{"id":12801,"date":"2019-12-03T20:30:47","date_gmt":"2019-12-03T12:30:47","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/long-duration-coast-experiment-on-tap-after-falcon-9-launch-thursday\/"},"modified":"2019-12-03T20:30:47","modified_gmt":"2019-12-03T12:30:47","slug":"long-duration-coast-experiment-on-tap-after-falcon-9-launch-thursday","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/long-duration-coast-experiment-on-tap-after-falcon-9-launch-thursday\/","title":{"rendered":"Long-duration coast experiment on tap after Falcon 9 launch Thursday"},"content":{"rendered":"

EDITOR\u2019S NOTE: <\/strong>Updated Dec. 4 after scrub.<\/p>\n

\"\"
Artist\u2019s illustration of a Falcon 9 rocket\u2019s upper stage. Credit: SpaceX<\/figcaption><\/figure>\n

SpaceX will perform a multi-hour experiment on the second stage of a Falcon 9 rocket after the launcher deploys a Dragon supply ship on the way to the International Space Station Thursday, gathering thermal data and other information to verify the vehicle\u2019s ability to perform long-duration missions and inject payloads into demanding, high-energy orbits.<\/p>\n

The experiment will use up some of the Falcon 9\u2019s excess lift capacity, leaving an insufficient fuel reserve in the rocket\u2019s first stage to perform maneuvers to return to a propulsive landing at SpaceX\u2019s recovery site at Cape Canaveral. Instead, the first stage will aim for a landing on a SpaceX drone ship parked in the Atlantic Ocean.<\/p>\n

SpaceX scrubbed Falcon 9 launch attempt Wednesday due to brisk upper level winds and poor conditions in the offshore first stage landing zone.<\/p>\n

\u201cAfter Dragon is dropped off into orbit, the Falcon 9 second stage stage is going to continue on for a thermal demonstration,\u201d said Jessica Jensen, director of Dragon mission management at SpaceX. \u201cSo it\u2019s going to be a long six-hour coast that then results in a disposal burn.<\/p>\n

\u201cWe need extra performance for that demonstration, so basically what we have to do is burn the first stage for a longer period of time, so that the second stage can have its performance reserved for that demo,\u201d Jensen said Tuesday. \u201cSince we\u2019re burning the first stage for a longer period of time, it doesn\u2019t have as much fuel to come all the way back to the launch site. So we\u2019ll do a partial boost-back, which is where the drone ship is located.\u201d<\/p>\n

On Thursday\u2019s flight \u2014 SpaceX\u2019s 19th cargo launch to the space station \u2014 nine kerosene-fueled Merlin 1D engines on the Falcon 9\u2019s first stage will cut off at T+plus 2 minutes, 31 seconds, before separating to allow the rocket\u2019s single-engine second stage to accelerate the Dragon capsule into orbit.<\/p>\n

That burn time is about 13 seconds longer than the first stage firing on SpaceX\u2019s most recent Dragon cargo launch in July, when the booster had enough leftover propellant to return to a landing at Cape Canaveral.<\/p>\n

Jensen said SpaceX is performing the thermal demonstration on Thursday\u2019s launch for \u201csome of our other customers for longer missions that we\u2019re going to have to fly in the future.\u201d<\/p>\n

She said SpaceX will measure the thermal environment in the second stage propellant tanks, along with other parameters, then reignite the stage\u2019s single Merlin engine for a disposal burn.<\/p>\n

SpaceX\u2019s acknowledgement of the bonus objectives planned on this week\u2019s Falcon 9 launch helps explain an unusual airspace warning notice, or NOTAM, indicating the rocket\u2019s second stage would deorbit and fall back into Earth\u2019s atmosphere over the far southern Indian Ocean. Most of the rocket body is expected to burn up during re-entry.<\/p>\n

The timing and location of the NOTAM hinted that SpaceX planned something unusual for the Falcon 9\u2019s second stage after releasing the Dragon cargo capsule in orbit, according to Marco Langbroek, an experienced tracker of satellite movements who lives in the Netherlands.<\/p>\n

In a blog post, Langbroek wrote that the airspace warning suggests the Falcon 9 rocket will steer into a higher-inclination orbit after deploying the Dragon spacecraft into the space station\u2019s orbital plane inclined 51.6 degrees to the equator. The NOTAM indicates the upper stage will deorbit around five-and-a-half hours after launch.<\/p>\n

SpaceX has performed long-duration missions on two Falcon Heavy launches to date.<\/p>\n

During the company\u2019s first Falcon Heavy test flight in February 2018, the rocket\u2019s second stage reignited its upper stage engine after coasting in orbit more than five hours, a maneuver that sent a repurposed Tesla Roadster on a trajectory to escape the grip of Earth\u2019s gravity.<\/p>\n

A Falcon Heavy mission in June for the U.S. Air Force included four upper stage engine burns over three-and-a-half hours to deploy two dozen satellites into three different orbits around Earth.<\/p>\n

Long-duration missions lasting more than five-to-six hours are required to place satellites on trajectories high above Earth, such as circular geosynchronous orbits, where spacecraft linger over the same geographic region at an altitude of more than 22,000 miles (nearly 36,000 kilometers) over the equator.<\/p>\n

While SpaceX did not identify what customers might need a long-duration launch profile, some of the U.S. government\u2019s top secret spy satellites require direct rides to geosynchronous orbits. The Delta 4-Heavy rocket built and flown by United Launch Alliance often delivers those clandestine payloads to space, but ULA is retiring the Delta 4-Heavy. ULA\u2019s next-generation Vulcan Centaur rocket and SpaceX\u2019s launch vehicles are less expensive than the Delta 4-Heavy, which has launched 11 times since 2004.<\/p>\n

The U.S. Air Force also occasionally flies satellite missions that require multi-hour launch profiles.<\/p>\n

In contrast, SpaceX\u2019s Dragon missions to the International Space Station reach their targeted deployment orbits in less than 10 minutes. A commercial communications satellite is typically released from the Falcon 9 launcher around a half-hour after liftoff.<\/p>\n

Email the author.<\/i><\/b><\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/strong><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

EDITOR\u2019S NOTE: Updated Dec. 4 after scrub. Artist\u2019s illustration of a Falcon 9 rocket\u2019s upper stage. Credit: SpaceX SpaceX will perform a multi-hour experiment on the second stage of a Falcon 9 rocket after the launcher deploys a Dragon supply ship on the way to the International Space Station Thursday, gathering thermal data and other information […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[291,1736,1395,479,25,257,316,2402],"class_list":["post-12801","post","type-post","status-publish","format-standard","hentry","category-news","tag-commercial-space","tag-complex-40","tag-dragon","tag-falcon-9","tag-launch","tag-military-space","tag-spacex","tag-spacex-crs-19"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/12801"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=12801"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/12801\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=12801"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=12801"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=12801"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}