Nov. 10, 1999
Focused on the upcoming landing of NASA's Mars Polar Lander, these actions include: a newly assigned senior management leader, freshly reviewed and augmented work plans, detailed fault tree analyses for pending mission events, daily telecons to evaluate technical progress and plan work yet to be done, increased availability of the Deep Space Network for communications with the spacecraft, and independent peer review of all operational and contingency procedures.
The board recognizes that mistakes occur on spacecraft projects, the report said. However, sufficient processes are usually in place on projects to catch these mistakes before they become critical to mission success. Unfortunately for MCO, the root cause was not caught by the processes in place in the MCO project.
"We have mobilized the very best talent at the Jet Propulsion Laboratory (JPL) to respond thoroughly to the specific recommendations in the board's report and the other areas of concern highlighted by the board," said Dr. Edward Stone, director of JPL. "Special attention is being directed at navigation and propulsion issues, and a fully independent 'red team' will review and approve the closure of all subsequent actions. We are committed to doing whatever it takes to maximize the prospects for a successful landing on Mars on Dec. 3."
The failure board's first report identifies eight contributing factors that led directly or indirectly to the loss of the spacecraft. These contributing causes include inadequate consideration of the entire mission and its post-launch operation as a total system, inconsistent communications and training within the project, and lack of complete end-to-end verification of navigation software and related computer models.
"The 'root cause' of the loss of the spacecraft was the failed translation of English units into metric units in a segment of ground-based, navigation-related mission software, as NASA has previously announced," said Arthur Stephenson, chairman of the Mars Climate Orbiter Mission Failure Investigation Board. "The failure review board has identified other significant factors that allowed this error to be born, and then let it linger and propagate to the point where it resulted in a major error in our understanding of the spacecraft's path as it approached Mars.
"Based on these findings, we have communicated a range of recommendations and associated observations to the team planning the landing of the Polar Lander, and the team has given these recommendations some serious attention," said Stephenson, director of NASA's Marshall Space Flight Center, Huntsville, AL.
The board's report cites the following contributing factors:
The failure board will now proceed with its work on a second report due by Feb. 1, 2000, which will address broader lessons learned and recommendations to improve NASA processes to reduce the probability of similar incidents in the future.
Mars Climate Orbiter and its sister mission, the Mars Polar Lander, are part of a series of missions in a long-term program of Mars exploration managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. JPL's industrial partner is Lockheed Martin Astronautics, Denver, CO. JPL is a division of the California Institute of Technology, Pasadena, CA.
The Board's report is available on-line.
Charts used in the briefing today are available on-line.
NASA Headquarters, Washington, DC
Jet Propulsion Laboratory, Pasadena, CA
Lockheed Martin Astronautics, Denver, CO
"People sometimes make errors," said Dr. Edward Weiler, NASA's Associate Administrator for Space Science. "The problem here was not the error, it was the failure of NASA's systems engineering, and the checks and balances in our processes to detect the error. That's why we lost the spacecraft."
The peer review preliminary findings indicate that one team used English units (e.g., inches, feet and pounds) while the other used metric units for a key spacecraft operation. This information was critical to the maneuvers required to place the spacecraft in the proper Mars orbit.
"Our inability to recognize and correct this simple error has had major implications," said Dr. Edward Stone, director of the Jet Propulsion Laboratory. "We have underway a thorough investigation to understand this issue."
Two separate review committees have already been formed to investigate the loss of Mars Climate Orbiter: an internal JPL peer group and a special review board of JPL and outside experts. An independent NASA failure review board will be formed shortly.
"Our clear short-term goal is to maximize the likelihood of a successful landing of the Mars Polar Lander on December 3," said Weiler. "The lessons from these reviews will be applied across the board in the future."
Mars Climate Orbiter was one of a series of missions in a long-term program of Mars exploration managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. JPL's industrial partner is Lockheed Martin Astronautics, Denver, CO. JPL is a division of the California Institute of Technology, Pasadena, CA.
CNN Poll: After the failure of the Mars Climate Observer, should NASA continue its planned Mars missions?
Yes, the successes are worth the failures 46831 votes (70%) Not withouth major staff changes 13952 votes (21%) No, it's a big waste 6329 votes ( 9%) Total: 67,112 votes
25 Sep 1999
TSE - THE SPACE EXPERIENCE
Officials want to make sure nothing will endanger another probe, Mars Polar Lander, which is headed for a Dec. 3 landing on the planet to search for water ice near the south pole.
