
The most flight-seasoned Falcon 9 booster ever to be entrusted with a mission to the International Space Station (ISS) is ready for liftoff tonight from historic Pad 39A at Florida’s Kennedy Space Center (KSC).. Veteran B1073—making her seventh career launch and her second voyage in 2023, which flew as recently as last month—will give the Space Coast after sunset a new, temporary sunrise at 8:30 pm EDT, as he brings a twice-used Cargo Dragon loaded with nearly 6,300 pounds (2,850 kilograms) of equipment, cargo and station supplies for the current Expedition 68 crew.
Tonight’s mission is expected to kick off as many as three back-to-back Falcon 9 flights from the East and West Coasts over several days. If all goes well, another pair of rockets could lift off from Space Launch Complex (SLC)-4E at Vandenberg Space Force Base, Calif., and the storied Space Launch Complex (SLC)-40 at Cape Canaveral Space Force Station, Fla.on Thursday and Friday, respectively loaded with a “stack” of Starlink low-orbiting internet communications satellites and the dual-mounted SES-18 and SES-19 geostationary payloads for Luxembourg-headquartered satellite communications provider SES.
Weather conditions for tonight’s CRS-27 mission—which flies under an extension of the second-round Commercial Resupply Services contract between SpaceX and NASA—seems weak at first, with about a 50-50 chance that Mother Nature will smile on it. It has begun to increase, with an 80-percent chance of acceptable weather tonight, reaching 95 percent for Wednesday’s 8:08 pm EDT “immediate” backup chance and 90 percent for third test on Thursday.

“A strong jet stream to the north and an approaching mid-level disturbance moving down the Western Gulf of Mexico will both enhance the mid- and upper-level cloud cover flowing in from the west,” said the 45th Weather Squadron at Patrick Space Force Base at the briefing this Monday afternoon. “These clouds will be the main launch weather tonight, with the potential for Thick Cloud Layer Rule violations if cloud bases drop below 18,000 feet (5,400 meters).
“The disturbance will move east of the area on Wednesday, clearing the sky as the surface high center moves across the Eastern US,” it added. “As a result, no weather is expected for the backup window on Wednesday night.

“The next cold front will move into the Gulf of Mexico on Friday night, with an increasing pressure gradient ahead of the system, bringing strong and gusty south-southeast winds for a 72-hour delay,” concluded the 45th. “Any rain is expected to reach the area after the Friday night launch window; however, strong winds will cause Liftoff Wind concern.”
It will be SpaceX’s 17th mission in the 11th week of 2023, an average of launching once every 4.2 days. It will also be the fourth Falcon 9 to fly this month, following Crew-6’s ascent to orbit last midnight. on 2 Marcha Starlink-laden flight out of Vandenberg less than 40 hours later and third mission last week on behalf of OneWeb based in London, England.
In preparation for the launch and recovery of B1073, the Autonomous Spaceport Drone Ship (ASDS), “A Shortfall of Gravitas”—which successfully recovered four Falcon 9 cores this year—put to sea out of Port Canaveral on Sunday, to a position offshore in the Atlantic Ocean. The booster itself entered service in May of last year and has so far raised 157 Starlinks, the SES-22 and Amazonas Nexus geostationary communications satellite and a mission bound to the moon along with Japan’s Hakuto-R lander, the United Arab Emirates (UAE) Rashid rover and NASA’s water-ice-seeking Lunar Flashlight.
Flying its seventh mission tonight, B1073 became the most flight-seasoned Falcon 9 to carry cargo—people or cargo—to the ISS. The CRS-25 Cargo Dragon last summer and the historic, all-civilian Ax-1 mission last April for Houston, Texas-headquartered AxiomSpace, Inc., aboard the Dragon Endeavorboth flew over five-times-flown boosters, the current record.

