Our scientists are investigating how a UK-led team could design and build a core instrument for a flagship NASA mission to search for life on distant planets.
The Habitable Worlds Observatory (HWO) will be the first telescope specifically engineered to identify habitable, Earth-like planets and examine them for evidence of life.
It is expected to launch in the early 2040s, and our scientists are helping to develop a proposal for a high-resolution imaging camera that would form part of the mission.
The imager would be used to measure the planets' masses, and to inspect their atmospheres for the chemical fingerprints of life.
Rocky planets
Current observatories can find giant planets outside our Solar system – but these are inhospitable places more similar to Jupiter than Earth.
The Habitable Worlds Observatory would use an instrument called a coronagraph to block the bright glare of a host star.
This would allow scientists to see distant planets directly for the first time, including small, rocky planets more like Earth.
Habitable rocky planets orbit close to their star, but are a million or more times fainter. Imaging them is like trying to see planets in our own solar system, at midday.
Using the coronagraph, scientists could directly study which molecules may be present in a planet's atmosphere – providing clues to whether the planet has life.
Water, oxygen or methane
The high-resolution imaging camera being scoped out by the UK-led consortium would then investigate any planets spotted by the coronagraph.
When a planet passes in front of its star, starlight has to travel through the planet's atmosphere.
Just as our Sun looks redder at sunset, the star will change colour slightly. Its spectrum can be studied for molecules, such as water, oxygen, or methane, providing clues to whether the planet has life.
As a planet orbits its star, its gravity also moves the star slightly. By watching the movement of stars with unprecedented precision, the imager will measure the mass of the planet, and the strength of gravity faced by surface life.
Artist's rendering of three concepts for the Habitable Worlds Observatory. Credit UCL.
Studying other parts of the Universe
The mission will have time to study other parts of the Universe.
Habitable Worlds Observatory will be the 21st century's Hubble Space Telescope. As well as looking for life, a telescope that amazing will watch collisions of asteroids in our solar system, stare into black holes, and solve the mystery of dark matter.
The UK team is led by UCL and includes scientists and engineers from the University of Portsmouth, RAL Space (the UK's national space laboratory), and the UK Astronomy Technology Centre, as well as Durham.
It is one of two groups funded by the UK Space Agency to investigate the feasibility of a UK-led high-resolution imager, with the other group led by the University of Leicester.
