SpaceX ignited a Falcon 9 rocket for a 10-second test-firing early Thursday on a launch pad at Cape Canaveral, clearing a pre-flight check before a mission set to blast off just after midnight Sunday with the SXM 8 radio broadcasting satellite for SiriusXM.
The static fire test occurred at 2:30 a.m. EDT (0630 GMT) Thursday on pad 40 at Cape Canaveral Space Force Station. The rocket ignited its nine Merlin 1D first stage engines while remaining firmly on the ground at pad 40.
SpaceX conducted test-firing without the SXM 8 satellite on-board. Ground crews planned to lower the Falcon 9 rocket and roll it back into a hangar for attachment of the commercial radio broadcasting spacecraft inside the launcher’s payload fairing.
If all goes according to plan, SpaceX ground crews will return the rocket to pad 40 and lift the 229-foot-tall (70-meter) launch vehicle vertical Saturday.
The mission has a launch window opening at 12:26 a.m. EDT (0426 GMT) and closing at 2:25 a.m. EDT (0625 GMT) Sunday, according to SpaceX.
There is a 60% chance of favorable weather during the nearly two-hour launch window, according to the official launch forecast issued by the U.S. Space Force’s 45th Weather Squadron. The primary weather concern is with debris clouds left over from afternoon and evening thunderstorms in Central Florida.
If the launch is delayed to a backup opportunity at the same time Monday, the forecast improves to an 80% chance of acceptable conditions for liftoff of the Falcon 9 rocket.
Sunday’s launch will mark SpaceX’s 18th Falcon 9 flight of the year, and the second in less than three days. A Falcon 9 rocket lifted off Thursday afternoon from pad 39A at NASA’s Kennedy Space Center — a few miles north of pad 40 — with a Dragon cargo capsule heading for the International Space Station.
SXM 8, built by Maxar, is an identical copy of SiriusXM’s SXM 7 satellite that launched in December on a previous Falcon 9 mission. But a failure in SXM 7’s communications payload prompted the radio broadcaster to declare the satellite a total loss.
SiriusXM confirmed the failure of “certain SXM 7 payload units” in January, following a successful launch and orbit-raising to reach a circular geosynchronous orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator.
In a quarterly earnings report in April, SiriusXM said it recorded a $220 million impairment charge from the failure of the SXM 7 mission. SiriusXM said it has a $225 million insurance covering the launch and first year of in-orbit operations of the SXM 7 satellite, and the company said it expects to file a claim under the policy.
Sean Sullivan, executive vice president and chief financial officer at SiriusXM, said the company has issued a request for proposals to satellite manufacturers to build a replacement for SXM 7.
Maxar said in May that the SXM 7 failure registered a $28 million impact on its financial statement, including $25 million from lost payments from SiriusXM that were due if the spacecraft successfully commenced operations. Maxar spent another $3 million attempting to repair and recover the satellite.
SiriusXM said it does not expect its satellite radio service to be affected by the SXM 7 failure.
SXM 7 was expected to replace the XM 3 radio broadcasting satellite at 85 degrees west longitude, officials said last year. The Boeing-built XM 3 satellite launched in 2005 aboard a Sea Launch Zenit 3SL rocket.
SiriusXM said its XM 3 and XM 4 satellites remain operational in geosynchronous orbit and can continue providing radio broadcast services for several years. Another satellite, XM 5, is available as an in-orbit spare.
Based on Maxar’s 1300-series spacecraft design, the SXM 7 and SXM 8 satellites have large deployable S-band antennas made by L3Harris to broadcast radio signals to SiriusXM’s customers. The S-band reflector is required for the satellite to beam high-power signals to users with small terminals on the ground, such as satellite radio receivers on cars.
“Maxar and SiriusXM have a decades-long relationship, and we’re thrilled to deliver the ninth satellite we’ve built for them since 2000,” said Paul Estey, Maxar’s executive vice president for space programs delivery. “SXM-8, built on Maxar’s proven 1300-class bus, is more than twice as big and powerful as the first-generation SiriusXM constellation built by Maxar.”
The SXM 8 spacecraft weighs about 7.5 tons (nearly 7 metric tons) and stands about 27 feet (8 meters) tall inside the Falcon 9 rocket’s payload shroud.
The spacecraft will ride to space aboard a Falcon 9 rocket powered by a reused first stage booster. The Falcon 9’s second stage will deliver the SXM 8 spacecraft to an elongated geosynchronous transfer orbit, while the booster stage will target a landing back on Earth on a drone ship in the Atlantic Ocean.
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