HOUSTON — Astronauts aboard the International Space Station re-sealed the hatch to the Dragon spacecraft on the eve of the capsule’s May 31 departure and the rapid series of events that will transfer control of the landmark commercial-supply flight back to SpaceX for re-entry and a Pacific Ocean splashdown and recovery. If the final leg of the nine-day test flight unfolds as planned, Dragon and a 1,400-lb. return cargo will splash down 560 mi. southwest of Los Angeles shortly before 12 p.m. EDT.

SAN FRANCISCO — Preparations are under way for the low-energy launch of a high-energy X-ray telescope developed to count black holes in the Milky Way, study how particles are created when massive stars explode and how their particles are accelerated to nearly the speed of light. The Nuclear Spectroscopic Telescope Array (NuStar) is to be drop-launched June 13 by an Orbital Sciences Pegasus XL from the company’s modified L-1011 “Stargazer” aircraft at 8:30 a.m. PDT.

Locked in the Falcon 9 second stage was a container holding the individual cremated remains of 320 'passengers'

AIR LAUNCH: The U.S. Defense Advanced Research Projects Agency has awarded Lockheed Martin a $6.2 million contract, and Northrop Grumman $2.3 million, for Phase 1 of the Airborne Launch Assist Space Access (Alasa) program to launch a 100-lb. satellite into low Earth orbit from an aircraft for less than $1 million per launch, including range costs. Space Information Laboratories has received $1.9 million to develop enabling technology for a GPS tracking, autonomous flight termination and space-based range system to reduce launch costs.

EXTENDED OPS: With virtually all the objectives of its primary Moon-mapping mission accomplished, NASA’s twin-spacecraft Gravity Recovery and Interior Laboratory (Grail) mission will take a break before beginning a period of extended operations set to begin Aug. 30 and last through Dec. 3. Both spacecraft instruments will be powered off until the extended mission begins. Since March 8, the spacecraft have operated around the clock for 89 days, NASA says.

Boeing is on track to meet its milestones in the second phase of NASA’s Commercial Crew Development (CCDev-2) competition, after completing a preliminary design review earlier this month for software needed to operate its CST-100 crew capsule. Still to come are CCDev-2 milestones that include an orbital maneuvering/attitude control engine hot-fire test, NASA says, adding that “all of NASA’s industry partners, including Boeing, continue to meet their established milestones in developing commercial crew transportation capabilities.”

HOUSTON — The NASA-led International Space Station (ISS) Mission Management Team has approved plans for the scheduled unberthing of the first U.S. commercial resupply mission spacecraft later this week, as the astronauts aboard the orbiting science laboratory wrapped up a fast-paced, 2,400-lb. cargo exchange.

HOUSTON — The SpaceX Dragon capsule rendezvoused with the International Space Station (ISS) May 25, overcoming some late tracking issues to become the first U.S. commercial resupply craft to dock with the six-person orbital science laboratory. Astronauts Don Pettit, Andre Kuipers and Joe Acaba grappled the unpiloted spacecraft with the station’s 17.6-meter (58-ft.) Canadarm2 at 9:56 a.m. EDT, as Dragon flew in formation 10 meters below. The freighter was berthed at the station’s U.S. segment Harmony module at 12:02 p.m. EDT.