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.

SpaceX’s CRS-21: A Mission of Many Firsts

CRS-21 mission firsts graphic.

While this launch marks the first under SpaceX’s second Commercial Resupply Services contract with NASA, the mission also brings many other firsts to the table:

  • CRS-21 will be the first to splash down in the Atlantic Ocean upon the uncrewed cargo Dragon’s return to Earth
  • First time the crew access arm was used to load a cargo resupply mission
  • The first time there will be two Dragon spacecraft docked to the International Space Station (uncrewed cargo Dragon and the Crew-1 Dragon)
  • First automated docking to station for a SpaceX cargo resupply mission
  • First flight of SpaceX’s upgraded cargo version of Dragon, which can carry more science payloads to and from the space station

With the upgraded Dragon spacecraft comes double the capacity for powered lockers that preserve science and research samples during transport to or from Earth. The CRS-1 Dragon had six lockers available, whereas the upgraded version of Dragon has 12.

The upgraded Dragon also provides the capability for science payloads to remain in the spacecraft for the full duration of the mission. While the spacecraft is docked at the orbiting laboratory during CRS-21, four powered payloads will reside in Dragon.

Astronauts Relax Friday Before Weekend Filled with Cargo and Science

Expedition 64 Flight Engineers (clockwise from top left) Victor Glover, Michael Hopkins and Soichi Noguchi pose together for a playful portrait inside the U.S. Destiny laboratory module.
Expedition 64 Flight Engineers (clockwise from top left) Victor Glover, Michael Hopkins and Soichi Noguchi pose together for a playful portrait inside the U.S. Destiny laboratory module.

Five Expedition 64 astronauts are relaxing aboard the International Space Station today as they get ready for the arrival of the next-generation SpaceX Dragon resupply ship. The two cosmonauts stayed focused on their contingent of Russian space science and lab maintenance.

The Falcon 9 rocket that will carry the Cargo Dragon spacecraft into Earth orbit stands at its launch pad at Kennedy Space Center in Florida. Currently, there is a 50% chance of favorable weather conditions for a launch on Saturday at 11:39 a.m. EST to the orbiting lab.

Flight Engineers Kate Rubins and Victor Glover will be on duty early Sunday to monitor the Cargo Dragon’s approach and rendezvous. Its automated docking is planned for 11 a.m. to the Harmony module’s space-facing port adjacent to the Crew Dragon vehicle. The duo will also be readying the Tranquility module for Dragon’s primary payload, the NanoRacks Bishop science airlock.

The other three astronauts, Shannon Walker, Soichi Noguchi and Michael Hopkins, will be working on Sunday servicing a variety of research gear. They will be checking out advanced hardware like the Kubik incubator, the Hermes planetary science facility, the Electrostatic Levitation Furnace and a specialized science freezer nicknamed FRIDGE.

The station’s two cosmonauts, Commander Sergey Ryzhikov and Flight Engineer Sergey Kud-Sverchkov, spent Friday day on research and maintenance tasks.  The Russian duo explored ways to improve the effectiveness of space exercise and also worked on lab computers and life support gear.

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.

Crew Immersed in Space Science as Cargo Dragon Nears Launch

The upgraded version of SpaceX’s Cargo Dragon spacecraft is seen before it rolls out to the launch pad at Kennedy Space Center in Florida.
The upgraded version of SpaceX’s Cargo Dragon spacecraft is seen before it rolls out to the launch pad at Kennedy Space Center in Florida.

Expedition 64 is getting ready for over 6,400 pounds of cargo due to arrive this weekend aboard the next-generation SpaceX Dragon space freighter. All seven International Space Station residents also were immersed in microgravity research throughout Thursday.

The SpaceX Falcon 9 rocket carrying the Dragon cargo spacecraft has rolled out to the launch pad at Kennedy Space Center in Florida and is counting down to a Saturday lift off at 11:39 a.m. EST. Weather permitting, Dragon would automatically dock just under 24 hours later to the Harmony module’s space-facing port adjacent to the SpaceX Crew Dragon vehicle.

The Cargo Dragon’s main payload is the NanoRacks Bishop airlock that will be robotically attached to the Tranquility module. Bishop will increase the capacity for external space research at the space station benefitting public and private organizations.

The orbiting lab was humming today with a host of advanced space science looking at a variety of microgravity phenomena to enhance life for humans on and off the Earth.

Flight Engineers Michael Hopkins and Sergey Kud-Sverchkov swapped fuel bottles inside the Combustion Integrated Rack that enables safe investigations of flames and fuels on the station. Eye exams were on the slate this afternoon for astronauts Kate Rubins and Soichi Noguchi who also serviced botany and cell biology research gear.

NASA Flight Engineer Shannon Walker serviced samples inside the Materials Science Laboratory before setting up the Fiber Optic Production study inside the Microgravity Science Glovebox. Her crewmate, Flight Engineer Victor Glover collected and stowed biological samples for the Food Physiology study exploring how diet affects the immune system in space.

Finally, station Commander Sergey Ryzhikov of Roscosmos wrapped up a 24-hour session that monitored his heart activity. The two-time station resident also explored ways to improve the workspace inside the station.

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.