A navigation error put Climate Orbiter on a path too close to Mars, where it presumably was torn apart and burned up in the planet's atmosphere.
"We want to understand what happened here because we need to understand if there are any implications for the Mars Polar Lander," said Richard Zurek, project scientist for the December mission.
"It has some pretty tight navigation requirements so we are looking (for answers) with that in mind."
Climate Orbiter was at the end of a 416-million-mile journey Thursday when it began firing its engine to slide into orbit around Mars on a mission to study the weather.
But NASA lost contact with the spacecraft, and officials later determined it had gone within 35 miles of the surface where it would have been exposed to intense heat and friction in the atmosphere.
Controllers never intended it to get closer than a safe 90 miles above ground.
Three separate teams got to work Friday investigating the mishap, while others forged ahead with preparations for Polar Lander's arrival. As part of their normal work, engineers plan to refine the ship's course in upcoming weeks.
They must direct it to land within an area 12 miles wide and 125 miles long so it can perform its science work.
"We need to understand what the nature of the (Climate Orbiter) problem is and to make sure it's not going on elsewhere," said Mary Hardin, a spokeswoman at NASA's Jet Propulsion Laboratory, where the spacecraft is controlled.
She said Climate Orbiter's failure was not affecting the team's focus.
"We are determined," she said. "People know they have another mission behind this one, and they are really getting down to business."
Mars Polar Lander was launched from Cape Canaveral Air Station in January after its cousin, Climate Orbiter, was sent on its way in December.
Orbiter was to settle around Mars early Thursday, refine its path by late November and be in postion to help Polar Lander when it arrived Dec. 3.
The orbiter would have served as a communication link between Earth and the lander, which would send data back to controllers via the spacecraft. NASA would have sent commands to the lander through the orbiter as well.
With that ability lost, engineers are working to ensure Polar Lander's mission will go smoothly. The lander is equipped with its own antenna that it can use to speak directly to controllers on Earth.
Another spacecraft already in orbit, Mars Global Surveyor, may be enlisted to help with communications. In any case, scientists expect to get a full science mission from Polar Lander.
But the loss of Climate Orbiter complicates matters. Having the lander talk via its antenna, for example, could get muddled if the Martian weather is hazy or dusty.
"In that case, we would not be able to run the direct Mars-to-Earth link as much as we'd like," Zurek said.
Meantime, Mars scientists across the country came quickly to grips Friday with the loss of the orbiter. While disappointed, many said they think NASA's Mars program will rebound easily.
Mars Climate Orbiter is among a small armada of craft planned for launch through 2005 on missions to study the planet exhaustively and especially look for signs of past or present life.
"It's a terrible loss, and I don't mean to minimize it, but it doesn't feel to me that it's of the same scope we used to have when we lost a spacecraft and you could see 10 years of your life going up in smoke," said Chris McKay, a planetary scientist at NASA's Ames Research Center in Mountain View, Calif.
"Now we have a program that's much more capable, much more flexible, and you can lose a spacecraft and it's not the end of the world."
Climate Orbiter carried two instruments: One to track water vapor, dust and ozone in the planet's atmosphere, and a camera to take unprecedented color images of the surface.
The spacecraft would have produced the first global weather study on the planet, following the changes from season to season for a full Martian year of 687 days.
"A whole bunch of missions are going to happen in the next decade so the whole thing doesn't fall apart if one mission fails, but even so, each mission has a unique aspect to it," said Jim Bell, an astronomer at Cornell University in Ithaca, N.Y. and a member of the lost spacecraft's science team. "And Mars Climate Orbiter's aspect was the climate.
"So clearly, there's going to be a gap now in our understanding of the climate. Most of us are hoping NASA can find some way of filling that gap in."
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According to Project Manager Richard Cook, data obtained several hours before arrival indicates that the spacecraft was going to pass only 60 km from the Martian surface, rather than the planned close approach of 140 to 150 km. Since engineers consider 85 km the minimum safe altitude, the initial speculation is that MCO seriously overheated as it passed through the planet's upper atmosphere and perhaps broke apart from aerodynamic stress. No one yet knows how the spacecraft got so far off course. A final trajectory correction on September 15th, involving a 15-second engine burn, was apparently executed successfully.
