses had been mapped thus far in the flight. Despite a problem with a small nitrogen thruster on the end of the 200-foot-long mast, both the C-band and X-band radars continue to perform as expected, and the thruster problem has had no impact on mapping operations.

“We are starting to see the first ‘quick look’ results from the X-band and C-band antennas and the details are fantastic,” said Dr. Michael Kobrick, SRTM project scientist. “Even in this lower resolution, quick-look results, we can see many topographic features that were completely invisible in the best maps we have today.”

Two members of the Blue Team – Dom Gorie and Mamoru Mohri – spent a fewminutes early this morning talking to Dr. Bob Ballard, discoverer of the RMS Titanic and founder of the JASON Foundation, an educational program designed to spark students’ interest in science and technology. They also took questions from the Fox News Network.

Endeavour’s crew and flight controllers continue troubleshooting a problem with asmall nitrogen thruster mounted at the tip of the radar’s outboard antenna. Although gaseous nitrogen propellant is flowing, little or no thrust is being produced. Crew members cycled the valve open and closed in an attempt to pinpoint the problem. Controllers plan to leave the valve closed for several hours to attempt to quantify the rate of propellant usage. The thruster was designed to keep the mast from “righting” itself in response to Earth’s gravity and remove the need for additional orbiter thruster firings to keep the antenna in its data-taking position. Without the thruster on the antenna, crew members have to fire the orbiter’s thrusters more than expected.

As the Blue Team wrapped up its third day in space, the Red Team of KevinKregel, Janet Kavandi and Gerhard Thiele took over mapping operations shortly after their wake-up call this morning. Gorie, Mohri and Janice Voss turned in shortly after 2 p.m., with a wake-up call set for 10:14 tonight to begin their fourth day of mapping activities.

Controllers also did some troubleshooting on one of the on-board cameras after Gorie reported the system that records the time at which images are taken was not working. Controllers suspect that the batteries were weakened due to the delay in launching Endeavour. The weak batteries should have no impact on the use of the camera to support NASA’s Earth observation program.

After yesterday’s repositioning of a camera bracket on the flight deck, EarthKam operations continue nominally. As of late this afternoon, some 355 images had been downlinked from the EarthKam. This NASA program allows students to useinteractive Web pages to target and select images to be photographed from a camera onboard the shuttle. All of Endeavour’s spacecraft systems are continuing to function normally as it circles the Earth every 90 minutes at an altitude of about 150 miles.

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STS-99 Mission Status Report, #05 -- Issued Feb. 13, 2000

The first “flycast maneuver” trim burn was completed without a hitch by members of the Endeavour crew early Sunday. A little later, the Payload Operations Center reported that the Shuttle Radar Topography Mission had successfully mapped 7.64 million square miles as of very early Sunday morning.

The flycast maneuver is designed to reduce strain on the almost-200-foot mast extending from Endeavour’s cargo bay. The orbiter, which flies tail-first during mapping operations, is moved to a nose-first attitude with the mast extending upward. A brief reaction control system pulse begins the maneuver. The mast deflects slightly backwards, then rebounds forward. As it reaches vertical, a stronger thrust is applied, arresting the mast’s motion and increasing the orbiter’s speed.

For this mission Endeavour is in a comparatively low orbit, and is slowed by the upper fringes of the Earth’s atmosphere, which causes it to lose altitude. The crew will make daily flycast maneuver trim burns to keep the spacecraft in the proper altitude for mapping.

Endeavour’s Red Team, Commander Kevin Kregel, and Mission Specialists Janet Kavandi and Gerhard Thiele, began their eight-hour sleep period shortly after the trim burn. Blue Team members went on duty at about 12:30 a.m. Sunday.

Working around the clock in the two shifts, crewmembers will map an area from 60 degrees north to 56 degrees south. The area includes all the southern continents except Antarctica, and northern continents south of a line from the southern tip of Greenland, southern Alaska and through St. Petersburg, Russia. The area includes about 95 percent of the Earth’s population.

All of the orbiter’s systems continue to function normally. Crewmembers and flight controllers in Houston continue to look at the cold gas jet on the end of the SRTM’s outboard antenna. They are looking at consumption of propellant and the lack of thrust from that jet, designed to help maintain the attitude of the mast. The balky jet is having no impact on the mission's mapping activities.

