Update for Dec. 21: SpaceX has successfully launched its Dragon CRS-24 mission for NASA and landed a rocket for the 100th time. Read our full wrap story here.
CAPE CANAVERAL, Fla. — SpaceX will launch a Dragon spacecraft packed with NASA cargo to the International Space Station early Tuesday (Dec. 21) as part of its latest resupply mission for the U.S. space agency and you can watch it live.
A shiny new SpaceX Falcon 9 rocket will take to the skies here from NASA’s Kennedy Space Center at 5:06 a.m. EST (1006 GMT). The two-stage launcher will blast off from Pad 39 lofting a robotic Dragon cargo capsule carrying more than 6,500 pounds (2,948 kilograms) of fresh supplies, experiment hardware, and other gear for the astronauts aboard the orbiting lab.
Tuesday's launch attempt will be the third launch for SpaceX in 72 hours after two Saturday liftoffs for both Turkey's Turksat 5B satellite and the company's own Starlink internet satellites. But that's only if the Dragon can get off the ground.
The weather outlook is iffy going into Tuesday's attempt, with forecasters at the 45th Weather Squadron predicting a 30% chance of favorable conditions for liftoff. The primary concerns being cumulus clouds, thick clouds, and surface electricity rule.
There is another opportunity on Wednesday if the rocket can't get off the ground; with, the weather report improves significantly to 70% favorable. While the launch weather improves, the booster recovery weather deteriorates slightly as higher seas are expected on Wednesday.
If Dragon can get off the ground as expected, the spacecraft will dock with the space on Wednesday morning (Dec. 22).
"We're keeping our fingers crossed that the launch can get off the ground on Tuesday," Arlena Moses, launch weather officer at with 45th Space Delta at the Cape Canaveral Space Force Station said during a prelaunch news briefing on Monday (Dec. 20). "If we can't, the weather does improve going into Wednesday."
Fresh supplies for space station
Tuesday's cargo launch, dubbed the CRS-24 mission, is SpaceX's fourth resupply flight under the company's second commercial resupply services contract with NASA. It's also the eighth cargo craft to fly this year. SpaceX's Cargo Dragon spacecraft is nearly identical to its astronaut-toting counterpart, called Crew Dragon, and allows SpaceX and NASA to send more cargo to the station than before due to upgrades over Cargo Dragon's predecessor.
Tucked inside this particular cargo craft are research experiments and crew supplies that will support a host of science investigations that focus on life sciences, medicine and much more.
Bob Dempsey, NASA's acting deputy chief scientist for the space station program, told Space.com that the Cargo Dragon spacecraft is an integral part of the agency's commercial resupply program. Not only does it provide NASA with the ability to launch more cargo, it also has a unique capability that no other cargo-toting craft does currently: the ability to bring cargo back home.
Returning cargo is crucial to a lot of different disciplines on station, in particular biomedical research, like the CASIS PCG20 investigation which is a protein crystallization experiment from Merck flying on CRS-24. As part of this investigation, the team will be studying how protein crystals grow in space to improve cancer treatments here on Earth.
Paul Reichert, principal investigator for Merck, said that having the ability to receive the experiment back within hours (compared to days on Merck’s first experiment, which flew on CRS-10 in 2017, will make a big difference in the data.
That’s because once the protein crystals return to Earth, they are affected by gravity. So receiving them back quickly will preserve the data collected.
Also onboard are experiments from two different universities, each looking at bacteria in space. The first, from the University of Idaho, will research how bacteria grow on different types of surfaces in order to develop polymers that could help reduce bacteria spread on future missions.
"When astronauts touch surfaces in space, like on Earth, they can spread bacteria," Dempsey said. "So this will look at bacterial-resistant materials."
Another study from Columbia University in New York will look at the interactions between two different kinds of bacteria. Past studies on Earth have found that these two specific bacteria types can enhance each other's properties, making them more dangerous. The data collected will be published online for anyone to look at and could lead to better antibiotic treatments for future astronauts.
Proctor and Gamble will send Tide detergent to the space to investigate how well it holds up to the rigors of the microgravity environment. Researchers are hoping that this will give future astronauts the ability to do laundry as they venture further out into space.
"We will also have food and gifts for the crew," Joel Montalbano, NASA's space station program manager, said during a prelaunch news briefing on Dec. 20.
While Montalbano wouldn't say what "Santa" was bringing to the station's crew for Christmas, he did say that there would be holiday treats like turkey and a host of other fresh foods.
A rare new Falcon 9
Tuesday's launch marks the 31st flight of the year for SpaceX’s workhorse two-stage Falcon 9 rocket. The liftoff is expected to feature a new Falcon 9 first stage, designated B1069, marking only the second SpaceX launch so far this year to blast off on a new rocket.
It will be the company's sixth Dragon launch of the year, which includes two crew missions as well as three previous cargo flights. The Dragon used in Tuesday's flight will be a previously used cargo craft, having flown on the CRS-22 mission in June. The mission will also continue SpaceX's presence in space, as the company has had two Dragon cargo craft parked to the space station most of the year.
Following an on-time liftoff, the Falcon 9's first stage will return to Earth and touch down on the deck of the drone ship "Just Read the Instructions" approximately nine minutes later. The massive ship is one of three floating platforms that SpaceX now has to catch its rockets.
To date, SpaceX has successfully landed its first-stage boosters 99 times. If successful, Saturday's landing will mark a new milestone for the company — its 100th overall recovery.
Dragon will spend just over 24-hours in orbit as it chases down the space station. After its arrival, the craft will dock itself to the orbital outpost on Wednesday morning (Dec. 22) at 4:30 a.m. EST (0930 GMT).