SpaceX mission to ISS delayed by electrical problems

The six astronauts aboard the International Space Station can rest easy: Full power has been restored to the orbiting laboratory.

Electrical problems left the space station running on about 75% its normal power supply, delaying SpaceX’s latest uncrewed resupply mission to the ISS.

The rocket company was supposed to drop off a bundle of hardware and supplies this week. But the launch was called off as the crew worked to restore the station’s full power supply. The space station’s crew was not in immediate danger, NASA said in a blog post.

NASA announced Thursday that its efforts to replace a piece of failed electrical equipment were successful, the space agency said in a blog post.

SpaceX is now lined up to begin its cargo mission on Friday at 3:11 am ET — but there may be another roadblock.

Some bad weather could move from the Bahama’s to Florida’s Space Coast, where SpaceX is set to launch, according to Will Ulrich, a launch weather officer with the US Air Force 45th Space Wing. There’s a 40% chance the weather will be good enough for liftoff Friday, officials predict.

Parts of the football field-sized space station lost power on Monday, but the crew was able to keep the lights on and continue running experiments by rerouting power from other lines while they worked to restore full functionality, NASA said in a Tuesday statement. The ISS team replaced a piece of hardware that routes the power generated by solar panels all over the station. And everything was working normally again by Thursday morning.

NASA did not want SpaceX’s Dragon 1 — the spacecraft that is supposed to carry cargo on Friday — to begin its trip before power was restored becuse the spacecraft relies on a giant robotic arm attached to the ISS that latches on to the capsule as its approaches. But the power supply issues had left the robotic arm without a back-up power source, sparking safety concerns.

The power problem threw a wrench into what has otherwise become a routine mission for SpaceX. The company is one of a couple commercial businesses that NASA partners with to occasionally ferry cargo and supplies to ISS crew members. SpaceX has contracts worth billions of dollars to do so.

This upcoming resupply mission will mark SpaceX’s 17th for NASA. The uncrewed Dragon 1 capsule will carry about 5,500 pounds of luggage, including hardware that will map carbon dioxide levels in Earth’s atmosphere, a piece of equipment that could help communicate with deep-space exploration probes, and a host of science experiments.

But when SpaceX does launch, there is a separate issue that could throw another curveball into its plans: Where to land the rocket booster after launch.

SpaceX is the only company in the world that lands and reuses rocket boosters after missions to orbit, and it frequently does so. The company says reusing hardware is at the core of its plan to drastically reduce the cost of spaceflight. And the booster, the largest piece of the rocket and the part that gives it the initial thrust at liftoff, accounts for about 60% of the rocket’s cost, according to CEO Elon Musk.

The problem is that SpaceX used one of its ground pads in Florida for an April 20 test of its new Crew Dragon spacecraft. That test ended in fiery disappointment, and the site is out of order. SpaceX said the ground pad needs to be quarantined while it investigates what went wrong with the Crew Dragon test.

SpaceX has a backup plan for its upcoming mission, at least. The company can use a seaborne platform, or droneship, to serve as a landing side for its reusable rocket booster.

Typically, droneships are only used for SpaceX missions that require the rocket to travel so far out over the ocean that the booster doesn’t have enough fuel left to return safely to terra firma. That’s not the case for this mission, so the droneship will only need to travel about 20 miles off the coast.

The Crew Dragon mishap is still concerning for other reasons. That spacecraft is built to carry humans, and is a critical part of a separate, multibillion-dollar contract SpaceX has with NASA to eventually begin flying astronauts to the space station. Boeing has a similar contract. But both companies are already years behind schedule.

An investigation into what caused SpaceX’s Crew Dragon to misfire is underway. Hans Koenigsmann, SpaceX’s vice president of mission assurance, confirmed during a press briefing Thursday that the spacecraft was destroyed during the test.

It could derail plans to fly astronauts aboard the spacecraft later this year.

Correction: An earlier version of this story misspelled the name of NASA spokesperson Gary Jordan.