When the space shuttle Challenger exploded on Jan. 28, 1986, it shook the space exploration industry to its core. Ever since that flight, two Dallas, Texas, families have sent roses to NASA's mission control in Houston every time an astronaut is about to head into space. On Tuesday, another bouquet arrived.
The families always include a rose of a similar color for each astronaut about to take off, as well as a single white rose in remembrance of everyone who has died in the name of space exploration.
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NASA didn't immediately respond to a request for some more information about the families who send the roses, but in the video below, NASA public affairs officer Josh Byerly calls them the Murphy and Shelton families. They've been shipping roses to Houston before every flight since the STS-26 shuttle launch in 1988.

“The crews of Challenger and Columbia and Apollo 1 and everyone else are remembered each and every time these bouquets arrive here in mission control," Byerly said in the video, referring to the astronauts who died in those missions.
Three red roses arrived this time, one each for astronauts Steve Swanson, Oleg Artemyev and Alexander Skvortsov, all of whom will take off from inside Soyuz 38 on March 25, from Baikonur Cosmodrome, Kazakhstan. From there, they'll head to the International Space Station.
“We’re big on tradition here at NASA," Byerly said. "And we’re very happy this tradition continues."
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