Contact the ISS
How to Call Space Station Astronauts on the Radio
A ground station contains a device capable of both transmitting and receiving radio waves near the 145 megahertz frequency. The ISS radio transmits signals at 145.80 MHz and receives signals at either 144.49 or 145.20 MHz, depending on its orbital location.
Some ISS crew members make random, unscheduled, amateur radio voice contacts with earth-bound radio amateurs, often called "hams". They can make radio contacts during their breaks, pre-sleep time and before and after mealtime. Astronauts have contacted thousands of hams around the world. The work schedules of the ISS crew dictate when they are able to operate the radios. The crew's usual waking period is 0730 - 1930 UTC. The most common times to find a crew member making casual periods are about one hour after waking and before sleeping, when they have personal time. They're usually free most of the weekend, as well. (The current crew work schedule is published on the NASA website.)
Want to talk to an astronaut in space? Thanks to the Amateur Radio on the International Space Station (ARISS) program, you may be able to. There's a ham radio on board the space station, and about 45 times a year, crew members tune in and hold Q&A sessions with groups of people (usually students) from around the world.
ISS Frequencies List
