For the third time this week, SpaceX and NASA are going to try to get a Cargo Dragon off the ground at Cape Canaveral. The spacecraft, loaded with roughly 6,400 pounds of science experiments, crew supplies, and station hardware, is now targeting a 6:05 p.m. EDT launch on Friday, May 15, after Florida’s spring storm season wiped out both earlier attempts. The new window is the last realistic shot before the mission would likely slip into the following week, stretching the timeline for biological investigations that depend on tightly synchronized ground controls running in parallel on Earth.
Two scrubs, one stubborn weather pattern
Tuesday’s attempt never made it off the pad. Launch teams stood down from Space Launch Complex 40 after forecasters flagged dangerous conditions in the area. A backup window on Wednesday looked marginally better: the U.S. Space Force’s 45th Weather Squadron had issued a 60% probability of favorable conditions, but anvil cloud rule violations forced a second stand-down before the countdown could reach its final minutes.
May at the Cape is notorious for this. Afternoon convective buildup, the towering thunderstorms that roll in from Florida’s interior nearly every day this time of year, creates exactly the kind of upper-level charge and cloud formations that trigger launch weather violations. Two scrubs in three days is frustrating but far from unusual during the peak of the pattern.
What’s riding on this launch
Dragon’s pressurized and unpressurized cargo spans dozens of investigations, but two stand out for their scientific ambition.
The first is ODYSSEY, a microbiology study that will track bacterial growth, biofilm formation, and horizontal gene transfer aboard the ISS under real microgravity. What makes ODYSSEY particularly sensitive to schedule slips is its experimental design: researchers are running parallel trials in Earth-based microgravity simulators that must stay in lockstep with the orbital phase. If the ground and space timelines drift too far apart, the comparison data degrades. Comparing results from orbit and from ground-based simulators is one of the investigation’s objectives, and a strong match could give future researchers a cheaper way to screen experiments before committing to costly station time.
The second is STORIE, a heliophysics instrument flying as part of Space Test Program Houston 11, a joint effort between the U.S. Space Force and NASA’s Goddard Space Flight Center. STORIE will map Earth’s ring current by capturing energetic neutral atom images from the station’s vantage point. The ring current intensifies during geomagnetic storms, and its behavior directly affects satellite electronics and ground-level power grids. More detailed ring current measurements could contribute to advances in space weather modeling, though the precise forecasting benefits will depend on how the data is integrated into existing prediction systems.
Beyond the headline payloads, the CRS-34 mission overview lists additional crew provisions and maintenance hardware, though NASA has not published a granular weight breakdown by individual experiment or supply category.
The Friday window and what could push it again
As of the Wednesday scrub announcement, the 45th Weather Squadron had not released an updated forecast specific to Friday’s window. The only public probability on record, that 60% figure, applied to Wednesday and proved optimistic. A fresh forecast is expected closer to launch day, but anyone planning to watch should treat the 6:05 p.m. EDT target as provisional until the day-of weather briefing confirms conditions are clear.
If Dragon does launch on time Friday, autonomous docking at the station is expected around 7 a.m. EDT on Sunday, May 17. That two-day transit means the crew likely won’t begin unpacking fresh experiments until late next week, a gap that grows with every additional delay. For time-sensitive studies like ODYSSEY, where ground-control protocols are already running, each lost day is not just an inconvenience but a potential hit to data quality.
SpaceX has not publicly identified the Falcon 9 first-stage booster assigned to CRS-34 or confirmed post-launch recovery plans for this attempt. NASA’s advisories state the vehicle is ready, but details about the booster’s flight history have not appeared in official materials.
Where to follow Friday’s CRS-34 launch attempt
NASA plans live coverage on NASA+ and its website starting before the launch window opens Friday evening. The most reliable move: check NASA’s CRS-34 mission page for a status update before tuning in. If a third weather scrub pushes the attempt into the following week, the delay would compound an already tight schedule for station-bound experiments that have been waiting since Tuesday to begin their journey to orbit.
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*This article was researched with the help of AI, with human editors creating the final content.
