“Saturday and Sunday could prove to be very similar to Wednesday’s weather,” said CNN meteorologist Haley Brink, referring to the postponed launch. “We may be waiting for a game time decision this weekend.”
The next launch opportunity is Saturday at 15:22 ET, with a 3 p.m. backup window. ET Sunday.
Scrubbing a pitch due to the weather is not uncommon.
“Scrubs are part of space flight safely and successfully. During my last mission on @Space_Station, time surprised us!” tweeted Bob Behnken, one of the two astronauts who will be aboard the Space Dragon’s Crew Dragon Capsule.
Experts distrust lightning
Lightning is a major concern for this weekend’s scheduled launch.
Pat Hyland, an associate researcher from the Cooperative Institute for Mesoscale Meteorological Studies (CIMMS) of the University of Oklahoma in support of the NOAA National Severe Storms Laboratory (NSSL), has spent several years researching precisely this topic. During his undergraduate and graduate research, funded in part by a NASA EPSCoR grant, he focused on investigating the electric field mill network (EFM) at the Kennedy Space Center to determine the false alarm rate and to help with NASA’s Lightning Launch Commit criteria.
“The motivation for the research was partly due to the fact that studies showed that over half of the lightning victims came from the first or one of the first flashes from cloud to earth (CG) in a storm and that a significant number of casualties stemmed from returning to outdoor activities too early, before the lightning had actually ceased, “Hyland said. “We were looking for potential models in what was happening with the surface electric field to provide driving hopes for lightning hazard warning decision situations, such as what happens to the Kennedy Space Center with their launches.”
They also tried to search for patterns in the atmosphere during their lightning experiments triggered by a rocket.
“This is another reason why, even in the absence of lightning strikes directly around the site, launches can sometimes be swept because rockets can artificially trigger lightning strikes,” said Hyland.
For example, lightning in the area will cancel a flight, as will a cloud with an electric field large enough to produce a flash triggered by a rocket. This happens when a giant spark of electricity occurs while a large rocket flies through a sufficiently strong electric field in the atmosphere.
The electric field needed to induce a flash triggered by a rocket is much lower than a natural lightning.
Other dangers could also rub the launch
Meteorologists also need to monitor the launchpad’s winds and weather downrange.
If there is a sustained wind of 30 mph or 162 feet above the launch pad, the mission will be blown away.
It’s not just the weather on the launch pad site. The Weather Squadron must also monitor the weather downrange because if the Crew Dragon Capsule encounters a problem, it must have a safe position for splashing.
An entire team of meteorologists is available from the 45th Space Wing and SpaceX to determine if the weather will mark the launch. Like Wednesday, the decision can be made until takeoff.
CNN’s Judson Jones contributed to this report.