Yesterday, following the conclusion of the CRS-27 Launch Readiness Review (LRR), NASA’s Phil Dempsey, transportation integration manager for the ISS Program, explained that there is a set of “criteria that we use…to evaluate the part of a booster” , as part of the decision process in selecting one for flight. He added that the decision was “based on an assessment of the health of a follower” and not on the number of previous missions.
Assuming an on-time launch at 8:30 pm EDT Tuesday, B1073 will power the Falcon 9 upward in the first 2.5 minutes of ascent, under 1.5 million pounds (680,000 kilograms) of thrust from its suite of nine Merlin 1D+ engines. The core will then separate from the stack to arrive on the ASOG deck about 7.5 minutes after launch.

Then comes the turn for the second stage’s single Merlin 1D+ Vacuum engine, which will fire for about six minutes to deliver the Cargo Dragon to its initial orbit. Eleven and a half minutes after leaving Florida, CRS-27 will separate from the Falcon 9 and at T+12 minutes and 22 seconds its nose cone will autonomously deploy, exposing its rendezvous sensors and other more hardware for the 36-hour chase. of the station, ahead of Thursday’s 7:52 am EDT docking at the forward port of the Harmony node.
In preparation for the cargo ship’s arrival, the current Expedition 68 crew—Commander Sergei Prokopyev and fellow Russian cosmonauts Dmitri Petelin and Andrei Fedyayev, along with US astronauts Frank Rubio, Steve Bowen and Warren “ Woody” Hoburg, along with Sultan Al-Neyadi of the United Arab Emirates (UAE)—were tasked with a range of activities to prepare the station. A robotic survey of the integrity of the Multi-Layered Insulation (MLI) on the forward International Docking Adapter (IDA) was completed on Monday, with CRS-27 cargo operations review and On-Board Training (OBT) using Robotics On- Also planned the Board Trainer (ROBoT).

After docking, CRS-27 will remain on the ISS for “about a month”, according to Mr. Dempsey on Monday. Its 6,300 pounds (2,850 kilograms) of cargo included a raft of scientific experiments, from heart health to the survivability of radioresistant bacteria, moss spores, amino acids and peptides in microgravity and from a camera ball clamp designed by will study up to a suite of eight technology experiments flying for the Space Systems Command (SSC) under the Space Test Program (STP) banner.
In addition to research hardware, the Cargo Dragon—which completed its Final Cargo Load last night—is also carrying Extravehicular Activity (EVA) tools, vehicle equipment and “some different cheeses” and fresh fruit, including apples, blueberries, grapefruit, oranges and cherry tomatoes for the Expedition 68 crew. Undocking is tentatively targeting mid-April, with NASA outlining that the long-awaited Crew Flight Test (CFT) of Boeing’s CST-100 Starliner will now fly No Earlier Than (NET) on April 30, with expectations that some “open-work” ” items could push the mission later in the summer.

Although SpaceX is showing precious little in terms of a forward manifest, it is expected that two more missions are waiting in the wings for their own launch in the coming days. Falcon 9 will lift a Starlink payload out of Vandenberg into an orbit of 350 miles (570 kilometers), inclined 70 degrees to the equator, as early as Thursday morning, followed by another booster with a dual-stacked SES-18 and SES-19 geostationary communications satellite from the Cape on Friday night.
Built by Northrop Grumman Corp. , SES-18 and SES-19 are equipped with ten C-band transponders and utilize the capabilities of its GeoStar-3 “bus”. These two satellites are part of a group of four SES birds—of which the first pair, SES-20 and SES-21board the United Launch Alliance (ULA) Atlas V to orbit early last fall—to lead an ongoing campaign to accelerate SES’s C-band clearing plan and meet the Federal Communications Commission’s (FCC) goal of freeing up spectrum for 5G terrestrial wireless service.

Back in June 2020, SpaceX was selected as the launch provider for SES-18 and SES-19. These two new satellites will help facilitate the delivery of digital television broadcasts to nearly 120 million homes.
Weather conditions for a Friday launch are about 70-percent favorable, the 45th Weather Squadron said in an update Tuesday, with a risk of violating the Liftoff Winds Rule. Conditions are forecast to worsen to just 35-percent-favorable for a backup attempt on Saturday, as a cold front whips a path toward Florida, bringing a pattern of disturbed weather, including showers, thunder and lightning.