A couple of days ago, Astro Orbiter unexpectedly closed in Tomorrowland at the Magic Kingdom. It is unclear if this shutdown took place due to unexpected maintenance or if this is part of a wider transformation of Tomorrowland. You may note that the main entrance sign into Tomorrowland has temporarily disappeared and a new marquee is expected to debut very soon.
Astro Orbiter is currently scheduled to be closed until August 14th. The ride is expected to reopen to guests as normal on August 15th. Please keep in mind that unplanned refurbishments such as this one, could change reopening times at any point. It is always best to double check with Cast Members while visiting or refer to the My Disney Experience app to check the status of this or any attraction.