A SpaceX supply ship rocketed toward the International Space Station on Friday, setting the stage for an Easter morning delivery today and urgent spacewalking repairs later in the week.
Following its midday launch through cloudy skies, the Dragon cargo carrier was shown drifting away in the blackness of space, against the blue backdrop of Earth.
It is transporting 2.3 tonnes of goods, including a new spacesuit, spacesuit replacement parts, much-needed food, legs for a NASA robot, a bevy of mating flies and germs gathered from sports arenas and historic sites across the US.
Neither NASA nor SpaceX packed any Easter goodies, but the families of the six astronauts sent private care packages.
“It will be a surprise for all of us when they open the hatch,” NASA human exploration chief Bill Gerstenmaier said.
The Dragon is scheduled to reach the orbiting lab today. That pushes urgent spacewalking repairs to Wednesday; NASA wants a bad backup computer replaced before something else breaks.
This was the second launch attempt this week for SpaceX after a month’s delay.
On Monday, NASA’s commercial supplier was foiled by a leaky rocket valve. The valve was replaced, and the company aimed for a Friday liftoff despite a dismal forecast. Storms cleared out of Cape Canaveral just in time.
SpaceX’s billionaire chief executive officer, Elon Musk, was delighted with the successful launch for NASA, the client.
“This was a happy day,” he told reporters from company headquarters in Hawthorne, California.
On Friday last week, a critical backup computer failed outside the space station, and NASA considered postponing the SpaceX flight. The primary computer is working fine, but numerous systems would be seriously compromised if it broke too. A double failure also would hinder visits by the Dragon and other vessels.
“It’s imperative that we maintain” backups for these external command-routing computer boxes, also called multiplexer-demultiplexers, or MDMs, flight director Brian Smith said on Friday. “Right now, we don’t have that.”
NASA decided late this week to use the gasket-like material already on board the space station for the repair, instead of waiting for the Dragon and the new, precision-cut material that NASA rushed onboard for the computer swap. Astronauts trimmed their own thermal material on Friday to fit the bottom of the replacement computer and inserted a fresh circuit card.
The space station’s crew watched the launch via a live TV hookup; the outpost was soaring 418km above Turkey at the time of ignition. Video beamed down from Dragon showed the solar wings unfurling.
The shipment is close to five weeks late. Initially set for the middle of March, the launch was delayed by extra prepping, then damage to a US Air Force radar and, finally on Monday, the rocket leak.
Earlier, as the countdown entered its final few hours, NASA’s space station program manager Mike Suffredini said an investigation continues into the reason for last year’s spacesuit failure. The helmet worn by an Italian astronaut filled with water from the suit’s cooling system, and he nearly drowned during a spacewalk.
Routine US spacewalks are on hold until engineers are certain what caused the water leak. The upcoming spacewalk by the two Americans on board is considered an exception because of its urgent nature; it will include no unnecessary tasks, just the 2.5-hour computer swap.