Live Countdown Coverage Begins for SpaceX’s CRS-21 Mission

SpaceX's CRS-21 mission.
A SpaceX Falcon 9 rocket, with the upgraded cargo Dragon spacecraft atop, stands ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida on Dec. 5, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:17 a.m. EST on Sunday, Dec. 6. Photo credit: SpaceX

Hello, and good morning from NASA’s Kennedy Space Center in Florida! Live countdown coverage for the launch of SpaceX’s 21st resupply services (CRS-21) mission to the International Space Station has begun – watch now on NASA TV or the agency’s website.

SpaceX's Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff for CRS-21.
The upgraded SpaceX Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida after being raised to a vertical position on Dec. 2, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:17 a.m. on Sunday, Dec. 6. Photo credit: SpaceX

The uncrewed cargo Dragon spacecraft and Falcon 9 rocket are scheduled to lift off from Kennedy’s Launch Complex 39A in just about 30 minutes, at 11:17 a.m. EST. The mission will deliver more than 6,400 pounds of supplies, equipment, and critical materials to support dozens of science and research experiments that will take place during Expeditions 64 and 65.

About 12 minutes after today’s launch, Dragon will separate from the Falcon 9 rocket’s second stage, beginning a series of carefully choreographed thruster firings to reach the orbiting laboratory. Here’s a full look at today’s countdown and ascent milestones. All times are approximate:

COUNTDOWN
Hour/Min/Sec – Events
-00:38:00 – SpaceX Launch Director verifies go for propellant load
-00:35:00 – RP-1 (rocket-grade kerosene) loading begins
-00:35:00 – 1st stage LOX (liquid oxygen) loading begins
-00:16:00 – 2nd stage LOX loading begins
-00:07:00 – Falcon 9 begins pre-launch engine chill
-00:05:00 – Dragon transitions to internal power
-00:01:00 – Command flight computer to begin final prelaunch checks
-00:01:00 – Propellant tanks pressurize for flight
-00:00:45 – SpaceX Launch Director verifies go for launch
-00:00:03 – Engine controller commands engine ignition sequence to start
-00:00:00 – Falcon 9 liftoff

LAUNCH, LANDING AND DRAGON DEPLOYMENT
Hour/Min/Sec – Event
00:01:18 – Max Q (moment of peak mechanical stress on the rocket)
00:02:30 – 1st stage main engine cutoff (MECO)
00:02:34 – 1st and 2nd stages separate
00:02:41 – 2nd stage engine starts
00:06:37 – 1st stage entry burn begins
00:08:38 – 2nd stage engine cutoff (SECO)
00:08:38 – 1st stage landing
00:11:49 – Dragon separates from 2nd stage
00:12:35 – Dragon nosecone open sequence begins

SpaceX Falcon 9 and Cargo Dragon Stand Ready for CRS-21 Launch

A SpaceX Falcon 9 rocket and cargo Dragon spacecraft stand ready for liftoff for the company's CRS-21 mission on Dec. 6, 2020.
A SpaceX Falcon 9 rocket, with the upgraded cargo Dragon spacecraft atop, stands ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida on Dec. 5, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:17 a.m. EST on Sunday, Dec. 6. Photo credit: SpaceX

A SpaceX Falcon 9 rocket and cargo Dragon spacecraft stand ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida for the company’s 21st Commercial Resupply Services (CRS-21) mission to the International Space Station. Launch is scheduled for today, Dec. 6, at 11:17 a.m. EST.

Meteorologists with the U.S. Air Force 45th Space Wing are predicting a 60% chance of favorable weather conditions for today’s launch, with the primary concern revolving around the thick cloud layer rule.

Some of the science that will be delivered on this mission includes 3D engineered heart tissues for a study that will examine how prolonged exposure to microgravity affects the human heart, meteorite samples and microbes to research the formation and biomining of asteroid material in space, and a study that will observe how brain organoids respond to microgravity. More information on these and additional payloads can be found at: https://www.nasa.gov/mission_pages/station/research/news/spacex-21-research-highlights

Tune in to NASA TV or the agency’s website at 10:45 a.m. EST for live launch countdown coverage or follow along right here on the blog.

NASA, SpaceX Now Targeting Dec. 6 for CRS-21 Launch

CRS-20 liftoff
A SpaceX Falcon 9 rocket lifts off from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida at 11:50 p.m. EST on March 6, 2020, carrying the uncrewed cargo Dragon spacecraft on its journey to the International Space Station for NASA and SpaceX’s 20th Commercial Resupply Services (CRS-20) mission. Photo credit: NASA/Tony Gray and Tim Terry

Because of poor weather conditions in the recovery area for today’s planned launch of SpaceX’s 21st commercial resupply services mission to the International Space Station, SpaceX and NASA are now targeting lift off for Sunday, Dec. 6, at 11:17 a.m. EST. Launch coverage will begin at 10:45 a.m. on NASA TV and the agency’s website.

