MSL crime scene

A “crime scene” image from HiRISE camera on MRO of the Curiosity landing site, showing the positions of the lander, skycrane, backshell and parachute, and heat shield. (credit: NASA/JPL/Univ. of Arizona)

More than 36 hours after landing in Gale Crater on Mars, NASA’s Curiosity rover is largely in good health and is returning new images, project officials said Tuesday morning.

“Curiosity’s still healthy, still in surface nominal mode, and still in great shape,” said mission manager Mike Watkins during a press conference at JPL Tuesday morning, after the rover had completed its activities on “Sol 1”, its first full day on the surface. The team has encountered a few minor issues as it checks out the rover, including one with the high gain antenna, which did not point as precisely to Earth as desired when it was deployed during the day. “We have a correction for that bias, and we’re going to send it up with our next command load and establish direct to Earth communications” by tomorrow, he said.

At the press conference NASA also released an image of the landing site taken by the High Resolution Imaging Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter spacecraft. The image clearly showed Curiosity as well as its heatshield, backshell and parachute, and skycrane. “This is what we call the crime scene image,” said HiRISE scientist Sarah Milkovich. The skycrane and backshell/parachute each landed about 600-650 meters away from Curiosity, although in different directions; the heat shield is about 1,200 meters from the rover in another direction.

A puff of dust seen in one of the first rear-facing Hazcam images taken by Curiosity after landing is in the same direction as the skycrane, suggesting that Hazcam might have seen the plume of dust created by the skycrane’s impact. “What precisely we saw in those images, I think the team has to talk about it and have to mull that over,” she said. “I don’t think we can rule it out,” Watkins added. He later said that once Curiosity extends its mast, the cameras at the top of the mast should be high enough to see the skycrane crash site over the flat terrain.

NASA also released the first image taken by the Mars Hand Lens Imager (MAHLI) camera on Curiosity, which is mounted on a robotic arm currently stowed; the camera, in that orientation, is facing north. The image was clouded somewhat by dust on its transparent cover, and was primarily intended as a focus test for the camera, but is the first color image taken by the rover since landing.

It was a particularly beautiful picture for MALHI principal investigator Ken Edgett of Malin Space Science Systems (MSSS), who at times was a little choked up talking about the image and his reaction. “I waited a long time for this,” he said. MSSS also provided the MARDI camera that provided images of the descent released Monday. “We built four of the color cameras on this rover we now know that [at least] two of them are working. It’s been a long journey and it’s been really awesome, that’s all I can say.”

MSL team raises arms

MSL project officials and others, including White House science advisor John Holdren (far left) and NASA administrator Charles Bolden (second from left) celebrate at the post-landing press conference. (credit: J. Foust)

As planned prior to the landing, NASA held a press conference at JPL at 11:15 pm PDT, about 45 minutes after the word came that Curiosity had set down on the surface of Mars in a landing as close to textbook as was possible with a landing system never before used. What the event was, in reality, was a party and a pep rally: a celebration and expression of relief that all went well.

“Needless to say, there is a lot of excitement in this room,” JPL director Charles Elachi said after a parade of MSL team members marched through the auditorium at the press site, high-fiving and hugging each other and the officials on the stage with cheers from the audience (including some members of the press who, for the evening, suspended the old journalist’s advice of no cheering in the press box.)

When the team did get to specifics, there was not too much to share, given the rover had landed on Mars just an hour earlier with a limited bit of telemetry relayed to Earth from Mars Odyssey. “It looked extremely clean,” Adam Steltzner, entry, descent, and landing (EDL) team lead said. Conditions at the landing site were benign and the spacecraft’s navigation error was “remarkably good”. The spacecraft landed with 140 kilograms of propellant to spare, our of an original supply of 400 kilograms.

Such specifics were in short supply in an event that was more celebratory. “Landing the Mars Science Laboratory rover Curiosity on the surface of the Red Planet was, by any measure, the most challenging mission ever attempted in the history of robotic planetary exploration,” White House science advisor John Holdren said. “And if anybody has been harboring doubts about the status of US leadership in space, well, there’s a one-ton, automobile-sized piece of American ingenuity sitting on the surface of Mars right now.”

“I can also think about the Olympics,” Elachi said. “Here we had our team which went to the Olympics. We were not sure we were going to win, but this team came back with the gold.”

Steltzner, at one point, pointed to the screen displaying one of the Hazcam images returned by Curiosity. “That picture says it all for me.”

At JPL right about now—an hour before landing—the flight controllers for MSL are engaging in an important step. Eating peanuts. As collectSPACE explains, it’s a tradition that dates back to early days at JPL, when a Ranger mission to the Moon finally succeeded after several previous had failed. Peanuts were served for that successful mission, and have ever since at JPL for launches and other key mission events.

It’s not the only tradition, or idiosyncrasy, that the MSL mission team has. At a press briefing this morning, MSL mission manager Brian Portock said that one of the team’s engineers, Matt Lenda, had grown a “playoff beard” like hockey players do during the Stanley Cup playoffs. Another, Nagin Cox, is holding on to two “trinkets” (worry beads) all day long, as she has done for past landings.

A third engineer has, well, let Portock explain: “He basically comes up with a unique hairstyle,” he said. The one he is sporting today is called “the Stars and Stripes”: “he’s got what you would call more of a mohawk, he’s got some red and blue on the top, and stars on the sides.”

Does this mean that some of the best engineers in the country–=if not the world—are superstitious? Not necessarily. “All those things work to keep people calm, kind of keep the mood light,” he said, “and also result in some good luck for Curiosity.”

