Elon Musk aims for first Starship hopper test flight in the next four weeks

Starship Hopper is a shorter version of the main Starship spacecraft, currently being assembled in Boca Chica, Texas

SpaceX CEO Elon Musk is aiming for the first test of the SpaceX Starship hopper, a shorter version of the upcoming Starship vehicle, in the next four weeks. According to Musk, the first hopper engine is being assembled in California and is almost complete.

"Aiming for four weeks, which probably means eight weeks, due to unforeseen issues," Musk said in a tweet on Saturday.

The test launch of Starship hopper will validate the design of the rocket, its performance at supersonic speeds, and its ability to deal with the cryogenic environment of space.

Earlier, Musk had revealed that the engines on the Starship hopper are a mix of Raptor development and operational parts, and that the Raptor engine for the Starship has been "radically redesigned."

In his tweet, Musk also shared a mock-up image of Starship vehicle, which is currently being assembled in Boca Chica, Texas. The picture shows the vehicle with a smooth metallic finish, but lacking windows. However, Musk has confirmed that Starship's final version will have windows.

This operational version will likely be 30 feet wide and much taller than Starship hopper.

The Starship vehicle is part of SpaceX's long-term plan for an interplanetary transport system. It was earlier named as Big Falcon Rocket (BFR), but in November, Musk renamed the massive rocket as Starship.

The spacecraft will be able to carry hundreds of tonnes of cargo into space. The construction cost of the spacecraft is estimated at $5 billion.

In December, Musk shared a picture of the Starship vehicle and revealed that it would be made out of stainless steel, like the Atlas rockets of 1950s, but would have different architectural style.

If everything goes as planned, SpaceX may start construction of a full-scale Starship spacecraft in late 2019 or early 2020. The vehicle will likely be ready to conduct its first cargo flight as early as 2022. Assuming all flights of the spacecraft are successful, SpaceX scientists may then plan the first lunar passenger flight by 2023.