SiriusXM to replenish radio broadcast fleet with launch early Sunday

The SXM 8 satellite. Credit: Maxar

SiriusXM will get a new radio broadcasting satellite with a launch scheduled early Sunday from Cape Canaveral aboard a SpaceX Falcon 9 rocket, following the failure of an identical spacecraft after a launch last December.

The high-power SXM 8 broadcast satellite, built by Maxar in Palo Alto, California, is tucked inside the nose cone of the Falcon 9 rocket on pad 40 at Cape Canaveral Space Force Station. Liftoff is set for a one-hour, 59-minute launch window opening at 12:26 a.m. EDT (0426 GMT) Sunday.

SXM 8 is the second spacecraft in a two-satellite order placed by SiriusXM in 2016. The first satellite, SXM 7, successfully launched last December on a Falcon 9 rocket but suffered a payload failure before entering service.

SiriusXM confirmed the failure of “certain SXM 7 payload units” in January, following orbit-raising maneuvers 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 after declaring the satellite a total loss. 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.

SiriusXM’s SXM 8 satellite is tucked inside the payload shroud of a SpaceX Falcon 9 rocket awaiting liftoff Sunday. Credit: SpaceX

SXM 8 was originally supposed to replace XM 4, but SiriusXM has not confirmed whether it changed the satellite’s deployment plan after the failure of SXM 7. Officials have also not said what, if any, modifications Maxar made to SXM 8 to eliminate the risk of a similar failure as the one that struck SXM 7.

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.

SpaceX completed a test-firing of the Falcon 9 rocket for the SXM 8 mission early Thursday, then rolled the launcher back into a hangar, where ground teams mounted the SXM 8 spacecraft and its payload fairing to the Falcon 9 upper stage.

SpaceX rolled the Falcon 9 back to pad 40 and raised the 229-foot-tall (70-meter) rocket vertical early Saturday. The weather outlook now shows a 70% chance of favorable weather for launch just after midnight Sunday.

The primary weather concerns are associated with the possibility that debris clouds and anvil clouds from inland thunderstorms could blow back over Florida’s Space Coast and violate launch criteria.

“Ongoing showers and storms are expected to be well inland of the spaceport before sunset, with mid and upper level winds bringing back convective debris clouds and anvil remnants back to the coast for the primary launch late night window,” forecasters wrote. “A few Atlantic showers and cumulus in the vicinity cannot be ruled out, but this no longer looks like the main concern.”

During the launch window, the weather team from the U.S. Space Force predicts scattered clouds at 2,500 feet, an overcast deck of clouds at 18,000 feet, winds from the south-southeast at 12 to 17 mph, and a temperature of about 77 degrees Fahrenheit.

If the launch is delayed to the backup window early Monday, forecasters predict an 80% chance of good weather for liftoff.

The SXM 8 satellite. Credit: Maxar

The mission will be the 18th Falcon 9 flight by SpaceX so far this year, and the eighth Falcon 9 launch in the last 44 days. The busy stretch of SpaceX missions has been dominated by launches deploying the company’s own Starlink internet satellites.

SpaceX is on pace to break the record for the most orbital launches by any U.S. rocket company, but the SXM 8 mission is just SpaceX’s third flight since Jan. 1 primarily dedicated to external commercial customers.

After liftoff from pad 40, the Falcon 9 will head east over the Atlantic Ocean to place the SXM 8 spacecraft into an elongated geosynchronous transfer orbit with an apogee, or high point, about 12,000 miles (20,000 kilometers) above Earth.

The rocket’s first stage, a veteran of two prior missions carrying Crew Dragon spaceships with astronauts, will shut down about two-and-a-half minutes after liftoff and return to a landing on SpaceX’s drone ship “Just Read the Instructions” in the Atlantic.

The Falcon 9’s upper stage will fire its engine two times to inject the SXM 8 spacecraft into its targeted orbit. Spacecraft separation is scheduled for T+plus 31 minutes, 42 seconds.

SXM 8 will unfurl its solar panels and fire its on-board thrusters to maneuver into a circular geosynchronous orbit over the equator, where the satellite will undergo testing before commencing commercial service for SiriusXM.

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