MCO was to serve as the telecommunications relay for the Mars Polar Lander, which will arrive on December 3rd and touch down on a sediment plain near the planet's south pole. Fortunately, MPL carries a radio for direct communication with Earth, though at a slower data rate. The Mars Global Surveyor, which has been orbiting Mars for two years, can also serve as a data relay.
The loss of Mars Climate Orbiter rekindles memories of another NASA spacecraft, Mars Observer, which mysteriously disappeared without a trace on August 21, 1993 -- just three days before its arrival. Notably, MCO carried the backup of an atmospheric-sounding instrument that had been aboard Mars Observer. This double blow will affect scientists' ability to monitor the planet's global weather. However, points out Carl Pilcher, NASA assistant associate administrator, many Mars-bound spacecraft are in NASA's plans. "We should think of this not as science lost, but as science deferred," Pilcher said Thursday.
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JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
September 23, 1999
Early this morning at about 2 a.m. Pacific Daylight Time the orbiter fired its main engine to go into orbit around the planet. All the information coming from the spacecraft leading up to that point looked normal. The engine burn began as planned five minutes before the spacecraft passed behind the planet as seen from Earth. Flight controllers did not detect a signal when the spacecraft was expected to come out from behind the planet.
"We had planned to approach the planet at an altitude of about 150 kilometers (93 miles). We thought we were doing that, but upon review of the last six to eight hours of data leading up to arrival, we saw indications that the actual approach altitude had been much lower. It appears that the actual altitude was about 60 kilometers (37 miles). We are still trying to figure out why that happened," said Richard Cook, project manager for the Mars Surveyor Operations Project at NASA's Jet Propulsion Laboratory. "We believe that the minimum survivable altitude for the spacecraft would have been 85 kilometers (53 miles)."
"If in fact we have lost the spacecraft it is very serious, but it is not devastating to the Mars Surveyor Program as a whole. The program is flexible enough to allow us to recover the science return of Mars Climate Orbiter on a future mission. This is not necessarily science lost; it is science delayed," said Dr. Carl Pilcher, science director for Solar System Exploration at NASA Headquarters, Washington, D.C. "We have a robust program to explore Mars that involves launching on average one mission per year for at least a decade. It began with the launch of Mars Pathfinder and Mars Global Surveyor in 1996, continued with Mars Climate Orbiter and Mars Polar Lander and will be followed by more missions in 2001, 2003 and 2005. In fact, Mars Polar Lander will arrive in just over two months and its mission is completely independent of the Mars Climate Orbiter. The science return of that mission won't be affected."
Flight controllers at NASA's Jet Propulsion Laboratory in Pasadena, CA and Lockheed Martin Astronautics in Denver, CO will continue their efforts to locate the spacecraft through the Deep Space Network during the next several hours. A special investigation team has been formed by JPL to further assess the situation.
Mars Climate Orbiter is one of a series of missions in a long-term program of Mars exploration known as the Mars Surveyor Program that is managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. JPL is a division of the California Institute of Technology, Pasadena, CA.
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NASA Space Science News for September 21, 1999
Weather Satellite Nears Mars: Mars Climate Orbiter is set to go into orbit around the red planet this week. It will become the first interplanetary weather satellite and a communications relay for the next lander mission to explore Mars
NASA Headquarters, Washington, DC
Jet Propulsion Laboratory, Pasadena, CA
September 20, 1999
In addition to observing the seasonal climate and daily weather of Mars, the orbiter will serve as a communications relay for the Mars Polar Lander, due to set down on layered terrain near the south pole of the red planet on Dec. 3, 1999.
NASA TV will carry a live feed from orbiter mission control facilities at both the Jet Propulsion Laboratory (JPL), Pasadena, CA, and Lockheed Martin Astronautics, Denver, CO. The feed will begin at 4:30 a.m. EDT and run through 5:45 a.m. (1:30 a.m. to 2:45 a.m. PDT). Animation and video footage related to the mission will run on the NASA TV Video File beginning on Tuesday, September 21.
Los Angeles-area reporters are invited to JPL to watch the event in the von Karman Auditorium. Media relations staff will be on hand to arrange interviews.
At 11 a.m. EDT (8 a.m. PDT) on Thursday, Sept. 23, there will be a mission status briefing from JPL that will summarize the results of the Mars orbit insertion activities and provide a preview of mission operations.
