BY SPACEFLIGHT NOW

Follow the mission of NASA's 2001 Mars Odyssey spacecraft and the insertion maneuver to enter orbit around the Red Planet. Reload this page for the very latest on the mission.

WEDNESDAY, OCTOBER 24, 2001
1930 GMT (3:30 p.m. EDT)

In a press conference today Mars Odyssey officials reported what they have learned in the extensive data review following last night's arrival at the Red Planet and orbit insertion burn.

Flight controllers say the spacecraft is in excellent health and is in a looping orbit around Mars of 18 hours and 36 minutes.

"Odyssey flawlessly achieved last night's one-time critical event of Mars orbit insertion. Hundreds and hundreds of things had to go right, and they did," said Matt Landano, Mars Odyssey project manager at NASA's Jet Propulsion Laboratory. "We are all excited about our success and I am proud of all the members of our team."

The navigation proved to be equally precise. "We were aiming for a point 300 kilometers (186.5 miles) above Mars and we hit that point within one kilometer (.6 miles)," reports Bob Mase, the Mars Odyssey lead navigator at JPL. "Because of the excellent main engine burn, we will not need to do any more maneuvers to adjust the orbit before we begin aerobraking on Friday."

In the weeks and months ahead, the spacecraft will be literally surfing the waves of the martian atmosphere, in a process called aerobraking, which will reduce the long elliptical orbit into a shorter, 2-hour circular orbit of approximately 400 kilometers (about 250 miles) altitude.

This morning, the team turned on the electronics for the gamma ray spectrometer subsystem and began taking data with the high-energy neutron detector and the neutron spectrometer instruments. These detectors may help scientists locate water near the surface of Mars, if it exists.

On Sunday, scientists will take the first picture with the thermal emission imaging system. That image is expected to be a wide-angle view of the southern hemisphere taken when Odyssey is farthest away from Mars. The primary science mission will begin in January.

Here are some video and audio clips from today's detailed briefing for our Spaceflight Now Plus subscribers:

Video coverage for subscribers only:

   AUDIO: REPORT ON ODYSSEY'S TRAJECTORY AND ORBIT QT or RV
   AUDIO: SPACECRAFT SYSTEMS WORKED PROPERLY QT or RV
   VIDEO: PREVIEW OF AEROBRAKING MANEUVERS QT or RV
   AUDIO: OVERVIEW OF MARS ODYSSEY SCIENCE MISSION QT or RV
   VIDEO: ANIMATION OF ODYSSEY'S TREK TO MARS QT or RV
   VIDEO: ANIMATION OF ORBIT INSERTION BURN QT or RV
   MORE: COMPLETE SFN+ VIDEO INDEX

0500 GMT (1:00 a.m. EDT)

"How sweet it is."

That was the message from NASA Administrator Dan Goldin at the late-night press conference to confirm the 2001 Mars Odyssey craft had successfully entered orbit around the Red Planet, a triumph for the space agency that had lost its two previous Mars probes.

Read our full orbit insertion wrap-up story.

And here are some video and audio clips from the orbit insertion activities and the subsequent press briefing for our Spaceflight Now Plus subscribers:

Video coverage for subscribers only:

   VIDEO: CONFIRMATION THAT ENGINE FIRING UNDERWAY QT or RV
   VIDEO: CELEBRATION AFTER ODYSSEY ENTERS ORBIT QT or RV
   AUDIO: GOLDIN SAYS SUCCESS LIFTS AMERICAN SPIRIT QT or RV
   AUDIO: LANDANO SAYS ODYSSEY IN SUCCESSFUL ORBIT QT or RV
   AUDIO: GOLDIN TALKS ABOUT ACCEPTABLE FAILURES QT or RV
   MORE: COMPLETE SFN+ VIDEO INDEX

0403 GMT (12:03 a.m. EDT)

At a news conference just underway at NASA's Jet Propulsion Laboratory, officials confirm that a healthy Mars Odyssey spacecraft is in orbit around the Red Planet. Engineering data stored in the probe's flight computer is now being transmitted to Earth to give controllers insight into the operation of the spacecraft's systems during the orbit insertion burn.

