PARIS — The Sept. 29 reignition failure of the Space Exploration Technologies Corp. (SpaceX) Falcon 9 v1.1 rocket was caused when the engine’s igniter fluid lines froze following exposure to supercold oxygen and prevented a full second burn, SpaceX and other industry officials said.

While the Sept. 29 flight completed part of its mission — delivering a Canadian research satellite into low Earth orbit — it did not complete a full qualification of its upper stage’s reignition capability, which will be indispensable for the rocket’s imminent entry into the commercial market for geostationary-orbiting telecommunications satellites.

Nonetheless, because the reignition anomaly appears so basic, and the fix so simple — adding thermal insulation — insurance underwriters and satellite fleet operator SES of Luxembourg have agreed to proceed with the launch of the SES-8 telecommunications satellite without seeing a flight demonstration of the reignition capability.

SES-8, which is insured for $200 million, is in final preparations for a Falcon 9 v1.1 launch the week of Nov. 25 from Cape Canaveral Air Force Station, Fla. SES paid a premium of about $24 million for the policy.

Much is riding on this flight beyond SES’s satellite.

SES is the world’s second-largest commercial satellite fleet operator with 50-plus spacecraft in orbit. Merely replacing this capacity means the company launches three or four satellites per year. Any expansion, and SES is expanding, means more-frequent launches.

SES’s three to four annual launches are part of a total global commercial market of between 20 and 25 launches per year.

A successful SES-8 mission that fully demonstrates Falcon 9’s performance to geostationary transfer orbit, the destination of most telecommunications satellites, would open the commercial market to Hawthorne, Calif.-based SpaceX.

SpaceX already has a backlog of commercial launches valued at more than $1 billion, about half of which is for satellites heading to geostationary orbit. The other half is made up launches of low-orbiting spacecraft.

SpaceX Chief Executive Elon Musk said following the Sept. 29 flight that the Falcon 9 v1.1 upper stage had demonstrated its reignition capability on multiple occasions during ground tests, and that the Sept. 29 failure could simply be one of not accounting for all the conditions of the space environment.

That explanation turns out to be correct. In response to SpaceNews inquiries, SpaceX on Nov. 21 issued a statement confirming what industry officials have been saying for several weeks. “The igniter fluid lines froze after longer exposure to cold oxygen,” SpaceX said. “This never happened on the ground because ambient air kept the lines warm. We’ve added insulation and made sure that cold oxygen can’t impinge on the lines.”

Peter B. de Selding was the Paris bureau chief for SpaceNews.