A text press kit with graphics and full details on the mission is available on the Internet:
NASA Television is broadcast on the satellite GE-2, transponder 9C, C band, 85 degrees west longitude, frequency 3880.0 MHz, vertical polarization, audio monaural at 6.8 MHz.
September 15, 1999
"After traveling 670 million kilometers (416 million miles) during the last nine months, Mars Climate Orbiter is now ready for its most dramatic moment, the orbit insertion burn," said Dr. Sam Thurman, the flight operations manager for the orbiter at NASA's Jet Propulsion Laboratory. "The spacecraft is on a course that will pass just 193 kilometers (120 miles) over the north pole of Mars, at which point it will fire its main engine to brake into orbit."
Tomorrow, flight controllers will send the spacecraft a set of commands that will automatically execute the orbit insertion maneuver on September 23. These commands will be updated on September 20 to allow for a planned fine-tuning of the desired orbit-insertion flight path.
The orbiter is now 2.24 million kilometers (1.39 million miles) from Mars, traveling at a speed of 3.3 kilometers per second (7,380 miles per hour).
Mars Climate Orbiter will study the weather and climate of Mars and act as a communications relay for the Mars Polar Lander when that spacecraft arrives at the red planet on December 3.
The Mars Climate Orbiter and Mars Polar Lander missions are managed by JPL for NASA's Office of Space Science, Washington, DC. JPL is a division of the California Institute of Technology, Pasadena, CA.
Jet Propulsion Laboratory
14 Sep 1999
Mars Climate Orbiter MOI Timeline September 23, 1999 All times in Earth Receive Time (ERT). One way light time from Mars is 10 minutes 55 seconds. Event PDT EDT UTC Orbiter stows solar array 01:41 04:41 08:41 Orbiter turns to correct orientation to begin main engine burn 01:50 04:50 08:50 Orbiter fires pyrotechnic devices which open valves to begin 01:56 04:56 08:56 pressurizing the fuel and oxidizer tanks Main engine burn starts, fires for 16 minutes 23 seconds. 02:01 05:01 09:01 Orbiter passes behind Mars, out of view from Earth 02:06 05:06 09:06 Main engine burn ends 02:17 05:17 09:17 Orbiter turns to orientation which will allow Earth contact 02:19 05:19 09:19 Orbiter comes out from behind Mars, flight controllers regain contact 02:27 05:27 09:27 Solar array unstows 02:30 05:30 09:30
Mars Climate Orbiter was launched on December 11, 1998 from a Delta II launch vehicle at Cape Canaveral Air Station, Florida. The spacecraft carries instruments to seek clues to the history of climate change on Mars, and will map the Martian surface and profile the structure of the atmosphere.
The orbiter, along with the Mars Polar Lander, are the second installment in NASA's long-term program of robotic exploration of Mars, which was initiated with the 1996 launches of the currently orbiting Mars Global Surveyor and the Mars Pathfinder lander and rover.
The 1998 missions will advance our understanding of Mars' climate history and the planet's current water resources by digging into the enigmatic layered terrain near one of its poles for the first time. Instruments onboard the orbiter and lander will analyze surface materials, frost, weather patterns and interactions between the surface and atmosphere to better understand how the climate of Mars has changed over time.
Key scientific objectives are to determine how water and dust move about the planet and where water, in particular, resides on Mars today. Water once flowed on Mars, but where did it go? Clues may be found in the geologic record provided by the polar layered terrain, whose alternating bands of color seem to contain different mixtures of dust and ice. Like growth rings of trees, these layered geological bands may help reveal the secret past of climate change on Mars and help determine whether it was driven by a catastrophic change, episodic variations or merely a gradual evolution in the planet's environment.
Today the Martian atmosphere is so thin and cold that it does not rain; liquid water does not last on the surface, but quickly freezes into ice or evaporates and resides in the atmosphere. The temporary polar frosts which advance and retreat with the seasons are made mostly of condensed carbon dioxide, the major constituent of the Martian atmosphere. But the planet also hosts both water-ice clouds and dust storms, the latter ranging in scale from local to global. If typical amounts of atmospheric dust and water were concentrated today in the polar regions, they might deposit a fine layer every year, so that the top meter (or yard) of the polar layered terrains could be a well-preserved record showing 100,000 years of Martian geology and climatology.