Another briefing is scheduled for 1700 GMT (1 p.m. EDT; 10 a.m. PDT) Wednesday to provide more detailed information about the burn and exact orbit achieved.

0300 GMT (11:00 p.m. EDT)

Ground controllers will need some time to review data and determine the exact level of success of tonight's burn and spacecraft health. A news conference is scheduled for 0345 GMT.

0256 GMT (10:56 p.m. EDT)

Aqusition of signal right on time! The Mars Odyssey spacecraft has emerged from behind the Red Planet exactly on schedule and Earth has locked onto the probe's signal. This means that the burn has put Odyssey where it was supposed to.

The flight control team and senior managers at JPL have broke out into applause and hugs all around!

0251 GMT (10:51 p.m. EDT)

Odyssey should be reorienting itself so the high-gain antenna is pointed toward Earth. Four antennas on Earth -- two in California and two in Australia -- will be listening for the spacecraft when it passes from behind Mars in about four minutes.

0246 GMT (10:46 p.m. EDT)

The orbit insertion burn should be concluded by this time. However, confirmation of a successful burn won't be available until after the spacecraft emerges from behind the Mars in about 10 minutes.

0243 GMT (10:43 p.m. EDT)

The navigation team reports that a review of the data indicates the burn performance through the loss of signal was as expected.

0237 GMT (10:37 p.m. EDT)

Loss of signal reported. Odyssey moved behind Mars as scheduled at 0236:42 GMT. The spacecraft continues its engine firing while out of view of Earth. The burn should conclude at 0246 GMT. Earth should regain signal from Odyssey at 0256 GMT.

0235 GMT (10:35 p.m. EDT)

As expected, ground controllers have little insight into what is happening aboard the Mars Odyssey spacecraft. That can see that the engine firing is underway based on the "pitch" of the carrier signal coming from the probe. But in about two minutes, Odyssey will pass behind Mars and that signal will be lost.

0233 GMT (10:33 p.m. EDT)

After some tense minutes flight controllers have finally been able to determine that the engine ignition had occurred the spacecraft is on the proper course.

0231 GMT (10:31 p.m. EDT)

ENGINE IGNITION CONFIRMED! NASA's 2001 Mars Odyssey spacecraft has begun the planned 20-minute engine firing to enter orbit around the Red Planet. This burn must be successful in order for the probe to slow down and be captured by the Martian gravity. Otherwise, Odyssey would fly past the planet.

This Mars Orbit Insertion burn is being accomplished by the 695-Newton main engine on the spacecraft. The firing will consume about 263 kg of propellant, putting Odyssey into a highly elliptical orbit around Mars with a low point of 300 km, high point of 28,000 km with a period of 19.9 hours.

0227 GMT (10:27 p.m. EDT)

The carrier signal from Odyssey is weak as expected. Since there isn't a live stream of telemetry data coming from the spacecraft during this engine burn, flight controllers look for changes in the "pitch" or "tone" of the carrier signal to indicate a change in velocity for the spacecraft. That would then indicate the burn has started.

0227 GMT (10:27 p.m. EDT)

Flight controllers are still awaiting confirmation that the burn has started.

0225 GMT (10:25 p.m. EDT)

One minute from engine ignition.

0223 GMT (10:23 p.m. EDT)

Controllers report a pressure sensor problem has been noted. However, that should not impact tonight's engine firing.

0221 GMT (10:21 p.m. EDT)

The spacecraft is now reorienting itself to the proper attitude for the orbit insertion burn. Ignition is five minutes away.

0219 GMT (10:19 p.m. EDT)

Odyssey has switched from its higher-data rate antenna to an omni-directional antenna. The spacecraft has also suspending transmissions of data to Earth and is now sending only a carrier signal.

0212 GMT (10:12 p.m. EDT)

Pyrotechnics have been fired aboard Odyssey to open valves that permit the fuel and oxidizer to flow from storage tanks into the propellant lines to the main engine. The system now will be pressurized. Engine ignition is 14 minutes away.

