Watch Rocket Lab launch a NASA climate change cubesat early on May 25

Rocket Lab will launch a small NASA Earth-observation satellite early Saturday morning (May 25), and you can watch the action live.

An Electron launcher is scheduled to lift off from Rocket Lab‘s New Zealand site Saturday during an hour-long window that opens at 3:15 a.m. EDT (0715 GMT; 7:15 p.m. local New Zealand time). It will carry to orbit the first of two cubesats for NASA’s PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment) climate-studying mission.

You can watch the launch live courtesy of Rocket Lab, and Space.com will air the company’s stream if, as expected, it is made available. Coverage will begin 30 minutes before the window opens.

Related: NASA’s twin spacecraft will go to the ends of the Earth to combat climate change

Rocket Lab will also launch the second PREFIRE satellite. The date for that coming liftoff has not been announced, but it will occur within three weeks of Saturday’s launch, according to the company.

Both PREFIRE satellites are 6U cubesats. The “U” stands for “unit,” a cube 4 inches (10 centimeter) on a side that’s the basic building block of cubesats. (So a 6U cubesat is the size of six such units.)

The PREFIRE cubesats will head to different 326-mile-high (525 kilometers) circular orbits above Earth. From that perch, they’ll measure how much heat is lost from our planet’s polar regions — something that has never been done systematically from orbit, according to Rocket Lab.

“Once deployed to their separate orbits, the two PREFIRE satellites will criss-cross over the Arctic and Antarctica measuring thermal infrared radiation — the same type of energy emitted from a heat lamp — that will make climate models more accurate and help predict changes caused by global warming,” Rocket Lab wrote in a mission description.

Saturday’s launch will be the 48th overall for the 59-foot-tall (18 meters) Electron, which is designed to give small satellites dedicated rides to orbit.

Rocket Lab is working to make Electron’s first stage reusable; the company has recovered boosters from the sea after multiple launches, and it’s gearing up to refly a first stage for the first time. But Saturday’s liftoff appears to be a more traditional effort; the mission press kit, which you can find here, doesn’t mention anything about rocket recovery.

Rocket Lab has launched NASA climate-studying cubesats before. The company lofted the four satellites of the agency’s TROPICS constellation, which monitors the evolution of tropical storms, over two Electron launches in May 2023.