Trump administration wants to pull funding for the International Space Station

The ISS will be supported till 2024, but its future after that is unclear

A draft budget proposal seen by The Verge shows that the Trump administration wants to end support for the International Space Station by 2025, leaving American astronauts grounded.

The first components for the ISS were launched two decades ago, in 1998, and it is expected to remain in operation until 2028. Although it is a massive investment, costing NASA between $3 and $4 billion each year, it is also a major tool for scientific research.

As well as experiments with microgravity, biology, physics, astronomy and meteorology, the ISS is used to test equipment and spacecraft systems required for deep space missions, to the Moon and Mars. It also acts as a platform for the Alpha Magnetic Spectrometer, which has been used to detect hints of dark matter.

An extension to the Station's funding in 2014 means that it will remain in operation to 2024, but its fate after that is ambiguous, with no firm decision from Congress. The commercial sector has encouraged NASA to extend operations to 2028, after which the ISS could be taken over by private companies. However, they may not be ready to do this by 2024.

Although the work on the ISS has made a great contribution to humanity's understanding of space, it is a massive drain on NASA's (static) budget. Ending support would free up resources for other work, such as the Space Launch System, the Orion crew capsule or the recent directive to return NASA astronauts to the moon, signed by the President last year.

On the other hand, cancelling the ISS without a replacement could lead to ‘a gap of human activities in lower Earth orbit', with fewer opportunities to train astronauts and test essential systems. Commercial companies like SpaceX and Boeing, which already use the Station for testing, won't be ready to send astronauts up until 2019 at the earliest.