0208 GMT (10:08 p.m. EDT)

The catalyst bed heaters have been activated to condition Mars Odyssey's reaction control thrusters. These thrusters will be fired to keep the spacecraft positioned properly during the upcoming main engine firing.

0200 GMT (10 p.m. EDT)

Flight controllers in Pasadena and Denver are anxiously waiting for tonight's crucial engine firing by the Mars Odyssey spacecraft, now 26 minutes away. The burn will slow the probe so Mars' gravity can capture Odyssey into the planet's orbit.

We'll update this page as events occur this evening.

TUESDAY, OCTOBER 23, 2001

This is a look at the key events for tonight's orbit insertion maneuver for NASA's 2001 Mars Odyssey spacecraft. All times are "Earth-received times" in Eastern Daylight Time.

• 7:56 p.m.: Commands are sent instructing Odyssey to fire small thrusters to "desaturate," or unload the momentum of, the spinning reaction wheels. These devices are similar to gyroscopes and are used to control the spacecraft's orientation.
  
  
• 9:59 p.m.: The flight team performs last-minute calculations of any bias in the spacecraft's heading based on accelerometer readings. This is the last opportunity to adjust any orbit insertion activities.
  
  
• 10:06 p.m.: The catalyst bed heaters, or "catbed" heaters, are turned on to prime the spacecraft's reaction control thrusters in preparation for firing.
  
  
• 10:12 p.m.: Lines to the main engine fill with propellant, and the propellant system is pressurized.
  
  
• 10:18 p.m.: Odyssey switches from its medium-gain antenna to the low-gain antenna for receipt of commands from Earth. Odyssey stops sending data to Earth and switches to sending a carrier signal only.
  
  
• 10:19 p.m.: The Deep Space Network locks on to the carrier signal from the spacecraft. Reaction wheels turn the spacecraft to its proper orientation in preparation for the engine firing.
  
  
• 10:26 p.m.: Main engine ignites to begin Mars orbit insertion.
  
  
• 10:36 p.m.: The Deep Space Network loses the spacecraft signal as Odyssey passes behind Mars.
  
  
• 10:36 p.m.: Still behind Mars and incommunicado, the spacecraft enters the darkness of Mars' shadow (i.e. a solar eclipse) for two minutes.
  
  
• 10:39 p.m.: Odyssey reaches "periapsis," the lowest point in its first orbit of Mars, at an altitude of about 328 kilo-meters (203 miles). It is still out of reach of Earth ground stations.
  
  
• 10:45 p.m.: Main engine concludes firing.
  
  
• 10:49 p.m.: Still out of touch with the Deep Space Network, Odyssey's reaction wheels turn the spacecraft to point the high-gain antenna toward Earth. Fault protection software that was turned off a day before Mars arrival is turned on again. (Fault protection software is used to help the spacecraft respond to unexpected events by directing Odyssey to stop what it's doing and point its antenna toward Earth to await further commands. Fault protection software is turned off during critical maneuvers such as Mars orbit insertion to prevent relatively small glitches from interfering.)
  
  
• 10:56 p.m.: Odyssey emerges from behind Mars from Earth's point of view; Deep Space Network antennas seek to lock on to the spacecraft's carrier signal.
  
  
• 11:00 p.m.: Odyssey's propellant and oxidizer tanks are mechanically isolated from pressurant.
  
  
• 11:01 p.m.: The spacecraft resumes transmitting data to Earth at 40 bits per second; the Deep Space Network may take several minutes to lock on to the low-rate data stream.

TUESDAY, OCTOBER 23, 2001

NASA's 2001 Mars Odyssey spacecraft completes its six-month, 285-million mile cruise to the Red Planet on Tuesday evening with a make-or-break 20-minute engine firing to slip into orbit around Mars.

"The spacecraft, ground system and flight team are ready for Mars orbit insertion," said Matthew Landano, Odyssey project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We uplinked the sequence of commands that control the orbit insertion on Oct. 15. Now we will closely monitor the spacecraft's progress as it approaches Mars and executes the orbit insertion burn."

