Humans may not be able to travel to Mars yet, but we our names can.

The Planetary Society, co-founded by the legendary Carl Sagan, has assembled a list of 250,000 names on a DVD that is now attached to NASA’s Phoenix Mars Lander, set to touch down on the red planet later today.

The DVD, entitled “Visions of Mars,” also features images of Mars from both pop culture (for example, Marvin the Martian) and science, a collections of stories and other works about Mars, Orson Welles’ famous “War of the Worlds” radio broadcast, and greetings to future human explorers to Mars from several people, including Sagan.

Sagan cites the many reasons that the humans listening to him in the future might be there, from impending catastrophe, to simple curiosity, adding that whatever the reason is that they are there, “I wish I was with you.”

The DVD is intended as something of a time capsule from Earth on all things Mars related to let future generations of humans know how the red planet has inspired both science and science fiction. Stories from Isaac Asimov, Ray Bradbury and Arthur C. Clarke are included on the disk to show the “dance” between science and science fiction, as Sagan says in his greeting on the disk.

The disk was originally strapped to Russia’s Mars ‘96 spacecraft, which failed shortly after launch. Planetary Society members updated the DVD for the Phoenix mission. They also sent disks with names up on the two Mars Exploration Rovers, Spirit and Opportunity, which are still scuttling around the Martian surface.

If Phoenix makes it safely to the surface of Mars, it will use its stereo camera to image and check its systems. These pictures could show the disk attached to the craft. (The disk is made of a hardy silica glass and has been tested to withstand the vibrations of travel and entry, as well as weathering from wind-blown dust and sand on Mars.)

For those who want to catch a live showing of the Phoenix landing, The Planetary Society is also holding a series of events in cities around the country that will show the mission control live on a big screen. The main event, here in Pasadena (called Planetfest ‘08) that will include speakers such as Bill Nye the Science Guy, Ray Bradbury, and Phoenix principal investigator Peter Smith. You can find a list of cities with events here.

Whether the Society’s disk will be recovered in a matter of decades or centuries is a matter of debate amongst Planetary Society members. One member is betting on the later, and says that he hopes it never comes back to Earth.