The Great Martian Traffic Jam

For a planet that is supposedly void of life, Mars has fascinated humans more than any other planet besides Earth. Books and movies have been written imagining what the Martian surface might be like. And in spite of the fact that spacecraft that have wandered the Martian surface, and assured us that there definitely is no intelligent life, we still long to go there. That longing has three different spacecraft all heading for Mars over the next nine months. Scientists could indeed run into a bit of a Martian traffic jam!

So why is everyone headed to Mars now? Well it's a good time because Mars will be closer to Earth that it has been for a very long time, and that also makes Mars superb for viewing for the rest of us! None of the planets travel in circular orbits around the Sun, rather they are elliptical, slightly elongated circles. Mars orbit is more elliptical and Earth and this means that it's distance to Earth varies quite a bit.

When Mars is at opposition as it will be on August 28, lit is ined up with the Earth and Sun with the Earth in between,. But when both Earth and Mars are on the same side of the Sun, the distance between the two planets can vary as much as from less than 56 million km to more than 101 million km. This year, we are heading for a very close approach, closer than any in our lifetime. And that means it's a great time to launch spacecraft to the red planet. Everyone, it seems, took notice.

NASA's Mars Odyssey spacecraft is already orbiting Mars and has returned a tremendous amount of data, not the least of which has been data to choose suitable landing sites for the missions to come. First to arrive at Mars will be the Mars Express from the European Space Agancy (ESA.) Mars Express will put a lander on Mars sometime in December. There have been a few launch delays already but the spacecraft is expected, as the rest are, to launch in June.

The British led Beagle 2 Martian lander will search for signs of past or present life on Mars. Beagle 2 is equipped with a drill, inspired by a dentist, to drill into the surface deeper than any previous spacecraft. Beagle 2 is due to land in a region called Isidis Planitia, north of the Martian equator.

Also using the June launch window, NASA will be launching two spacecraft to Mars, both with rovers that will explore the surface. These two are expected to arrive at Mars in January 2004.

And finally, Japan is using that same June launch window to launch its Martian Orbiter, Nozomi. This orbiter should arrive at Mars in December.

So what's the big problem? We could end up in a traffic jam between the Mars Express and NASA. Mars Express mission controllers struck a deal with Nasa to borrow our Mars Odyssey for Beagle 2 while the European orbiter was busy delivering data from its own observations.

Mars Express had originally planned to land earlier so there would not have been a problem, but delays have everyone coming together at once. Somehow, Mars Odyssey will have to juggle relaying signals back to Earth for both NASA and the ESA.

It would be difficult to communicate with two spacecraft on the surface. This could be a bit of a problem because the Mars Rovers depend on guidance from controllers on Earth. Fortunately NASA has enough of a heads up to plan how to work with all three spacecraft.

The Great Martian Traffic Jam

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