Earth to space station: Howdy partner!

Hundreds of students willpoint high-powered LED lights skyward from a small airstrip south of Calgary to send a secret message to the International Space Station that's orbiting Earth on Saturday night.

The students will have about six minutes to send their orchestrated message as the International Space Stationdarts across the night sky more than 300 kilometres above the Earth. That's how long it takes for the orbiting spacecraft to travel from horizon to horizon.

One of the astronauts on board is Canadian Robert Thirsk, who is working on the orbiting station for six months. The message will be sent from an acreage that belongs to Soren Christiansen, Thirsk's friend and former University of Calgary engineering classmate.

"It's very supporting for him to have a bunch of people doing something that recognizes him," Christiansen said.

The event is a collaboration between the University of Calgary, students and Discovery Channel, and will result in a video to be posted on YouTube next week. The LED light panels were built specifically for the event and donated by Osram Opto Semiconductors.

At 8.30 p.m. local time Saturday, an estimated 650 students armed with the special light panels are to sendtheir choreographed message to the space station.

Calgary universitystudent Liam Nelson is organizing the volunteers and said the display will take a lot of co-ordination to pull off.

"We have to do a couple of hours rehearsal ahead of time with all the students.

"And then we're going to give them some dinner, then after that we're going to get right on it."

Nelson said the message will be a combination of words, shapes, and Morse code.

If all goes well, Thirsk will try to call the ground crew to say message received. But it won't be until late November before he can thank everyone in person.