SEDSAT-1 (also known as SEDSAT-OSCAR 33) is a U.S. amateur radio satellite built by students and developed at the University of Alabama in Huntsville (UAH).

It was launched into a low Earth orbit on October 24, 1998 as a Secondary payload with the Deep Space 1 spacecraft using a Delta II rocket at Cape Canaveral Air Force Station, Florida, USA.

The satellite was to be built by the partnership between NASA's Marshall Space Flight Center and UAH with the primary objective of testing a newly developed small expendable deployer system developed for NASA's Space Shuttle, while allowing the students to add instrumentation to complete secondary missions after the primary data regarding the deployer's tether system had been captured.

[3] After the Tethered Satellite System (TSS-1R) experienced a failure resulting in the ignition of a strong electrical discharge shortly after being deployed from the Space Shuttle Columbia in 1996, the small expendable deployer system was subject to a Space Shuttle safety review that resulted in extensive design and requirements changes.

[6] To this end, the satellite carries two cameras as part of the SEASIS (SEDS, earth, atmosphere, and space imaging system) instrument.