HUNTSVILLE, Ala. — Houston-based space services firm NanoRacks unknowingly dodged a bullet when it shifted a $10 million piece of equipment off the Antares rocket that exploded seconds after liftoff Oct. 28 from Wallops Island, Virginia. But other Antares’ passengers were not so lucky, including a NanoRacks client that lost more than two dozen Earth-imaging cubesats in the mishap.

Needing more time for testing, NanoRacks decided in October to wait for Orbital Sciences Corp.’s fourth paid cargo run to send its External Research Platform up to the international space station. That mission, dubbed Orb-4, had been slated for April 1, 2015, but is now in doubt pending the investigation of the Orb-3 near-pad failure, which destroyed the Antares and a Cygnus resupply vehicle laden with space station cargo.

NanoRacks’ External Research Platform is roughly twice the size of a microwave oven and took about two years and $10 million to build under a contract with Astrium North America. NanoRacks markets the platform, equipped with a power supply for payloads that require it, as a means to test previously unflown space hardware, or conduct science experiments requiring exposure to space.

“Our External Payload Platform has been scheduled to fly on Orb-4,” NanoRacks spokeswoman Abby Dickes wrote in an Oct. 29 email. “NanoRacks needed additional time for flight verification testing, so we decided to play it safe and push the flight back.”

Dickes would not comment about whether NanoRacks would wait for Antares’ return to flight or try to get the External Research Platform delivered to space station aboard a Space Exploration Technologies Corp. Dragon capsule, the other cargo service under contract to NASA to deliver 20 metric tons of payload to the ISS by 2017.

NanoRacks already has plans to ship a replacement control module for its malfunctioning small-satellite dispenser to station on SpaceX’s fifth paid cargo run. That mission, one of 12 SpaceX owes NASA under its own $1.8 billion Commercial Resupply Services contract, was slated to lift off in December but could be moved up now that Orbital has missed a delivery.

NanoRacks operates two satellite dispensers aboard station, each of which houses as many as eight cubesats — satellites measuring 10 centimeters on a side and weighing roughly a few kilograms each. In August, one dispenser malfunctioned, alternatively refusing to launch cubesats and then kicking out a pair of the small spacecraft apparently without prompting. In October, at the 65th International Astronautical Congress in Toronto, NanoRacks Managing Director Jeffrey Manber said the root cause of the malfunction had been traced to dispenser screws that had been torqued down too tightly.

NASA spokesman Dan Huot, in an Oct. 28 email, said the new control module NanoRacks plans to send to station aboard Dragon should fix the problem, although NASA has not yet scheduled an installation date. Huot added that the same Dragon spacecraft that brings up the control module will bring one of the two NanoRacks dispensers, which is currently clogged with six cubesats, back to Earth for repairs. The dispenser chute that will remain aboard station still has eight cubesats in it, Huot wrote.

Among the NanoRacks customers waiting for the deployer to be repaired is Planet Labs of San Francisco, which lost a cluster of 26 Earth-observing Dove satellites in the Oct. 28 Antares failure. Planet Labs was a repeat customer for Orbital, which in July launched 28 Doves to station. There were still 18 Doves left to launch when NanoRacks’ dispenser malfunctioned in August.

In a note posted to its website Oct. 28, Planet Labs said the Antares failure “is not catastrophic to our company” because it has “already launched 71 Doves in 18 months on six launch vehicles.”

NanoRacks, which got its start brokering research space for non-NASA customers aboard the space shuttle and space station, has come to rely on cubesat deployments from station for most of its revenue. The company charges roughly $85,000 to launch a single cubesat from the dispensers located in the space station’s Japanese Experimental Module, Manber told SpaceNews in July.

Planet Labs was not the only NanoRacks client to lose hardware in the Antares failure. Planetary Resources, the Redmond, Washington, startup with the long-term goal of asteroid mining, lost its first spacecraft, a three-unit cubesat called Arkyd A3 that was to serve as a technology demonstrator for future asteroid observation spacecraft.

Planetary Resources has already started work on a larger technology demonstrator spacecraft, the Arkyd A6. That spacecraft is slated to launch in the third quarter of 2015 as a secondary payload on a U.S. commercial launch vehicle, which company president Chris Lewicki declined to identify for contractual reasons.

In an Oct. 29 interview, Lewicki downplayed the impact the lost satellite had on the company. “We got a lot of value out of it just by getting it to the pad,” he said. “We’re not crying over lost robots.”

Besides the flock of Doves and Arkyd A3, the Antares failure also destroyed the Radiometer Atmospheric CubeSat Experiment, a 5.5-kilogram spacecraft designed by the University of Texas at Austin and NASA’s Jet Propulsion Laboratory in Pasadena, California, to test an experimental radiometer.

SpaceNews senior staff writer Jeff Foust contributed to this to this story from Washington.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.