{"id":10793,"date":"2021-12-07T00:11:03","date_gmt":"2021-12-06T16:11:03","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/ula-to-set-rocket-endurance-record-on-next-launch\/"},"modified":"2021-12-07T00:11:03","modified_gmt":"2021-12-06T16:11:03","slug":"ula-to-set-rocket-endurance-record-on-next-launch","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/ula-to-set-rocket-endurance-record-on-next-launch\/","title":{"rendered":"ULA to set rocket endurance record on next launch"},"content":{"rendered":"
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An Atlas 5 rocket stands on launch pad 41 ahead of the STP-3 mission. Credit: United Launch Alliance<\/figcaption><\/figure>\n

United Launch Alliance\u2019s Atlas 5 rocket will set an endurance record after liftoff from Cape Canaveral Tuesday, targeting the delivery of two U.S. military tech demo satellites directly into a geosynchronous orbit more than 22,000 miles over the equator.<\/p>\n

The Atlas 5\u2019s Centaur upper stage, propelled by an Aerojet Rocketdyne RL10 engine, will maneuver the two Space Force satellites into a geosynchronous orbit with a sequence of three rocket burns over the course of six-and-a-half hours.<\/p>\n

The two satellites host an array of technological prototypes and experiments. Military engineers will test their readiness for use on future operational space missions.<\/p>\n

The launch is sponsored by the military\u2019s Space Test Program, which oversees many of the Defense Department\u2019s experimental space missions. The larger of the two satellites on the Atlas 5 rocket, named STPSat 6 and built by Northrop Grumman, hosts a NASA laser communications experiment and a payload for the National Nuclear Security Administration designed to detect nuclear detonations to verify international treaty compliance.<\/p>\n

The military hasn\u2019t disclosed specifics for other experiments on the mission, but officials said they generally will test technologies related to space domain awareness, space weather monitoring, and communications.<\/p>\n

A rideshare satellite named the Long Duration Propulsive ESPA, or LDPE 1, also is riding to orbit on the Atlas 5 rocket. It is mounted to the rocket below STPSat 6 inside the 17.7-foot (5.4-meter) diameter payload fairing.<\/p>\n

LDPE 1 hosts its own technological experiments, and will have its own propulsion system to maneuver in space. The spacecraft is capable of releasing small satellites into orbit. When asked, military officials would not confirm whether the LDPE 1 spacecraft\u2019s experiments include any deployable smallsats.<\/p>\n

The mission is set to begin with a blastoff from launch pad 41 at Cape Canaveral Space Force Station at 4:04 a.m. EST (0904 GMT) Tuesday, the opening of a two-hour launch window.<\/p>\n

The destination? A nearly circular geosynchronous orbit hugging the equator.<\/p>\n

Most satellites heading to such an orbit get dropped off in an egg-shaped transfer orbit. That requires the spacecraft to use its own propulsion resources to circularize at an operational altitude over the equator.<\/p>\n

Some launches deploy their satellites directly into geosynchronous orbit. ULA\u2019s Atlas 5 and Delta 4 rockets have accomplished this feat before, but the launch Tuesday will set a new record with the Centaur upper stage.<\/p>\n

\u201cThis is a highly complex orbital insertion that requires three Centaur burns and precise navigation, a capability unique to the Atlas 5. This is our longest mission to date at seven hours and 10 minutes until final spacecraft separation,\u201d said Gary Wentz, ULA\u2019s vice president of government and commercial programs.<\/p>\n

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The launch timeline for the STP-3 mission. Credit: United Launch Alliance<\/figcaption><\/figure>\n

ULA\u2019s 196-foot-tall (59.7-meter) Atlas 5 rocket will fly in its most powerful configuration with five strap-on solid rocket boosters clustered around the bottom of the first stage.<\/p>\n

The solid-fueled boosters will provide the majority of the 2.6 million pounds of thrust to drive the Atlas 5 launcher off the pad on a trajectory east from Cape Canaveral. A kerosene-burning RD-180 engine will power the first stage core.<\/p>\n

The mission will mark the 90th flight of an Atlas 5 rocket since 2002, and the 12th in the \u201c551\u201d configuration with five solid rocket boosters and a 5.4-meter (17.7-foot-diameter) payload fairing.<\/p>\n

The five boosters will consume their pre-packed solid fuel in less than two minutes, then release to fall into the Atlantic Ocean. The Atlas 5\u2019s payload shroud will jettison three-and-a-half minutes after liftoff, then the RD-180 main engine will shut down four-and-a-half minutes into the flight.<\/p>\n

The Centaur upper stage\u2019s RL10 engine will ignite for a six-minute burn to reach a parking orbit, then reignite for another six-minute burn at T+plus 1 hour, 7 minutes, to begin the process of boosting the STP-3 payloads to a higher altitude.<\/p>\n

A third and final Centaur maneuver is planned to begin at about T+plus 6 hours, 25 minutes, to steer the STP-3 payloads into their targeted circular orbit over the equator at an altitude of about 22,400 miles (36,100 kilometers).<\/p>\n

That distance is just above geostationary altitude, where satellites circle Earth at the same rate of the planet\u2019s rotation. STPSat 6 will settle into a parking spot within visibility of the Americas and the Pacific Ocean, while LDPE 1\u2019s destination and final orbital position have not been disclosed by the Space Force.<\/p>\n