EDL for Dummies

Cover of a handout about MSL’s Entry, Descent, and Landing (EDL) system at the JPL media site.

As MSL prepares for entry, descent, and landing (EDL), a quick overview may be in order of this complicated, critical, but brief phase of the mission. (How complicated? The above is the cover of a handout at the JPL media site that explains EDL in almost a children’s book like fashion, with lots of images and brief snippets of text.) The JPL website has far more detailed information about EDL, but the major phases are:

Guided Entry: Ten minutes before entry the spacecraft jettisons its cruise stage, and shortly thereafter fires thrusters to halt the spin it had during cruise. Before entry the spacecraft also jettisons two solid-tungsten weights, called “cruise balance mass de- vices”, weighing 75 kilograms each. These weights are designed to shift the center of the mass for entry, so that it generates lift during its passage through the upper atmosphere. (The weights—which have no other purpose—have raised a few eyebrows among the media, as a seemingly unsophisticated measure for a high-tech spacecraft.)

In the atmosphere the spacecraft fires thrusters to correct errors in trajectory (hence the name “guided entry”) and performs S-turns. During this phase the spacecraft experiences g-forces of 10–11g (and possibly up to 15g). The spacecraft’s speed slows from 5,900 meters per second to just over 400 m/s.

Parachute Descent: At an altitude of 11 kilometers, and 254 seconds after entry, MSL deploys its one large parachute. (Just before doing this, it ejects another set of six 25-kilogram tungsten weights to rebalance the spacecraft.) Twenty-four seconds after parachute deployment the heat shield, no longer needed, is ejected.

Powered Descent: The spacecraft is under parachute for only about 110 seconds, at which point the backshell, including the parachute, is ejected. Eight engines then fire with the spacecraft 1.6 kilometers above the surface, slowing it down from 80 m/s to about 0.75 m/s.

Skycrane: The above steps, other than the guided aspects of entry, are similar to previous missions. The Skycrane shatters any similarities from here on out. Four of the eight engines shut down, and the rover begins to descent from the skycrane stage, connected by a bridle and data cable. This lowers the rover about 20 meters to the surface, at which time the bridle and cables disconnect, and the skycrane flies away to crash a safe distance (at least 150 meters) away.

Voila! Curiosity is on Mars. Simple, isn’t it? It does seem complex, but project officials insist that it’s better—or at least less complicated—than alternative approaches. “It looks a little bit crazy,” MSL EDL lead Adam Steltzner said Thursday, “but I promise you it is the least crazy of the methods you could use, and we’ve become quite fond of it.”

NASA has released a list of “VIP attendees” who will be at JPL for the MSL landing tonight. It’s an… eclectic list, one that looks a little closer to a lineup for a season of Dancing with the Stars or some other B-list celebrity show. But at least they’re (presumably) genuinely interested in this. Some of the more famous attendees are:

  • Wil Wheaton
  • June Lockhart
  • Nichelle Nichols
  • Alex Trebek
  • Seth Green
  • Morgan Freeman
  • Angie Dickinson

Note that in the handout provided by JPL, Nichols is identified as “Original O’Hura Star Trek”. Evidently this list was not put together by a Trek fan who knows how to spell “Uhura”.

Congressman Adam Schiff (D-CA), whose current district includes JPL and Pasadena, has been a strong advocate for NASA’s planetary science program and, specifically, Mars exploration. On Saturday, he reiterated his desire to see to reverse cuts to those programs while also pushing for better goals for the nation’s space program.

“We have too long drifted without a strategic vision for space that can survive changes of administration as well as congressional appropriations cycles,” Schiff told attendees of the International Mars Society Convention in Pasadena. “Now, as we prepare to celebrate Curiosity’s arrival on Mars, we face the urgent need to set new goals and reinvigorate the space program.”

Schiff said he believes a logical long-term goal for NASA’s exploration efforts is Mars. He said he thinks the Mars Program Planning Group, commissioned by NASA earlier this year to review NASA’s Mars strategy, will recommend a path that calls for a human landing on Mars by the 2030s, a decade before a sample return mission. He called on attendees to petition their congressional representatives “for an increase in NASA’s budget as well as a national commitment to lead an effort to put humans on Mars by a date certain. Without persistence and clarity, we will continue to drift.”

Taking a more tactical approach, Schiff asked convention attendees to continue efforts to restore NASA’s planetary science budget, which have met with some success in the reduced cuts in the appropriations bills working through the House and Senate. “We still have a long way to go, and it is my hope that as we go to conference—if we go to conference—we can increase those numbers further,” he said. He warned, though, that the recent deal for a six-month continuing resolution could include some across-the-board budget cuts. “The impact on Mars will depend on how NASA allocates funds in its operating plans,” which in turn depends on guidance it receives from OMB.

“The immediate future is murky, and we need your help,” he said, suggesting that NASA was surprised by the reaction to the planned cuts since their announcement in February. “The only thing that has rescued us from the severity of what the administration proposed was the fact that planetary scientists like you have been making their voices heard and loudly,” he said. (Most of the audience of the Mars Society conference are better classified as enthusiasts and activists than as scientists, though.) “And I think frankly it has astounded the administration that you have spoken with such boldness and clarity.”

Schiff said he believes Mars was targeted for cuts because the administration thought there would be, at best, a muted reaction and little opposition. “They have been astounded by the fury of the pushback, and that is the only thing that has saved us so far.”