Archive for November, 2011

Mission Control to Mars: Launching the Next Mars Rover

Monday, November 28th, 2011

By Rob Manning

In the wee morning hours of Nov. 26, 2011, scientists and engineers gathered in the mission control room at NASA’s Jet Propulsion Laboratory to help launch the next Mars rover, Curiosity. The mission’s chief engineer, Rob Manning, shares the developing story from the control room as tensions and excitement for a mission eight years in the making reached all new heights.

NASA's Mars Science Laboratory spacecraft, sealed inside its payload fairing atop the United Launch Alliance Atlas V rocket
NASA’s Mars Science Laboratory spacecraft, sealed inside its payload fairing atop the United Launch Alliance Atlas V rocket, launched on Nov. 26 from Kennedy Space Center in Florida.

5:45 a.m. PST (L-01:17:00)
I drove in this morning at 4:30 a.m. As usual, I was greeted by the cheery guards at the gate along with a small family of local deer, who keep sentry over a small patch of greenery at NASA’s Jet Propulsion Laboratory.

I quickly march into JPL’s mission control area to find the first shift quietly following the prelaunch procedure in sync with the Assembly, Test and Launch Operations (ATLO) procedure. They had been on station since 1:30 a.m. I tried that procedure at last week’s launch rehearsal and found the hour a bit unpleasant. Today, I am working on the Anomaly Response Team (ART) for post-launch anomalies. This means that if all goes well, I will have little to do but cheer when NASA’s Mars Science Laboratory rover launches. I have my own console where I can monitor both the spacecraft and listen to the voice nets (there are 10 of them!).

There are about 30 people here. Usually there are not as many, but today we have two people for every subsystem: power, thermal, propulsion, systems, fault protection, attitude control and management. I can hear the JPL ATLO test conductor, Art Thompson, at NASA’s Kennedy Space Center in Florida double check that the right sequence files have been sent. One in particular has commands that tell the rover when to automatically transition into “eclipse” mode. This software mode puts the entire vehicle into the configuration needed for the period prior to separation from the Centaur. In particular this mode turns on the descent stage and cruise stage tank heaters. This timer should be set about 15 minutes after launch, which is planned for 7:02 am PST today. It is an absolute time so they have to send a new time every time we have a new launch attempt. The voice net that is the most interesting is the launch vehicle’s fueling operations. I have not heard that one before. They are more than 50 percent of the way through fueling!

It is fun to see the crowd here. No dress code, but some have come in ties, others with pink mohawks. Nice combo. Professionals all. The peanuts have already made the rounds.

6:15 a.m. (L-00:47:00)
Brian Portock, today’s flight director at JPL, just finished the launch poll of the room to see if everyone is go for transition to launch mode. This is a command to the rover that will put everything on the rover into a mode that is used for the first 15 minutes of flight. In particular, the heaters are all put into a launch and cruise configuration. We expect that the cruise stage heaters will be on more than off due to the air conditioning needed to keep the spacecraft cool (hot generators, you know).

6:29 a.m. (L-00:33:00)
Arm pyros! Once these relays are closed, they will be that way for the next 8.5 months.

6:32 a.m. (L-00:30:00)
The data rate is lowered to launch nominal to 200 bits per second. This will allow the rover’s data to flow to both the ground (via wires to the power van at the foot of the launch pad that provides power to the rover before launch) and to the launch vehicle where it will be available throughout launch (very cool). The JPL management showed up. Charles Elachi is behind me. My old friend and JPL Chief Engineer Brian Muirhead is here with his family.

6:40 a.m. (L-00:22:00)
The flight director is doing the launch poll for the team here at JPL: “All stations at JPL report go.” ATLO is going through its poll at lightening speed. All stations go. This is going fast! The weather guys report of scattered skies at 5,000 feet looks good. I am getting excited.

6:47 a.m. (L-00:15:00)
We lost the flow of data from MSL via the Atlas Space Flight Operations Center (ASOC) land lines, but they switch it to the radio path from the launch vehicle, and it starts flowing again.

7:00 a.m. (L-00:02:00)
All Quiet. Peanuts going around the room again … everyone is excited!

7:01 a.m. (L-00:01:20)
Everything is armed …

7:01 a.m. (L-00:00:30)

7:03 a.m. (L+00:01:00)

7:06 a.m. (L+00:04:00)
Fairing falls off! Wind on MSL ;)

7:07 a.m. (L+00:05:00)
Rob Zimmerman, our power systems engineer, reports power on solar arrays! 3.3 x 2 = 6. 7 amps! The spacecraft is still power-negative for a while which means that the battery is still discharging. We need more sunlight - very soon.