A launch Sunday would lead to docking Monday, Dec. 7, for the Dragon to deliver about 6,400 pounds of important science and research, cargo supplies, and the first privately funded commercial airlock to the Expedition 64 crew aboard the orbiting laboratory.

Follow launch activities at the launch blog and @NASAKennedy and learn more about space station activities by following @space_station and @ISS_Research on Twitter as well as the ISS Facebook and ISS Instagram accounts.

NASA, SpaceX ‘Go’ for Tomorrow’s CRS-21 Launch

A prelaunch news conference is held for CRS-21 on Dec. 4, 2020.
NASA and SpaceX conduct a prelaunch news conference on Dec. 4, 2020, at NASA’s Kennedy Space Center in Florida ahead of SpaceX’s 21st Commercial Resupply Services (CRS-21) launch. From left are: Kenny Todd, deputy program manager of NASA’s International Space Station Program Office; Kirt Costello, chief scientist of NASA’s International Space Station Program Office; Sarah Walker, director of SpaceX Dragon Mission Management; and Melody Lovin, launch and weather officer for the 45th Space Wing’s U.S. Space Force. Photo credit: NASA/Isaac Watson

Following a prelaunch news conference at NASA’s Kennedy Space Center in Florida, NASA and SpaceX remain “go” for tomorrow’s launch of SpaceX’s 21st Commercial Resupply Services mission to the International Space Station.

CRS-21 logo“This morning, we did a mission management team meeting, and we had a unanimous go for this launch and docking,” said Kenny Todd, deputy program manager of NASA’s International Space Station Program Office. “We’re excited to get on with it; we’ll see how things play out over the next couple of days, but hopefully by the middle of the week, we’ll have a Dragon on the way, if not already attached (to station).”

SpaceX’s Falcon 9 rocket, with the upgraded cargo Dragon spacecraft atop, stands poised for launch at Kennedy’s Launch Complex 39A, and weather officials are now predicting a 50% chance of favorable weather conditions for liftoff. While that’s a slight increase over previous launch forecasts, a cold front moving across the state of Florida will have teams keeping a close eye on the weather.

“Previously, it looked like that cold front would be passing right during the launch window, but the trend is now our friend – the models are now bringing that cold front through prior to the launch window,” said Melody Lovin, U.S. Space Force launch and weather officer for the 45th Space Wing.

“Because of that, we’re expecting most of the rain associated with the cold front to be pretty much done before the launch window opens up. We’re not exactly sure when the clouds are going to clear out of the way for us. We’re hoping the earlier the cold front will pass, the more clearing we’ll get.”

SpaceX's Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff for CRS-21.
The upgraded SpaceX Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida after being raised to a vertical position on Dec. 2, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:39 a.m. on Saturday, Dec. 5. Photo credit: SpaceX

The first mission for SpaceX under NASA’s second Commercial Resupply Services contract, CRS-21 will deliver more than 6,400 pounds of supplies, equipment, and critical materials needed to support a variety of science and research investigations that will occur during Expeditions 64 and 65. With SpaceX’s Crew Dragon carrying a crew of four to the orbiting laboratory last month, the mission will also mark the first time two Dragon spacecraft will be attached to the space station simultaneously.

“It really ushers in a season of continuous Dragon presence for the near future,” said Sarah Walker, director of SpaceX Dragon Mission Management. “We’re excited about all of the missions that we’ll be flying for NASA and the International Space Station program, both cargo and crew, and it’s really just an honor to be a part of that.”

Dragon will spend about one month attached to the orbiting laboratory before autonomously undocking and returning to Earth with 5,200 pounds research and return cargo. The spacecraft is slated to splash down in the Atlantic Ocean upon its arrival.

Liftoff is targeted for 11:39 a.m. EST tomorrow, Dec. 5, with live launch countdown coverage beginning at 11:15 a.m. EST. Follow along here on the blog, NASA TV, or the agency’s website. Learn more about the mission at: https://www.nasa.gov/sites/default/files/atoms/files/spacex_crs-21_mision_overview_high_res_0.pdf

CRS-21 Prelaunch News Conference Set for 4 p.m. Today, Dec. 4

A SpaceX Falcon 9 rocket and Cargo Dragon spacecraft stand ready for liftoff for the company's CRS-21 launch.
A SpaceX Falcon 9 rocket, with the upgraded Cargo Dragon spacecraft atop, stands ready for liftoff NASA Kennedy Space Center’s Launch Complex 39A in Florida after being raised to a vertical position on Dec. 2, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:39 a.m. on Saturday, Dec. 5. Photo credit: SpaceX

The launch readiness review for SpaceX’s 21st Commercial Resupply Services (CRS-21) mission to the International Space Station has concluded, and the prelaunch news conference is set for 4 p.m. EST today, Dec. 4, from NASA’s Kennedy Space Center in Florida. Watch live on NASA TV or the agency’s website.

