Elon Musk, chief executive officer of Space Exploration Technologies Corp. (SpaceX) and Tesla Inc., speaks during an event at SpaceX headquarters in Hawthorne, California, U.S., on Thursday, Oct. 10, 2019.

On Tuesday, Tesla revealed in a new SEC filing some of the ways that it works with CEO Elon Musk's aerospace venture, SpaceX.

The filing shows related party transactions that included the purchase of $600,000 of Tesla car parts by SpaceX in the first quarter of 2020.

While transactions between the two firms aren't new, Tesla hasn't ever reported a bulk sale of car parts to SpaceX. There are other areas where Tesla and SpaceX sometimes work together.

SpaceX is collaborating with NASA and astronauts will drive to their launchpad in Tesla vehicles during a forthcoming (and historic) launch, for example. Astronauts Doug Hurley and Bob Behnken took a Tesla Model X ride to the launchpad during a 'dress rehearsal" for the launch in January this year, too. It's not known how many Tesla vehicles SpaceX may own or operate in its fleet.