To explore nearby Earth-like exoplanets, a fresh telescope design might be key. This new idea suggests using a rectangular mirror rather than the typical circular shape. Professor Heidi Newberg from Rensselaer Polytechnic Institute explains that this rectangular design could still capture images of planets similar to Earth while being about the same size as the James Webb Space Telescope (JWST).
Current discussions around new space telescopes, as outlined in the National Academies’ Decadal Survey, suggest designs with large round mirrors. The minimum size proposed is around 26 feet (8 meters) in diameter. While this design has potential, Newberg believes a rectangular mirror could offer a more practical solution.
If we want to spot planets with water vapor, the telescope needs to be optimized to view infrared light at a very specific wavelength of just 10 microns. The JWST has already shown it can detect water vapor in distant atmospheres, but it struggles to spot Earth-sized planets within the habitable zones of sun-like stars. A telescope large enough to do this would be prohibitively costly and complex to build.
Interestingly, Newberg’s team found that a rectangular mirror measuring 65.6 feet by 3.3 feet (20 meters by 1 meter) could be much more efficient. Not only is it simpler to create, but it may also be less expensive than working with gigantic circular telescopes or launching multiple small ones that would need to be precisely aligned.
This rectangular telescope would have a collecting area smaller than the JWST but would focus all its collection power directly on the target planet, improving efficiency. Newberg’s research indicates that such a telescope could locate around 30 Earth-like planets orbiting sun-like stars within just three years.
According to recent findings, there are about 69 sun-like stars and nearly 300 cool M dwarf stars within 32.6 light-years of Earth that might be worth studying. By honing in on these targets, the proposed telescope could substantially advance our understanding of potentially habitable worlds.
With technology continually evolving, this innovative design could lead to significant breakthroughs in space exploration. A paper discussing this concept was published recently in the journal Frontiers in Astronomy and Space Sciences.
These steps into the future could bring us closer to discovering new planets that share similarities with our own, sparking curiosity and excitement in the scientific community and beyond.