Participants include:

  • Kenny Todd, deputy program manager, International Space Station Program Office
  • Kirt Costello, chief scientist, International Space Station Program Office
  • Sarah Walker, director, Dragon Mission Management, SpaceX
  • Melody Lovin, launch weather officer, U.S. Air Force 45th Space Wing

Liftoff of the Falcon 9 rocket and cargo Dragon spacecraft is scheduled for 11:39 a.m. EST tomorrow, Dec. 5, from Kennedy’s Launch Complex 39A. Weather officials with the U.S. Air Force 45th Space Wing are predicting a 50% chance of favorable weather conditions for launch. Primary weather concerns are the cumulus cloud rule and the thick layer cloud rule.

Tune in for SpaceX CRS-21 Prelaunch Events

CRS-20 liftoff
A SpaceX Falcon 9 rocket lifts off from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida at 11:50 p.m. EST on March 6, 2020, carrying the uncrewed cargo Dragon spacecraft on its journey to the International Space Station for NASA and SpaceX’s 20th Commercial Resupply Services (CRS-20) mission. Photo credit: NASA/Tony Gray and Tim Terry

Beginning at 1 p.m. EST today, Dec. 4, tune in for the CRS-21 Virtual #NASASocial Science and Station Q&A, airing live on NASA TV and the agency’s website. Following this, later in the afternoon, there will be a prelaunch news conference (this will occur approximately one hour after the conclusion of the launch readiness review.) Participants include:

  • Kenny Todd, deputy program manager, International Space Station Program Office
  • Kirt Costello, chief scientist, International Space Station Program Office
  • Sarah Walker, director, Dragon Mission Management, SpaceX
  • Melody Lovin, launch weather officer, U.S. Air Force 45th Space Wing

CRS-21 logoSpaceX’s 21st Commercial Resupply Services mission to the International Space Station is scheduled for tomorrow, Dec. 5. Liftoff of the SpaceX Falcon 9 rocket and cargo Dragon spacecraft is targeted for 11:39 a.m. EST from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. Live launch coverage begins at 11:15 a.m. EST here on the blog, NASA TV, and the agency’s website.

Weather officials with the U.S. Air Force 45th Space Wing are now predicting a 50% chance of favorable weather conditions for liftoff. Primary weather concerns continue to revolve around the cumulus cloud rule and thick cloud layer rule.

Packed inside Dragon are critical science investigations, supplies, and equipment bound for the orbiting laboratory. One item for delivery is the Nanoracks Bishop Airlock – the first commercially owned and operated airlock that, once installed, will provide a variety of capabilities to the space station, such as payload hosting, robotics testing, and satellite deployment.

Learn more about some of the science and payloads on board at: https://www.nasa.gov/mission_pages/station/research/news/spacex-21-research-highlights.

NASA, SpaceX on Track for Dec. 5 Cargo Resupply Launch

A SpaceX Falcon 9 rocket and Cargo Dragon spacecraft stand ready for liftoff for the company's CRS-21 launch.
A SpaceX Falcon 9 rocket, with the upgraded Cargo Dragon spacecraft atop, stands ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida after being raised to a vertical position on Dec. 2, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:39 a.m. on Saturday, Dec. 5. Photo credit: SpaceX

NASA and SpaceX are targeting Saturday, Dec. 5, for SpaceX’s 21st Commercial Resupply Services (CRS-21) mission to the International Space Station. Weather officials with the U.S. Air Force 45th Space Wing are predicting a 40% chance of favorable weather conditions for liftoff of the SpaceX Falcon 9 rocket and Cargo Dragon spacecraft from Kennedy Space Center’s Launch Complex 39A in Florida.

Primary weather concerns are the cumulus cloud rule, thick cloud layer rule, and flight through precipitation.

SpaceX's Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff for CRS-21.
The upgraded SpaceX Cargo Dragon spacecraft and Falcon 9 rocket stand ready for liftoff at NASA Kennedy Space Center’s Launch Complex 39A in Florida after being raised to a vertical position on Dec. 2, 2020, ahead of the company’s 21st Commercial Resupply Services (CRS-21) launch. Liftoff of the Falcon 9 is scheduled for 11:39 a.m. on Saturday, Dec. 5. Photo credit: SpaceX

CRS-21 is the first mission under the company’s second Commercial Resupply Services contract with NASA and the first flight of the upgraded cargo version of Dragon 2. The mission will deliver supplies, equipment, and critical materials to support dozens of the more than 250 science and research investigations that will occur aboard the orbiting laboratory during Expeditions 64 and 65.