Next week, Mars Climate Orbiter will fire its main engine to put itself into an elliptical orbit around Mars. The spacecraft will then skim through Mars' upper atmosphere for several weeks in a technique called aerobraking to reduce velocity and circularize its orbit. Friction against the spacecraft's single, 5.5-meter-long (18-foot) solar array will slow the spacecraft as it dips into the atmosphere each orbit, reducing its orbit period from more than 14 hours to 2 hours.
Finally, the spacecraft will use its thrusters to settle into a polar, nearly circular orbit averaging 421 kilometers (262 miles) above the surface. From there, the orbiter will await the arrival of Mars Polar Lander and serve as a radio relay satellite during the lander's surface mission. After the lander's mission is over, the orbiter will begin routine monitoring of the atmosphere, surface and polar caps for a complete Martian year (687 Earth days), the equivalent of almost two Earth years.
The orbiter carries two science instruments: the Pressure Modulator Infrared Radiometer, a copy of the atmospheric sounder on the Mars Observer spacecraft lost in 1993, and the Mars Color Imager, a new, light-weight imager combining wide-and medium-angle cameras. The radiometer will measure temperatures, dust, water vapor and clouds by using a mirror to scan the atmosphere from the Martian surface up to 80 kilometers (50 miles) above the planet's limb.
Meanwhile, the imager will gather horizon-to-horizon images at up to kilometer-scale (half-mile-scale) resolutions, which will then be combined to produce daily global weather images. The camera will also image surface features and produce a map with 40-meter (130-foot) resolution in several colors, to provide unprecedented views of Mars' surface.
Mars Polar Lander, launched a month after the orbiter, will arrive on December 3, 1999, two to three weeks after the orbiter has finished aerobraking. The lander is aimed toward a target sector within the edge of the layered terrain near Mars' south pole.
Like Mars Pathfinder, Mars Polar Lander will dive directly into the Martian atmosphere, using an aeroshell and parachute scaled down from Pathfinder's design to slow its initial descent. The smaller Mars Polar Lander will not use airbags, but instead will rely on onboard guidance and retro-rockets to land softly on the layered terrain near the south polar cap a few weeks after the seasonal carbon dioxide frosts have disappeared. After the heat shield is jettisoned, a camera will take a series of pictures of the landing site as the spacecraft descends.
As it approaches Mars about 10 minutes before touchdown, the lander will release the two Deep Space 2 microprobes. Once released, the projectiles will collect atmospheric data before they crash at about 200 meters per second (400 miles per hour) and bury themselves beneath the Martian surface. The microprobes will test the ability of very small spacecraft to deploy future instruments for soil sampling, meteorology and seismic monitoring. A key instrument will draw a tiny soil sample into a chamber, heat it and use a miniature laser to look for signs of vaporized water ice.
About 100 kilometers (60 miles) away from the microprobe impact sites, Mars Polar Lander will dig into the top of the terrain using a 2-meter-long (6-1/2-foot) robotic arm. A camera mounted on the robotic arm will image the walls of the trench, viewing the texture of the surface material and looking for fine-scale layering. The robotic arm will also deliver soil samples to a thermal and evolved gas analyzer, an instrument that will heat the samples to detect water and carbon dioxide. An onboard weather station will take daily readings of wind temperature and pressure, and seek traces of water vapor. A stereo imager perched atop a 1.5-meter (5-foot) mast will photograph the landscape surrounding the spacecraft. All of these instruments are part of an integrated science payload called the Mars Volatiles and Climate Surveyor.
Also onboard the lander is a light detection and ranging (lidar) experiment provided by Russia's Space Research Institute. The instrument will detect and determine the altitude of atmospheric dust hazes and ice clouds above the lander. Inside the instrument is a small microphone, furnished by the Planetary Society, Pasadena, CA, which will record the sounds of wind gusts, blowing dust and mechanical operations onboard the spacecraft itself.
The lander is expected to operate on the surface for 60 to 90 Martian days through the planet's southern summer (a Martian day is 24 hours, 37 minutes). The mission will continue until the spacecraft can no longer protect itself from the cold and dark of lengthening nights and the return of the Martian seasonal polar frosts.
The Mars Climate Orbiter, Mars Polar Lander and Deep Space 2 missions are managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. Lockheed Martin Astronautics Inc., Denver, CO, is the agency's industrial partner for development and operation of the orbiter and lander spacecraft. JPL designed and built the Deep Space 2 microprobes. JPL is a division of the California Institute of Technology, Pasadena, CA.
For more information on the Mars Climate Orbiter and Mars Polar Lander missions, please visit our website at: