SpaceX launches Dragon cargo capsule to space station, nails rocket landing at sea

CAPE CANAVERAL, Fla. — SpaceX launched its 21st rocket of the year today (Aug 29), sending a robotic Dragon cargo capsule toward the International Space Station (ISS) before nailing a landing at sea. 

A two-stage Falcon 9 rocket blasted off from Launch Complex 39A here at NASA's Kennedy Space Center at 3:14 a.m. EDT (0714 GMT), kicking off the company's 23rd cargo resupply mission to the orbiting lab for NASA. The Dragon is packed with more than 4,800 pounds (2,200 kilograms) of supplies, scientific experiments and hardware, including a new robotic arm that will be tested inside the space station's Bishop Airlock.

A little less than eight minutes after liftoff, the Falcon 9's first stage returned to Earth, landing on one of SpaceX's drone ships in the Atlantic Ocean in a smooth touchdown. The massive ship, called "A Shortfall of Gravitas," is the newest of three drone ships in the company's fleet of recovery vessels that catch falling boosters and return them to port for later reuse. 

"That is the 90th successful landing of an orbital class rocket and the very first for our newest drone ship, 'A Shortfall of Gravitas,'" Andy Tran of SpaceX said during a webcast of this morning's launch. "What a great way to start today's mission."

Related: How SpaceX's Dragon space capsule works (infographic) 

A SpaceX Falcon 9 rocket launches the CRS-23 cargo mission to the International Space Station for NASA on Aug. 29, 2021. (Image credit: NASA TV)

Launch details

Dragon is scheduled to arrive at the station and dock at the Harmony module's space-facing port on Monday (Aug. 30) around 11 a.m. EDT (1500 GMT). There's already another SpaceX vehicle at the orbiting lab: the Crew Dragon "Endeavour," which launched on April 23, carrying a crew of four astronauts. (It's not the first time that two Dragons have been parked at the same time; in fact, there's been at least one Dragon docked to the space station every day so far in 2021.)

Weather officials at the Space Force's 45th Weather Squadron predicted iffy weather for the mission’s first launch attempt, scheduled for Aug. 28. Unfortunately, poor weather at the launch site prompted a 24-hour delay. 

Luckily, the forecast improved dramatically overnight, and Falcon 9 was able to get off the ground as expected.

The first-stage booster featured in today's flight, known as B1061, was a three-time flier. The launcher now has four missions under its belt, after lofting its third Dragon spacecraft. 

The landing today marked the 90th recovery of a Falcon first stage since SpaceX recovered its first booster in 2015.

Related: Watch a SpaceX rocket ace landing on a drone ship in stunning new video

Cargo haul

The newly launched cargo Dragon is carrying a treasure trove of science investigations to the orbital outpost, including a new robotic arm that will be tested out inside the station's newest airlock. As part of a technology demonstration, the robotic arm will flip switches and push buttons in an attempt to prove it has what it takes to carry out routine astronaut tasks.

Also on board are a variety of medical payloads that will help benefit astronauts as well as people on Earth. One such payload, called the Nanofluidic Implant Communication Experiment (NICE), will test out a new drug-delivery device. The tiny implant could change the way people receive their medication and manage chronic illnesses. 

Traditional means of drug delivery include bulky pumps, but that could soon change. The device would be implanted in a patient's arm and would deliver drugs at set intervals, thus allowing the patient to go about their lives, the researchers have said. This type of device would be incredibly helpful for patients like those with rheumatoid arthritis, and those who need to take medicine at all times of the day. 

Another experiment, called MISSE-15, will look at different materials and how they respond to the space environment. Samples of things like concrete, solar panels and more will be exposed to the harsh environment of outer space to test out potential materials for new spacecraft and much more. 

But that's not all. According to Joel Montalbano, ISS program manager for NASA, the crew will also be receiving some special treats in the form of fresh foods and even ice cream. 

"We're sending up a good amount of fruit," Montalbano said during a prelaunch news conference on Friday (Aug. 27). "We have lemons, onions, some avocados, some cherry tomatoes, and also some ice cream. That's a big hit with our crew."

In total, there are more than 4,800 pounds (2,200 kg) of cargo that will help the astronauts perform a variety of research experiments as well as help to restock the station. 

It's been a busy summer on station, with the arrival and installation of new solar arrays, a new Russian science module, and a Northrop Grumman Cygnus cargo ship. 