Liftoff of the Falcon 9 is scheduled for 11:39 a.m. EST, and Dragon is slated to autonomously dock at the space station at approximately 11:30 a.m. EST on Sunday, Dec. 6. NASA astronauts and Expedition 64 Flight Engineers Kate Rubins and Victor Glover will monitor docking operations.

Follow live coverage of the CRS-21 mission and prelaunch events here on the blog, NASA TV, and the agency’s website:

  • 1 p.m. EST Friday, Dec. 4 – Virtual #NASASocial Science and Station Q&A
  • TBD Friday, Dec. 4 – Prelaunch news conference from Kennedy with representatives from the International Space Station Program Office, SpaceX, and the U.S. Air Force 45th Space Wing
  • 11:15 a.m. EST Saturday, Dec. 5 – Live launch countdown coverage begins

Learn more about station activities by following @space_station and @ISS_Research on Twitter, as well as the ISS Facebook and ISS Instagram accounts.

SpaceX Falcon 9 and Cargo Dragon Prepare for Rollout

Falcon 9 and Cargo Dragon prepare to roll out to the launch pad for CRS-21.
A SpaceX Falcon 9 rocket and Cargo Dragon spacecraft are seen inside the company’s hangar at NASA’s Kennedy Space Center in Florida on Dec. 2, 2020, prior to being rolled out to the launch pad in preparation for the 21st Commercial Resupply Services (CRS-21) launch. Liftoff is scheduled for 11:39 a.m. EST on Saturday, Dec. 5, from Kennedy’s Launch Complex 39A. Photo credit: SpaceX

A SpaceX Falcon 9 rocket, topped with the upgraded version of the Cargo Dragon spacecraft, is seen inside the company’s hangar at NASA’s Kennedy Space Center in Florida on Dec. 2, 2020, prior to being rolled out to the launch pad in preparation for the CRS-21 launch. The rocket and spacecraft are slated to make the short journey to the pad later this afternoon.

The upgraded version of Cargo Dragon for SpaceX's CRS-21 launch.
The upgraded version of SpaceX’s Cargo Dragon spacecraft, Dragon 2, is seen atop the Falcon 9 rocket as they prepare to be rolled to Kennedy Space Center’s Launch Complex 39A on Dec. 2, 2020, in preparation for the company’s 21st Commercial Resupply Services (CRS-21) launch. Photo credit: SpaceX

The first launch for SpaceX under NASA’s second Commercial Resupply Services contract, CRS-21 is scheduled to lift off from Kennedy’s Launch Complex 39A on Saturday, Dec. 5, at 11:39 a.m. EST. Weather officials with the U.S. Air Force 45th Space Wing predict a 40% chance of favorable weather conditions for liftoff, with primary concerns revolving around flight through precipitation, the cumulus cloud rule, and thick cloud layer rule.

The mission will deliver critical supplies and equipment to the International Space Station. Included in that delivery are materials for a variety of science experiments, including meteorite samples and microbes, 3D engineered heart tissues, and a tool being tested for quick and accurate blood analysis in microgravity.

Learn more about some of this mission’s science and its payloads at: https://www.nasa.gov/mission_pages/station/research/news/spacex-21-research-highlights/

NASA and SpaceX “Go” for Dec. 5 Cargo Resupply Launch

A SpaceX Falcon 9 rocket awaits liftoff for SpaceX's 20th Commercial Resupply Services Mission in March 2020.
A SpaceX Falcon 9 rocket and cargo Dragon spacecraft stand ready for liftoff at Cape Canaveral Air Force Station’s Space Launch Complex 40 in Florida on March 6, 2020, for NASA and SpaceX’s 20th Commercial Resupply Services (CRS-20) mission to the International Space Station. Liftoff occurred at 11:50 p.m. EST. Photo credit: NASA/Tony Gray and Tim Terry

NASA and SpaceX managers conducted a Flight Readiness Review (FRR) Monday, Nov. 23, for SpaceX’s 21st Commercial Resupply Services (CRS-21) mission to the International Space Station.

To enable additional time to evaluate flight data from Crew-1 and close out certification work ahead of this first flight of the cargo version of Dragon 2, teams are now proceeding toward a planned liftoff at 11:39 a.m. EST on Saturday, Dec. 5, from Launch Complex 39A at the agency’s Kennedy Space Center in Florida, with the Dragon spacecraft arriving to autonomously dock at the orbiting laboratory on Sunday, Dec. 6, at approximately 11:30 a.m.

The science to be delivered on this mission includes a study aimed at better understanding the effects of microgravity on cardiac function in human heart tissue, research into how microbes could be used for biomining on asteroids, and a tool being tested for quick and accurate blood analysis in microgravity. The first commercially owned and operated airlock on the space station, the Nanoracks Bishop Airlock, will arrive in the unpressurized trunk of the Dragon spacecraft. Bishop will provide a variety of capabilities to the orbiting laboratory, including CubeSat deployment and support of external payloads.