A flyable prototype of SpaceX Starship -- the spacecraft that will one day take up to 100 humans to Mars on a single trip -- is expected to make its test flight debut by the end of August or early September.

SpaceX announced the ambitious maiden flight for Starship Mark 1, which is being built and tested at its spaceport in Texas. CEO Elon Musk revealed one or both of the company’s two orbital Starship prototypes might be “ready to fly” by the end of August if certain conditions are met.

Musk is notorious for being overly optimistic as regards deadlines, and some Musk watchers say this has every indication of being one of those times. But the event will be spectacular if Musk really lives-up to his word.

Standing nine meters tall and made from stainless steel, Starship is a fully reusable second stage and spacecraft. The massive first stage that will launch Starship into space is named Super Heavy.

Starship is designed as a long-duration cargo- and passenger-carrying spacecraft. SpaceX plans to launch commercial payloads aboard Starship by 2022 at the earliest.

Musk will reveal the latest about Starship on Aug. 24 at the SpaceX South Texas Launch Site, which is a spaceport and test site located at Boca Chica Village near Brownsville, Texas. The South Texas Launch site, which will be completed this year, will be used for the exclusive launch of Starship/SuperHeavy in the future.

As with a similar event in 2018, this year’s conference at Boca Chica will see Musk update the public on Starship, which is expected to land the first humans on Mars in the decade of the 2030s. This detailed review should be the most extensive yet about Starship.

SpaceX is also building and testing full-scale Raptor engines that will deliver Starship’s enormous planet-hopping power. Starhopper, the flyable prototype of Starship, saw an untethered hop debut on July 25.

Its second flight, a gutsy 200 meter (660 foot) hop, is scheduled for Aug. 12. Musk describes Starhopper as just a low-fidelity testbed.

SpaceX is currently building two orbital-class Starship prototypes simultaneously, one at Boca Chica and the other at Cocoa, Florida. These two prototypes currently consist of four separate pieces (two barrel sections and two pointed nose sections), each standing 45 meters to 50 meters tall if stacked together.