7:11 a.m. (L+00:09:00)
Getting intermittent data from the rover via the Centaur. So far, no computer reboots!

7:12 a.m. (L+00:10:00)
The ATLO test conductor reports that they are done building and launching MSL (hey, it took ‘em long enough! ;) ). We all cheer and smile. They are supporting the cruise team now.

7:14 a.m. (L+00:12:00)
We’ve reached the end of the first burn (MECO1). All is well. Eighteen minutes to second burn. Battery is charging at 4.3 amps for each battery — very good.

7:17 a.m. (L+00:15:00)
The eclipse-mode transition should be done; don’t know yet. Got it. The tank heaters should be on now; They are. Batteries are still charging at 95 percent state of charge (SOC).

7:35 a.m. (L+00:33:00)
Waiting for telemetry from over Africa …

7:36 a.m. (L+00:34:00)
It’s five minutes to MECO2, pushing out of Earth orbit. Heavy rover! KEEP PUSHING! Mars awaits.

7:39 a.m. (L+00:37:00)
The spacecraft is nearly out of Earth orbit, six minutes until separation from Centaur upper stage. Everyone is relaxed, but there’s not a lot of data from the rover. It still says it is in launch mode — missed the data that said eclipse.

7:42 a.m. (L+00:40:00)
MECO2. next is turn to separation attitude and spin up. Separation! We get a beautiful view of MSL spinning away from us — in the right attitude and the right direction! (› See Video)

Video: The Mars Science Laboratory spacecraft separates from the upper stage of its Atlas V launch vehicle and heads on its way to Mars.
› See video

7:53 a.m. (L+00:51:00)
We have lock from NASA’s Deed Space Network in Canberra, Australia!

8:07 a.m. (L+01:05:00)
Data-slowing coming … All looks good, batteries at 98 percent. The rover is now in cruise mode. The heaters are on and cycling as designed. The spacecraft is spinning at 2.5 rotations per minute with only 1 degree of nutation (or swaying) — that is not a lot. The Atlas and Centaur did a fantastic job! The generator is working.

8:26 a.m. (L+01:24:00)
Now let’s try the uplink (sweep). Sweep is working! We have strong signals both ways. We are getting two-way Doppler - navigation says that the frequency is just a few hertz off so we had a very nominal injection to solar orbit. We can command!

Everyone is relaxed and trying to see if there is anything that looks wrong, but so far, nothing. Everything is fine. This is weird. Our bird is on its way - it’s where it belongs. We are happy to be in a completely new mode. No more last-minute fixes (to anything but the software). We have a lot to do, but at least our bird is on its way.

Slice of History: Advanced Ocean Technology Development Platform

Wednesday, November 9th, 2011

By Julie Cooper

Each month in “Slice of History” we feature a historical photo from the JPL Archives. See more historical photos and explore the JPL Archives at

Advanced Ocean Technology Development Platform
Advanced Ocean Technology Development Platform — Photograph Number P-23298B

The Advanced Ocean Technology Development Platform (AOTDP) was developed at NASA’s Jet Propulsion Laboratory in the late 1970s by the Undersea Technology Program Office. The project applied space program instruments and systems to ocean exploration, mapping and resource assessment. This photo was taken in December 1980, after more than two months of engineering tests around Long Beach and Los Angeles harbors. The AOTDP shallow water test team included, from left to right, Sherry Wheelock, Don Hoff, Gary Bruner, Larry Broms, Curtis Tucker, Hal Holway, Garry Paine, Martin Orton and task manager Bill Gulizia.

The submersible vehicle test platform carried digital side-looking sonar for underwater imaging and a tow cable connecting the submersible to its companion surface ship, providing command, telemetry and power links. There was a shipboard control and data acquisition center to process and display the information gathered by the submersible, at rates of up to 250,000 bits per second. It was designed to descend as deep as 20,000 feet, but test tows were conducted at depths of about 600 feet. The project was funded by NASA and tests designed to improve the side-looking sonar instrument were sponsored by the National Oceanic and Atmospheric Administration (NOAA).

This post was written for “Historical Photo of the Month,” a blog by Julie Cooper of JPL’s Library and Archives Group.

Asteroid Vesta, All in the Details

Thursday, November 3rd, 2011

By Marc Rayman

As NASA’s Dawn spacecraft investigates its first target, the giant asteroid Vesta, Marc Rayman, Dawn’s chief engineer, shares a monthly update on the mission’s progress.

