The commercial revolution

The most transformative development in space exploration in the past decade has been the dramatic reduction in the cost of reaching orbit. SpaceX's development of the reusable Falcon 9 booster — which lands itself after launch and can be reflown within days — has reduced the cost of a kilogram to orbit from around $65,000 in the Space Shuttle era to under $3,000. This cost reduction has democratised access to space, enabling satellite constellations (Starlink), rapid iteration in spacecraft design and a wave of new space startups.

The James Webb Space Telescope

Launched in December 2021 after decades of development, the James Webb Space Telescope (JWST) has exceeded performance expectations. Observing in infrared, JWST can peer through gas and dust clouds that blocked Hubble's visible-light view, and can observe the most distant and therefore earliest galaxies in the universe. Its images have revealed galaxy formation happening earlier and in greater numbers than predicted by some models, challenging aspects of the standard cosmological model.

Artemis and the Moon

NASA's Artemis programme, in partnership with ESA, JAXA, the Canadian Space Agency and commercial partners, aims to return humans to the Moon and establish a sustainable presence — a lunar Gateway space station and potentially a surface habitat. The scientific goals focus on the lunar south pole, where permanently shadowed craters are believed to contain water ice that could be used for life support and fuel. SpaceX's Starship is contracted as the human landing system.

The Mars question

Both NASA and SpaceX have long-term ambitions for crewed Mars missions. The technical challenges are formidable: a minimum round-trip journey takes 18-21 months; Mars's thin atmosphere complicates landing; radiation exposure during transit is a serious health risk. NASA's timeline for crewed Mars missions is the late 2030s; SpaceX has been more aggressive in its public statements. The scientific case for sending humans (rather than robots) to Mars rests on the superior dexterity and adaptability of human researchers.