"Working with SpaceX and working with our other commercial providers has been just an outstanding partnership that we've established between NASA and the commercial industry," Montalbano said. "We are excited to launch this mission and get this incredible science to the station."

A new generation of Dragons

The gumdrop-shaped capsule is the third upgraded Dragon cargo craft to launch to the station after SpaceX retired its previous iteration of cargo Dragon in 2020. It's also the third to launch on this particular Falcon 9.

Designed to hold about 20% more cargo, the current model is nearly identical to its crew-toting counterpart and is bigger on the inside than its predecessor. 

The craft can even store powered payloads while on orbit and can stay on station twice as long as the previous cargo Dragons. Another key upgrade is that the cargo ships will now splash down in the Atlantic Ocean (versus the Pacific splashdowns of past flights), providing a faster return on science. 

That means researchers can get their samples and data back faster — in as little as four to nine hours after splashdown. And SpaceX can get the vehicle back more quickly and start performing inspections and maintenance before the Dragon's next flight. 

Because the newer version of Dragon is better equipped to handle the stresses of a water landing, the teams at SpaceX are able to inspect and refurbish it faster, with less downtime between flights. The Dragon flying today first launched on CRS-21 last year and now has two flights under its belt. 

When it docks with the orbital outpost on Monday morning, there will be two previously flown Dragons parked at the same time. 

SpaceX's Sarah Walker, who leads the company's Dragon program, says that this is the fourth Dragon to launch this year, with at least one more expected to launch before the end of 2021. 

In fact, this will be the third year in a row that at least four Dragon spacecraft have launched, Walker said. She also said that at least one Dragon spacecraft has been parked at the ISS every day so far this year. 

Falcon ferry 

This flight is the 21st for SpaceX's workhorse Falcon 9 so far this year and marks 105 consecutive successful missions since the company's launch failure in 2015. (A second anomaly occurred on the pad in 2016.) 

It also marks the 90th successful recovery of a first-stage booster for the company. 

Today's flight featured a veteran Falcon 9 rocket. The booster, known as B1061, now has four successful flights under its belt, three of which ferried different Dragon spacecraft to the space station. It marks the first SpaceX flight in nearly two months from the Cape. The company's last flight, which blasted off on June 30, delivered more than 80 small satellites into space, on a rideshare mission called Transporter-2.

The lull in launches could put a damper on SpaceX's plan to launch an estimated 40 rockets in 2021, most of which would ferry its own Starlink satellites into space. Unfortunately, necessary upgrades to the satellites took longer than expected, leading to a temporary launch hiatus. But now the company is back in business with a busy fall ahead, including the launch of the Crew-3 mission to the space station as well as Inspiration4, which will send four private citizens to orbit.

SpaceX relies on a fleet of reusable rockets in order to keep up a high launch cadence. This means that instead of using a brand-new rocket each time, the company can refly its recovered boosters many times over.

That's thanks to a set of upgrades the Falcon 9 received in 2018, as well as a fleet of drone ships to catch the returning boosters. 

SpaceX now has three of these massive ships: "Of Course I Still Love You," "Just Read the Instructions" and the newest ship on the block, "A Shortfall of Gravitas."

The company recently sent "Of Course I Still Love You" on a journey to the West Coast, where the boat will facilitate recovery operations for missions that launch from SpaceX's California-based launch pad at Vandenberg Space Force Base. 

After years of SpaceX CEO Elon Musk promising the arrival of a new drone ship, "A Shortfall of Gravitas" arrived at Port Canaveral on July 15. The massive ship is fully autonomous and even capable of driving itself out to the recovery zone where it will await returning boosters. (The company's other two ships have to be pulled by a tug.) 

For its first mission, ASOG was pulled by tug to the landing zone, where it made its first successful catch less than eight minutes after liftoff. 

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Amy Thompson
Contributing Writer

Amy Thompson is a Florida-based space and science journalist, who joined Space.com as a contributing writer in 2015. She's passionate about all things space and is a huge science and science-fiction geek. Star Wars is her favorite fandom, with that sassy little droid, R2D2 being her favorite. She studied science at the University of Florida, earning a degree in microbiology. Her work has also been published in Newsweek, VICE, Smithsonian, and many more. Now she chases rockets, writing about launches, commercial space, space station science, and everything in between.