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STS-99 Mission Status Report, #04 -- Issued Feb. 12, 2000

By the time members of Endeavour’s Red Team had reached lunchtime on this first full day in space for the Shuttle Radar Topography Mission, the radar antennas in the payload bay and at the end of a 200-foot mast had mapped about 1.7 million square miles (4.5 million square kilometers) of the Earth’s surface, or the equivalent of about half the area of the United States.

The crew is working around the clock, in two shifts, to collect data that will produce maps of the Earth with unprecedented accuracy and uniformity. Mapping operations will continue for 10 days, and are proceeding very smoothly. SRTM will cover the area between 60 degrees north and 56 degrees south, roughly the area between St. Petersburg, Russia to the north and the tip of South America to the south. The area to be mapped is home to about 95 percent of the Earth’s population. In all, more than 70 percent of the Earth’s surface will be mapped.

The first X-band image – of the area near White Sands, New Mexico – was released this afternoon, and scientists expressed their delight with the quality of the image. X-band images will be posted to the German Space Agency web site at http://www.dfd.dlr.de/srtm/html/newtoday_en.htm. Both the C-band and X-band radars continue to perform as expected.

“The data we’ve seen so far looks just terrific,” said Dr. Michael Kobrick, project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, CA. “The mapping plan is right on schedule.”

Early this afternoon, crew member Kevin Kregel fired the shuttle’s thruster jets in a series of pulsed burns to measure the movement of the rigid mast extending over Endeavour’s left wing. Flight controllers reported the tip of the mast moved only 11 inches, just as predicted, despite the fact the antenna’s dampers remained locked in position. The firings were necessary to determine how they affect the mast, prior to upcoming maneuvers to raise Endeavour’s orbit.

Endeavour’s crew also downlinked launch video from an in-cabin camera, providing a unique perspective of yesterday’s flawless launch.

All of Endeavour’s payload and spacecraft systems are continuing to function normally.

STS-99 Mission Status Report, #03 -- Issued Feb. 12, 2000

Endeavour astronauts began mapping operations on the Shuttle Radar Topography Mission, which will provide maps of the Earth unprecedented in accuracy and uniformity. The first swath was begun as the orbiter crossed over southern Asia and continued until Endeavour flew over the continent’s eastern coast and moved over the northern Pacific Ocean. The mapping will continue through the mission until the antenna mast is retracted before landing.

Because of the 24-hour-a-day activity aboard Endeavour, the six crewmembers are divided into two teams. Blue Team members Dom Gorie, Janice Voss and Mamoru Mohri began the first mapping swath, covering a 140-mile-wide path, at about 11:31 p.m. Friday. It was the beginning of coverage of more than 70 percent of the Earth’s land surface. The mapping will cover an area between 60 degrees north and 56 degrees south, where about 95 percent of the Earth’s population lives.

The Red Team, led by Mission Commander Kevin Kregel, includes Mission Specialists Janet Kavandi and Gerhard Thiele. Their first shift was intense. It included deployment and checkout of the almost 200-foot mast supporting the outboard antenna structure. It is the largest rigid structure ever deployed in space. The Red Team began its sleep period at about 10:45 p.m. Friday and are scheduled to be awakened at 6:44 this morning.

After mast deployment, tests revealed that the mast’s damping system, designed as a kind of a shock absorber for the mast, was not working as expected. Flight controllers decided to leave the dampers in their locked position. Calculations showed that the mast was at no risk without the dampers activated.

All planned science data takes have been acquired successfully and all indications from the telemetry show that the radars are performing nominally. Data has been sent to JPL for analysis and early indications are that the data is of excellent quality. Additional reports about mapping results are expected about 12:00 noon CST.

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STS-99 Mission Status Report, #02 -- Issued Feb. 11, 2000

Space shuttle astronauts deployed the longest rigid structure ever built in space today and continued work to check out the equipment they will use to produce unrivaled three-dimensional images of the Earth’s surface.

Red Team leader Commander Kevin Kregel, and colleagues Janet Kavandi and Gerhard Thiele initiated extension of the radar mast at 5:27 p.m. CST. After 17 minutes, all 87 cube-shaped bays of the carbon fiber-reinforced plastic, stainless steel, alpha titanium, and Invar structure were deployed by 5:44 p.m. Total length of the mast was 60.95 meters, or just under 200 feet.

