Elon Musk has confirmed that SpaceX hopes to try "very short" launches or "hops" of a new spaceship prototype in Texas this week.

Called the "Test Hopper," the vehicle is a prototype of a more advanced, 400-foot-tall launch system called Starship, which SpaceX is designing to send people to Mars.

Musk also shared critical updates about Starship's heat shield, test-launch plan, construction timeline, and more.

This story has been updated with new information.

When updates about SpaceX's plans rain from Elon Musk, they tend to pour.

Such was the case on Sunday, when Musk — the rocket company's founder — opened Twitter to divulge the latest information about a roughly 40-story launch system called Starship.

The ultimate goal for the Starship system is to ferry up to 100 people and 150 tons of cargo to the surface of Mars. It's also being designed to be fully reusable, which may reduce launch costs by 10- to 100-fold (and further disrupt the launch industry).

But to prove the technologies required to get Starship into orbit will actually work, SpaceX has feverishly developed a prototype called "Test Hopper" at its launch site in southern Texas. The shiny steel vehicle can't reach orbit, and will instead just do short launches or "hops" of no higher than 16,400 feet (hence its name).

Over the weekend, following reports that SpaceX was preparing for its first hops this week, Musk took to Twitter to answer questions from his followers. In the process, he shared new details about the Test Hopper's launch testing, changes to Starship's heat shield, construction of orbital-class spaceships, and more.

Here are five of the most important things we learned.