Space Litter

Littering the galactic highway and a curious International Space Station (ISS) “tilt” phenomenon were among topics ISS Expedition 10 Commander Leroy Chiao, KE5BRW, addressed in a ham radio contact with Bentley School in Oakland, California.

The February 28 QSO with NA1SS was arranged by the Amateur Radio on the International Space Station (ARISS) program. Chiao opened the contact by greeting Bentley’s students and teachers as well as his sister Sandy, who visited the school for the event.

One Bentley youngster worried that space would becoming as polluted with trash as Earth. Chiao acknowledged that rubbish is thrown from the ISS “every now and then,” and even garbage went overboard from the now-defunct Russian Mir space station. But he assured the youngster that tossing trash into space can be an acceptable disposal method.

“That’s really not as big of a problem as you might think, because what happens is that over the course of a few days, the orbit decays, and it burns up in the atmosphere, so it’s really not a long-term problem,” Chiao explained. “But we do have to be careful to throw things off in the proper direction and at the right speed so that it won’t come back and hit us.”

ISS crews also dispose of trash and unneeded items by stowing them in Progress supply rockets after they’ve unloaded the cargo, then sending the vehicles into Earth’s atmosphere where they incinerate.

Responding to other questions, Chiao told the students that the ISS can accommodate a maximum crew of six or seven people, although the current crew increment is just two–Russian Cosmonaut Salizhan Sharipov and himself. He said the ISS now weighs 200 tons, and it will tip the scales at more than 250 tons–Earth weight–when it’s finally completed in a few years.

Another youngster said he and his schoolmates had read that the ISS tilts when the astronauts go on space walks. He asked if Chiao knew why this happened.

“That is kind of a mystery,” the astronaut answered. “We’re not really sure why during some of the space walks we do–including the one that Salizhan and I took a few weeks ago–the space station ended up tilting a little bit and we believe it’s because of the forces we’re putting into the station while we’re working.”

Chiao said speculation is that when the crew members are outside the ISS holding onto handrails, every time they turn bolts or have to do something that applies some force on the spacecraft, it causes a physical reaction by “tilting” the ISS.

Chiao said he views the current ISS missions as a “stepping stone” to future, longer space missions to Mars and beyond, and he expressed the hope that one of the Bentley Students could be on a future deep-space mission. In all, students got in 15 questions before the ISS went out of radio range.

Handling Earth-station duties for the event was Nancy Rocheleau, WH6PN, at Sacred Hearts Academy in Honolulu, Hawaii. Teleconferencing was compliments of MCI. Contact audio went out to some 80 stations via EchoLink.

Teacher Carol Roach coordinated the students at Bentley School, while Kerry Banke, N6IZW, mentored the contact and Will Marchant, KC6ROL, served as the moderator. ARISS is an international educational outreach with US participation by ARRL, AMSAT and NASA.