James Doohan — the beloved "Scotty" actor who died on July 20 — will be memorialized with a special spaceflight in December, and tributes surrounding that event will allow fans to participate both in-person and on-line.

As previously reported, it was Doohan's wish that a portion of his cremated remains be shot into space, in similar fashion to Gene Roddenberry in 1997. The "Memorial Spaceflight" service is conducted by Space Services Inc. (SSI) based in Houston, Texas, and the flight containing Doohan's ashes has been cleared for a launch window of December 6-12. It will take place at Vandenberg Air Force Base in Lompoc, California (on the coast about two hours north of Los Angeles).

A public memorial for Doohan is being planned in Lompoc, to be scheduled one day prior to the launch, plus a launch viewing party will be arranged. Details are still in flux, so we will post updates as information is confirmed.

In the meantime, though, fans have an opportunity to participate in the launch even if they can't be there in person. SSI has set up a forum where users can write tribute messages to Doohan. Those messages will be recorded onto a CD which will become part of the payload on the flight.

To compose a tribute to Doohan that will be sent into space, visit this Web page: Tribute to James Doohan

Messages will be accepted through November 15, 2005. There is a 500-character maximum.

The tribute page contains a message from Wende Doohan, the actor's widow, who writes in part:

"Jimmy absolutely adored playing the role of Scotty on Star Trek. He promoted space exploration and travel wherever he went. He would have given almost anything to be able to actually go into space. When asked if he would ever ride the Space Shuttle, with a twinkle in his eye he replied, 'In a heartbeat!!'

"He finally gets his wish, through the efforts of Space Services, Inc., as his remains will be launched on their Falcon I rocket."

Once you have submitted your tribute, you will be given the option to purchase a Launch Certificate, which is a personalized official document displaying your name and message and certifying that they will be included on the spaceflight. You can receive the certificate by e-mail, or have a physical document mailed to you with or without a frame, at different price points.

Doohan's ashes will be part of the "Explorers Flight," the name of this specific mission, which will also contain the remains at least 160 other participants, including John Meredyth Lucas, a writer/director/producer on the Original Series (related story). This is the sixth such Memorial Spaceflight by SSI, their inaugural being the one with Roddenberry (called the "Founders Flight" which launched April 21, 1997).

The Memorial Spaceflight only utilizes a "symbolic portion" of a participant's cremated remains — in Doohan's case, seven grams.

"We're not what's called 'final disposition' — we don't launch all of the ashes, of which there would be five to seven pounds, because that would be way too expensive," said Charles M. Chafer, CEO of SSI. "We're what's called 'memorialization,' which is a very big trend in funeral service provision right now."

Except for the portion set aside for the spaceflight, Doohan's ashes were scattered over Puget Sound in Washington, according to Steven Stevens, Doohan's long-time agent and family friend.

Each Memorial Spaceflight is actually considered "secondary payload" to a commercial or government launch. "All these rockets have more lift capability than the primary satellites that they're putting into orbit. So we pay to hitch a ride as secondary capacity. It's a very simple payload," Chafer said. The Explorers Flight will be attached to a Falcon I rocket carrying a tactical communications satellite.

Chafer explained that the flight module containing the vials of ashes — and the CD with the tribute messages — will be attached to the "avionics platform" of the Falcon rocket, which ejects the satellite, then stays in orbit at more-or-less the same altitude as the satellite. Ultimately the platform with the module will de-orbit, and burn up completely upon re-entry.

"In our marketing material we say, 'Blazing like a shooting star in final tribute.' It really is very much like that — it's a man-made meteorite, an ashes-to-ashes service that's environmentally benign," Chafer said.

The orbital life of the module can vary from a few years to a few hundred years, depending on the altitude and trajectory of the satellite it launches with. The Roddenberry module de-orbited after about seven years; Chafer estimates the Doohan module should last roughly 10 years.

We originally reported that Doohan's flight might take place in September, but delays in other missions at Vandenberg have pushed back the Falcon I countdown. In fact, the December launch window is subject to the successful lift-off of a classified government spacecraft in November. Assuming December 6 remains the target launch date, there are no guarantees it will take place then, due to technical considerations and weather factors. (If you follow Space Shuttle missions, you know how this can be!) If the target date holds firm, the memorial service in Lompoc will probably be scheduled for Monday, December 5 — but again, this will not be confirmed until sometime in November.

Stay tuned to STARTREK.COM for updates, and also visit the SSI sites for more information; several links appear below. (Take a chance to click around their site, because there is a lot of fascinating material!)