San Francisco, April 20 : SpaceX's Starship is ready for its first orbital test flight on Thursday, CEO Elon Musk said. This will be the second launch attempt, as the first on Monday was scrubbed at the last minute due to an issue with the pressurisation system on Starship's first stage, a huge booster called Super Heavy. "All systems currently green for launch," Musk wrote in a tweet on Thursday. Earlier on Tuesday, he tweeted that the company is working on many issues to prepare for the launch. "The team is working around the clock on many issues. Maybe 4/20, maybe not," Musk said. Meanwhile, the company updated on its website: "SpaceX is targeting as soon as Thursday, April 20 for the first flight test of a fully integrated Starship and Super Heavy rocket from Starbase in Texas." "The 62 minute launch window opens at 8:28 a.m. CT (6:58a-pm IST) and closes at 9:30 a.m. CT (8:00a-pm IST)," it added. If successful, the Super Heavy booster will make a hard splashdown in the Gulf of Mexico about eight minutes after liftoff today. Starship's upper-stage spacecraft will make a partial lap around Earth, coming down in the Pacific Ocean near Hawaii around 90 minutes after launch. "With a test such as this, success is measured by how much we can learn, which will inform and improve the probability of success in the future as SpaceX rapidly advances development of Starship," the company said. Musk had previously said that there is only a 50 per cent chance that the first-ever orbital mission of SpaceX's huge Starship vehicle will be a success. But he also stressed that SpaceX is building multiple Starship vehicles at the South Texas site. These will be launched in relatively quick succession over the coming months, and there's about an 80 per cent chance one of them will reach orbit this year. SpaceX aims to use Starship as a fully reusable transportation system to carry both crew and cargo to Earth orbit, help humanity return to the Moon, and travel to Mars and beyond. /IANS