There’s a lot riding on the next flight of the Falcon 1 rocket, built by the private rocketeers at Space Exploration Technologies (SpaceX).

The earliest possible time for the first countdown attempt of Falcon 1 (not necessarily launch) is projected to occur sometime between June 26 and July 7 at liftoff central from the Kwajalein Atoll in the Marshall Islands. That’s the same departure site for two previous rocket shots of the vehicle that failed to showcase an orbital capability.

“However, until we complete the static fire and have a chance to analyze data, please assume that there is not even an official launch date range,” Elon Musk, chief of SpaceX told me today via email. He said that the launch date for the Falcon 1’s third flight is not known at this time.

This next rocket flight is loaded with payloads, including a mission of the U.S. Department of Defense Operationally Responsive Space Office (ORS), dubbed Jumpstart - SpaceDev’s Trailblazer spacecraft bus.

Also onboard is other gear, such as NASA and Cornell University hardware, as well as 208 memorial spaceflight participants, the largest number of “cremains” carried spaceward as part of the Celestis Explorers Flight program.