Getting to Mars in Four Years: Part 12

November 5, 2003

From the science diaries of Cornell’s Steve Squyres

The Martian Chronicles, a multipart series, show the inside story of what it is like to join in a four-year space mission, in preparation for the dramatic landing sequence planned for January 2004. This is “Part 12: Flying Sorts.”

Astrobiology Magazine — Three spacecrafts are now hurtling toward the Red Planet to look for evidence that it might once have been wet enough to sustain life.

Orbital projections of where Europe’s Mars Express and the two NASA Mars Exploration Rovers (MER) are right now, can be continuously monitored over their half-year journeys. Experiments performed by the MERs will help to determine whether water might have once existed in volume on the red planet.

The two Mars Exploration Rovers are targeting what imagery indicates might have been ancient dry lake beds and other geologically interesting sites in early 2004.

The Martian Chronicles series gives an inside view of what it takes for scientists to deliver a complex mars mission. The journal entries are from Cornell’s Steve Squyres, the Principal Investigator for the Mars Exploration Rovers’ scientific package called Athena.

The chronicles begin sequentially from the beginning of July 1999, four years before launch, and will culminate in the dramatic landing of the twin rovers on Mars in January 2004. The expected mission time roaming the red planet is ninety days, from January to April.

As Spirit and Opportunity speed toward Mars, more than three hundred scientists and engineers here on Earth will learn how to act in unison to master the art of commanding two very complex robots to do science on another world.

The chronicles include an insider’s view of hardware tests and site selection to problem solving and science planning on the surface of Mars.

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September 27, 2003

Well, we survived the latest operations readiness test. It wasn’t easy. As I mentioned last week, this test was focused mostly on the period we call “Impact Through Egress”.

This is the period of time that begins when the lander comes to rest, and that ends when we’ve got six wheels in the dirt. The test went amazingly well, all things considered.

Impact Through Egress is one of the most complicated parts of the mission. The rover lands in a tightly folded-up configuration, and over a period of several days it has to unfold, take a look around, stand up, and find its way off the lander and down onto the martian surface.

We did all of that in this test, and we successfully drove the rover off the lander right on schedule.

Of course, this was an easy test compared to what’s to come. At this point we’re just trying to get all the basics down, so the test conductors didn’t throw too many nasty surprises our way. (There were several nasty-looking rocks right in front of the rover that we had to find a way around, though.) Future tests promise to be trickier. And who knows what the actual landings on Mars will bring.

October 4, 2003

Out of the frying pan and into the fire. It feels like we just finished our last Operations Readiness Test, and now it’s time to start the next one. This one is going to be a killer.

Every other test that we’ve done (and every other test that we’re going to do) involves running just one rover at a time. But once we get to Mars we’re going to have to be able to operate both Spirt and Opportunity simultaneously. So in this test, we’re going to try running two rovers at once.

We’ve got all the hardware we’ll need, and we’ve got enough people. The question is whether or not it’ll all work when we try to make it happen. We’ll find out real soon. The test starts next Monday and runs for two weeks…

October 18, 2003

If it’s 3:00 AM in Los Angeles, what time is it at Gusev Crater? That’s the kind of problem we’re wrestling with this week. We’re into the fourth martian day of our latest Operations Readiness Test.

In this test we’re simulating the process of landing the Opportunity rover at Meridiani Planum at the same time that we’re operating the Spirit rover at Gusev crater.

Both rovers operate on Mars time, of course, and the martian day is 24 hours and 39 minutes long. That’s bad enough, but it gets worse. The two landing sites are in two different locations on Mars, and the local martian time at the two sites is completely different.

So, for example…

Right now, as I type this, it’s 3:00 AM at the Jet Propulsion Laboratory. It’s 4:35 AM in Gusev crater, and it’s 4:33 PM at Meridiani Planum. At 3:00 AM Pacific time tomorrow it’ll be about 3:56 AM in Gusev crater, and about 3:54 PM at Meridiani Planum. And so forth.

It gets really confusing.

Anyway, the test is going really well. We’ve had a few hiccups, most of them because this time the people running the test have begun introducing some anomalies… little challenges (and some big challenges) of the sort that we could encounter in flight. Overall, though, it’s going very well. I just wish we didn’t have to keep such strange hours…

October 25, 2003

Is there life on Mars? Could humans build a new off-Earth settlement on the red planet? Like the Earth’s little brother, Mars has long fascinated sky-watchers. NASA’s new plans for exploration of Mars include the Athena Payload: instruments and tools for a Mars rover.

Equipped with the Athena Payload, the twin rovers of NASA’s Mars Exploration Rover project will be robotic field geologists, exploring Mars’ climate history and searching for signs of water and life. So suit up, strap in, and prepare to blast off with Athena: roving soon on a planet near you.

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Related Articles:

Getting to Mars in Four Years: Part 11

Getting to Mars in Four Years: Part 10

Getting to Mars in Four Years: Part 9

Getting to Mars in Four Years: Part 8

Getting to Mars in Four Years: Part 7

Getting to Mars in Four Years: Part 6

Getting to Mars in Four Years: Part 5

Getting to Mars in Four Years: Part 4

Getting to Mars in Four Years: Part 3

Getting to Mars in Four Years: Part 2