Flight controllers will see the main engine burn begin a few seconds after 10:26 p.m. EDT (0226 GMT Wednesday). The spacecraft will pass behind the planet 10 minutes later and will be out of contact for about 20 minutes. The burn is expected to end at 10:46 p.m. EDT, but controllers will not receive confirmation until the spacecraft comes out from behind Mars and reestablishes contact with Earth at about 11 p.m.

The firing of the main engine will brake the spacecraft, slowing and curving its trajectory into an egg-shaped orbit around the planet. In the weeks and months ahead, the spacecraft will repeatedly brush against the top of the atmosphere in a process called aerobraking to reduce the long, 19-hour elliptical orbit into a shorter, 2-hour circular orbit of approximately 400 kilometers (about 250 miles) altitude desired for the mission's science data collection.

Mars Odyssey will kick off a restructured Mars science program that focuses on the search for water on the Red Planet, past and present.

"The scientific trajectory of the restructured Mars Exploration Program begins a new era of reconnaissance with the Mars Odyssey orbiter," said Jim Garvin, lead scientist for the program. "Odyssey will help identify and eventually target those places on Mars where future rovers and landers must visit to unravel the mysteries of the Red Planet."

Mars Odyssey will accomplish this primarily with two instruments, the Gamma Ray Spectrometer (GRS) and the Thermal Emission Imaging System (THEMIS). Combined, the two instruments will give planetary scientists the best maps to date of the composition of the planet's surface, including potential sources of water.

The GRS, mounted on the end of a 6-meter boom that will be deployed after Mars Odyssey enters orbit, will measure gamma rays created by the collision of cosmic radiation with the surface of Mars. Different materials gave different gamma ray "signatures" which the GRS can detect, allowing scientists to measure the elemental composition of the surface.

Included with the GRS package is a pair of neutron detectors mounted on the body of the spacecraft. These detectors measure neutrons of different speeds emitted from the surface, also through collisions with cosmic radiation. Those neutron measurements will allow scientists to measure the amount of hydrogen -- and hydrogen-bearing compounds, notably water -- in the upper meter of the Martian soil. A similar instrument was used on the Lunar Prospector spacecraft to discover water ice deposits within craters near the poles of the Moon.

Such measurements could be key to understanding how much water might exist near the surface of Mars today, either in the form of ice deposits just below the surface or as hydrated minerals. The search for such evidence -- "following the water," as NASA officials have described it -- plays a central role in the science program of the revamped Mars exploration program.

THEMIS, the other major instrument on Mars Odyssey, will also contribute to the search for water. The instrument will map the surface of the planet at 10 infrared wavelengths, which combined will allow scientists to measure the composition of the surface to abundances of 5-10 percent with a resolution of 100 meters.

The data from THEMIS will give scientists their first global maps of the mineral composition of the surface, and allow them to identify minerals that could have been created or altered by water. In addition, THEMIS observations at night could identify regions of geothermal activity on the planet's surface, including areas that could harbor hot springs of water.

In addition to its infrared imaging, THEMIS will also take images at visible light wavelengths of regions of the planet, with an emphasis on features that appear to have been formed by flowing water. Those images will be combined with the mineral composition data to help identify regions of scientific interest for future lander missions.

"For the first time at Mars we will have a spacecraft that is equipped to find evidence for present near-surface water and to map mineral deposits for past water activity," said Mars Odyssey project scientist Steve Saunders. "This mission will give us a basic understanding about the chemistry and mineralogy of the surface."

While GRS and THEMIS will provide the major Martian scientific data from the mission, data from a third instrument may help in the ultimate stage of Martian exploration. The Mars Radiation Environment Experiment (MARIE) will measure the radiation environment around the spacecraft both during the cruise to Mars and after entering orbit, studying the contributions from both the Sun and galactic cosmic rays. The data from MARIE will help scientists and engineers understand how much radiation a human would be exposed to on a manned Mars mission, and how much shielding would be needed to protect them.

Watch this page for updates during the Mars Orbit Insertion maneuver.

Read our Odyssey launch coverage.