Target Star Catalog
As we search for Earth-like exoplanets, this guide lists stars for astronomers to target for future scrutiny — candidates that might be suns shining on their own habitable worlds.
This catalog contains some of the most promising stars to explore with a mission such as the Habitable Worlds Observatory. Recommended by the National Academies of Sciences, Engineering, and Medicine as NASA’s next large space telescope, after the Nancy Grace Roman Space Telescope in 2027, the Habitable Worlds Observatory will be the first observatory built specifically to search for and directly observe Earth-like exoplanets, and study them for signs of life.
As planned, HWO will be able to peer into the habitable zones of nearby stars — the zone in which temperatures allow liquid water to exist on a planet’s surface, also known as the “Goldilocks zone.” The stars on this list qualify as “just right” for a mission like that to target — they have habitable zones far enough from the star so the telescope can get a clear view of any planets, and any Earth-sized exoplanet located there would be bright enough to allow spectral analysis of its atmosphere. This target list is expected to evolve as astronomers continue studying these stars, and can help inform the development of a future target list for the Habitable Worlds Observatory as planning for the mission progresses.
For each star listed below, the image (artist’s concept) links to an interactive 3D representation of the star. When you get to that detail page, learn more about the star’s exploration history and appearances in pop culture by selecting the plus sign next to the star’s name.
Filters
key to star types (artist concepts)
Yellow-White
F-type stars are yellow-white, and are somewhat hotter, more massive, and more luminous than our Sun.
Yellow
Type G stars — like our Sun — provide a wider habitable zone than some other types, but are relatively uncommon. Only about 6% of the stars in the Milky Way fall into this category.
Orange Dwarf
K-type, or orange dwarf stars are smaller and cooler than G-type stars like our Sun, but are three times more plentiful in the Milky Way, and can burn steadily for tens of billions of years. That gives any exoplanets more time to evolve life.
Red Dwarf
M-type stars, or red dwarfs, are abundant and long-lived, but also small, cool, and too faint to see with the unaided eye. These have a comparatively narrow habitable zone, very close to the star.
