SpaceX Dragon Cargo Ship Poised for Historic Relaunch to Space Station

SpaceX’s Dragon at the ISS, September 2014
SpaceX’s robotic Dragon capsule is seen docked to the International Space Station shortly after arriving on Sept. 23, 2014. This same Dragon is poised to launch to the orbiting lab again on June 1, 2017. (Image credit: NASA)

CAPE CANAVERAL, Fla. — A SpaceX Falcon 9 rocket is being prepared for launch Thursday (June 1) to deliver nearly 3 tons of equipment, supplies and science experiments to the International Space Station (ISS).

SpaceX aims to kick off its seventh mission of the year at 5:55 p.m. EDT (2155 GMT) when the nine Merlin engines powering the Falcon 9's first stage ignite, catapulting the booster off from launch pad 39A at NASA’s Kennedy Space Center here on Florida's Space Coast. You can watch it live here at, courtesy of SpaceX.

Perched on top of the 23-story-tall rocket will be the company’s first Dragon cargo ship to make a return flight into orbit. The capsule was refurbished after a September 2014 ISS cargo run. [How SpaceX's Dragon Space Capsule Works (Infographic)]

SpaceX on March 30 relaunched the first stage of a Falcon 9 rocket for the first time. A second previously flown booster is earmarked for launch on June 15 to deliver a commercial communications satellite into orbit for BulgariaSat.

The inspection processes SpaceX has developed to make sure its boosters and capsules are safe for reflight are similar, though Dragon’s splashdown in the ocean raises some additional issues, said Hans Koenigsmann, SpaceX vice president for mission assurance,

"You need to be inspecting for corrosion very carefully," Koenigsmann told

SpaceX declined to say how much money it was saving by reflying the spacecraft, and if any of the savings were passed on to NASA.

Reusing hardware is a key component of company founder and chief executive Elon Musk’s goal to slash the cost of space travel so that people can one day live and work on Mars.

SpaceX will attempt to return the Falcon 9 first stage that's flying Thursday to a landing pad at nearby Cape Canaveral Air Force Station so that it, too, can be reflown.

The company so far has landed 10 Falcon first stages, including four touchdowns on the ground near the launch site and six on a drone barge at sea.

Thursday’s flight is SpaceX’s 11th station resupply flight under a 20-flight contract with NASA worth up to $3.1 billion.

Experiments flying aboard Dragon include an observatory to study the extremely dense stellar corpses known as neutron stars; 40 mice that will be used to test a bone-growth drug; and thousands of fruit flies for a study on how microgravity changes the heart.

The neutron-star telescope also includes a novel experiment to use fast-rotating neutron stars, known as pulsars, as a navigation system for future spacecraft.

If the Falcon 9 launches as planned on Thursday, the Dragon cargo ship would reach the station, which orbits about 250 miles (400 kilometers) above Earth, on Sunday (June 4).

Irene Klotz can be reached on Twitter at @free_space. Follow us @Spacedotcom, Facebook or Google+. Originally published on

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Irene Klotz
Contributing Writer

Irene Klotz is a founding member and long-time contributor to She concurrently spent 25 years as a wire service reporter and freelance writer, specializing in space exploration, planetary science, astronomy and the search for life beyond Earth. A graduate of Northwestern University, Irene currently serves as Space Editor for Aviation Week & Space Technology.