The crew also maneuvered the shuttle into the proper attitude, or orientation, for mapping. This orientation points the shuttle payload bay – and its inboard and outboard radar antennas – at the Earth. Endeavour’s tail is leading the way as the shuttle orbits about 150 statute miles above the surface. The Red Team then began a series of jet thruster firings to test the ability of dampers to absorb the force of planned maneuvering jet firings and keep the inboard and outboard antennas properly aligned. This alignment is crucial for scientists who will need to combine the radar images received by the two sets of antennas.

The Shuttle Radar Topography Mission will record radar data in both C-band and X-band radar wavelengths. This data eventually will be processed into 3-D maps of the Earth that are 30 times more exact that those currently available. These maps will be important to scientists in many disciplines, ranging from ecology to geology to hydrology, as well as a number of military and commercial applications. As the Red Team performed the checkout procedures, Blue Team members Dom Gorie, Janice Voss and Mamoru Mohri set up the shuttle’s network of portable computers and began an abbreviated six-hour sleep period at 3:44 p.m. They’ll be awakened at 9:44 p.m. to begin radar mapping operations late tonight.

Endeavour is orbiting the Earth in an orbit inclined 57 degrees to either side of the Equator for the radar mapping of a majority of the Earth’s surface. The shuttle completes one orbit every 90 minutes at an altitude of about 150 statute miles.

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STS-99 Mission Status Report, #01 -- Issued Feb. 11, 2000

With six astronauts on board, Endeavour sped to orbit under cloudless skies from the Kennedy Space Center today to begin the Shuttle Radar Topography Mission, the first human space flight of the 21st century.

Commander Kevin Kregel, Pilot Dom Gorie, and Mission Specialists Janice Voss, Janet Kavandi, Gerhard Thiele and Mamoru Mohri blasted off 14 minutes into the available 2 hour plus launch window at 11:44 a.m. Central time after a near flawless countdown, and arrived on orbit 8 ½ minutes later. The slight delay in launching Endeavour was due to the launch team needing a few minutes to resolve some minor technical issues before proceeding with the final portion of the countdown.

The STS-99 crew's first tasks were to set up Endeavour for dual shift, round-the-clock operations using a trio of radar systems mounted in the cargo bay for the most comprehensive three-dimensional map of the Earth ever attempted.

Once Endeavour’s payload bay doors are opened, the Red team of Kregel, Kavandi and Thiele will begin to activate the Shuttle radar instruments, and will prepare for the deployment of a 200-foot long boom over the left wing of the orbiter on which two of the radar systems are housed. That boom deploy will begin about 5 ½ hours into the mission.

Kregel, Kavandi and Thiele will conduct a series of jet thruster firings once the boom is deployed to test its ability to flex properly and will set up recorders on board on which the radar data will be stored for downlink to mission scientists on the ground.

Meantime, the Blue team of Gorie, Voss and Mohri will begin an abbreviated six hour sleep period at 3:44 p.m. They’ll be awakened at 9:44 p.m., soon after the radar boom has been checked out, to begin radar mapping operations late tonight.

Endeavour is orbiting the Earth in an orbit inclined 57 degrees to either side of the Equator for the radar mapping of around 80 per cent of the Earth’s surface. Endeavour is orbiting the planet every 90 minutes at an altitude of about 127 nautical miles.


Story Source:

Materials provided by NASA/Johnson Space Center. Note: Content may be edited for style and length.


Cite This Page:

NASA/Johnson Space Center. "Space Shuttle Endeavour Lifts Off, Begins Earth Mapping Mission." ScienceDaily. ScienceDaily, 14 February 2000. <www.sciencedaily.com/releases/2000/02/000214071834.htm>.
NASA/Johnson Space Center. (2000, February 14). Space Shuttle Endeavour Lifts Off, Begins Earth Mapping Mission. ScienceDaily. Retrieved April 24, 2024 from www.sciencedaily.com/releases/2000/02/000214071834.htm
NASA/Johnson Space Center. "Space Shuttle Endeavour Lifts Off, Begins Earth Mapping Mission." ScienceDaily. www.sciencedaily.com/releases/2000/02/000214071834.htm (accessed April 24, 2024).

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