ORLANDO, Fla., June 12 (UPI) -- SpaceX plans to expand the company's historic Starlink constellation with the launch of 58 more satellites from Florida on Saturday morning.
The payload is to lift off aboard a Falcon 9 rocket at 5:21 a.m. EDT from Cape Canaveral Air Force Station, which is adjacent to Kennedy Space Center.
The launch will be the ninth regular Starlink mission, boosting the number of Starlink satellites in orbit to 538 -- the most ever for any such constellation.
The launch is unique in that SpaceX planned to put sunshades on all the Starlink satellites as part of the company's effort to make them less visible from the ground.
Astronomers and other sky gazers have complained that bright reflections from the satellites can ruin observations of the heavens.
The rocket also will carry three SkySat satellites for the San Francisco-based space company Planet, formerly branded as Planet Labs, and represents the first launch for SpaceX's SmallSat rideshare program.
Planet was founded in 2010 by ex-NASA scientists Will Marshall, Robbie Schingler and Chris Boshuizen, with a goal to use space to enhance life on Earth. The company said it has over 100 satellites in orbit -- some the size of a shoebox -- collecting almost 100 million square miles of imagery daily.
Elon Musk's SpaceX routinely launches 60 Starlink satellites at a time, but packing the three other satellites into the nose cone means this launch will carry two fewer Starlinks.
The SkySat spacecraft are part of Planet's Earth-imaging constellation. The company provides surveillance and images of the planet's surface, updated frequently for emergency service providers, security and other customers.
SpaceX said the Starlink satellites still might be visible at certain hours when they reflect the sun in the week after launch. The company will make the spacecraft tilt their smallest side toward the sun to minimize reflection.
"We are working on implementing this as soon as possible for all satellites since it is a software change," according to a statement published on the company's website.
The company also intends to post information about the location of all Starlink satellites on tracking website Space-Track.org, to help astronomers schedule observations.
The first-stage booster on Saturday's mission previously traveled twice into space, carrying cargo in Dragon capsules to the International Space Station.
Liftoff is scheduled at the Air Force station's Launch Complex 40. The Air Force crew that produces weather forecasts for the launch will be all-female -- the first time in history, according to the Air Force.
A 70 percent chance of good launch weather will exist Saturday morning, with a 60 percent chance of good launch weather Sunday as a backup date in case of delays.