Image of the giant asteroid Vesta by Dawn
NASA’s Dawn spacecraft obtained this image with its framing camera on September 20, 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 673 km and the image resolution is about 66 meters per pixel. Image credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA
› Full image and caption

Dear Dawnderfuls,

Dawn has completed another wonderfully successful phase of its exploration of Vesta, studying it in unprecedented detail during the past month. From the time of its discovery more than two centuries ago until just a few months ago, this protoplanet appeared as hardly more than a fuzzy blob, an indistinct fleck in the sky. Now Dawn has mapped it with exquisite clarity, revealing a fascinatingly complex alien world.

The high altitude mapping orbit (HAMO) includes the most intensive and thorough imaging of the entire year Dawn will reside at Vesta. Spectacular as the results from survey orbit were, the observations from HAMO are significantly better. From four times closer to the surface, Dawn’s sensors provided much better views of the extraordinary surface of craters large and small, tremendous mountains, valleys, towering cliffs, ridges, smooth and flat regions, gently rolling plains, systems of extensive troughs, many clusters of smaller grooves, immense landslides, enormous boulders, materials that are unusually bright and others that are unusually dark (sometimes adjacent to each other), and myriad other dramatic and intriguing features. There is no reason to try to capture in words what visual creatures like humans can best appreciate in pictures. To see the sites, which literally are out of this world, either go to Vesta or go here.

Circling the colossus 680 kilometers (420 miles) beneath it in HAMO, the probe has spent most of its time over the illuminated side taking pictures and other scientific measurements and most of the time over the dark side beaming its precious findings back to eager Earthlings.

Dawn revolves in a polar orbit around Vesta, passing above the north pole, then traveling over the day side to the south pole, and then soaring north over the night side. Each circuit takes 12.3 hours. Meanwhile, Vesta completes a rotation on its axis every 5.3 hours. Mission planners choreographed this beautiful cosmic pas de deux by choosing the orbital parameters so that in 10 orbits, nearly every part of the lit surface would come within the camera’s field of view. (Because it is northern hemisphere winter on that world, a region around the north pole is hidden in the deep dark of night. Its appearance in Dawn’s pictures will have to wait for HAMO2.) A set of 10 orbits is known to Dawn team members (and now to you) as a mapping cycle.

Although the HAMO phase was extremely complex, it was executed almost flawlessly, following remarkably well the intricate plan worked out in great detail last year. It consisted of six mapping cycles, and they were conducted in order of their overall importance. In the first cycle, Dawn aimed its camera straight down and took pictures with all of the instrument’s color filters. In addition to showing the startling diversity of exotic features, the color images provide scientists some information about the composition of the surface materials, which display an impressive variation on this mysterious protoplanet. Cycle 1 yielded more than 2500 photos of Vesta, nearly as many as were acquired in the entire survey orbit phase. These observations were deemed so important that not only were they first, but cycle 6 was designed to acquire nearly the same data. This strategy was formulated so that if problems precluded the successful mapping in cycle 1, there would be a second chance without requiring the small and busy operations team to make new plans. As it turned out, there were only minor glitches that interfered with some of the pictures in cycle 1, but the losses were not important. Nevertheless, cycle 6 did fill in most of the missing views.

Cycles 2 through 5 were devoted to acquiring images needed to develop a topographical map. Instead of flying over the sunlit side with its camera pointed straight down, the spacecraft looked at an angle. Each direction was chosen to provide scientists the best combination of perspective and illumination to build up a three dimensional picture of the surface. Knowing the elevations of different features and the angles of slopes is essential to understanding the geological processes that shaped them.

In cycle 2, the camera constantly was directed at the terrain ahead and a little to the left of the point directly below the spacecraft. Cycle 3, in contrast, looked back and slightly to the left. Cycle 4 pointed straight ahead but by a smaller angle than in cycle 2. Cycle 5 did not look forward or backwards; it only observed the surface to the right. With the extensive stereo coverage in each of these 10-orbit mapping cycles, most of the terrain now has been photographed from enough different directions that the detailed shape of the alien landscape can be determined.

The HAMO observations constitute the most comprehensive visible mapping of Vesta for the mission. The survey orbit images were obtained from a higher altitude and so do not show as much detail. When Dawn flies down to its low altitude mapping orbit (LAMO), its primary objectives will be to measure the atomic constituents with the gamma ray and neutron detector (GRaND) and to map the gravitational field. While some images will be acquired, they will be a secondary objective. The principal resources, both for the spacecraft and for the operations team, will be devoted to the higher priority science. In addition, the probe will be too close in LAMO for its camera to collect enough pictures for a global map. The subsequent observations in HAMO2 will be designed mostly to glimpse some of the northern latitudes that are currently too dark to see.

› Continue reading Marc Rayman’s Dawn Journal