But it will take years to wait for the rocket, and the inspector-general believes that a switch to another launch vehicle already in use could save taxpayers up to $1 billion.
It is reported that NASA's current plan is to officially release the Europa mission probe in 2023, when it will provide ground scientists with the nearest image to the satellite.
In fact, the mission, Europa Clipper, has attracted widespread attention in Congress, especially John Culberson, a former congressman who is a big fan of Europa and has identified funding sources for the project over the past decade.
It is understood that one way Culberson can secure funding is to link the launch of the mission to SLS, which has a very strong support group in Congress.
SLS's first flight was planned for 2017, but was delayed for various reasons. Now, it may have to wait until 2021 for its first (non-manned) flight, and the next flight is planned to take place in about two years, when it will become its first manned flight.
This delay has brought trouble to the Europa Fast Sailing Mission. In a letter to members of Parliament responsible for funding the agency, NASA Inspector General Paul Martin pointed out that all this meant that Europa's mission would not take place until 2025 at least. If NASA had to use SLS on the Europa Fast Sailing mission, that would mean that the probe would probably need to be idle on Earth for two years, and its monthly maintenance costs would range from $3 million to $5 million. In addition, even if the SLS is ready in some way by 2023, the detector may still need to be stored. Because Earth and Jupiter will align in 2023, and there will be only one very small window in July of that year. However, Europa Fast Sailing may not be launched until late 2023, so that means it will miss this window and have to wait for the next opportunity.
In addition to SLS, the Europa Fast Sailing Mission actually has two other options - SpaceX's Falcon Heavy and ULA's Delta IV Heavy. Among them, the Delta IV Heavy rocket has been in operation for 15 years, and the Falcon Heavy Rocket has carried out three launches -- enough to meet NASA's minimum requirements for the Europa mission. In addition, the analysis of Europa Fast Sailing Mission shows that the cost of SLS will be 700 million dollars higher than any of the above schemes.
The only advantage of SLS is its powerful power. If launched through SLS, the probe would take only 2.4 years to reach Europa, while a less powerful commercial rocket would take nearly six years. But NASA is considering upgrading the Falcon Heavy Rocket, which will help shorten flight time. More importantly, these commercial rockets are ready, and everything depends on when the Europa Express is ready.
Martin said Congress needed to make changes and must do so now. If commercial rockets were to be used, the process would have to start in the next few months to meet the 2023 deadline.