Nova | American Astronomical Society | 2016 Apr 20
[img3="Artist’s illustration of an M-dwarf star surrounded by three planets. A recent study examines which stars make the best targets when searching for habitable exoplanets.M-dwarf stars are excellent targets for planet searches because the signal of an orbiting planet is relatively larger (and therefore easier to detect!) around small, dim M dwarfs, compared to Sun-like stars. But are there better or worse stars to target within this category when searching for habitable, Earth-like planets?
[Credit: NASA/JPL-Caltech]"]http://aasnova.org/wp-content/uploads/2016/04/fig17.jpg[/img3]
Radial velocity campaigns search for planets by looking for signatures in a star’s spectra that indicate the star is “wobbling” due to the gravitational pull of an orbiting planet. Unfortunately, stellar activity can mimic the signal of an orbiting planet in a star’s spectrum — something that is particularly problematic for M dwarfs, which can remain magnetically active for billions of years. To successfully detect planets that orbit in their stars’ habitable zones, we have to account for this problem.
In a recent study led by Elisabeth Newton (Harvard-Smithsonian Center for Astrophysics), the authors use literature measurements to examine the rotation periods for main-sequence, M-type stars. They focus on three factors that are important for detecting and characterizing habitable planets around M dwarfs:
- Whether the habitable-zone orbital periods coincide with the stellar rotation ...
- How long stellar activity and rapid rotation last in the star ...
- Whether detailed atmospheric characterization will be possible ...
The Impact of Stellar Rotation on the Detectability of Habitable Planets Around M Dwarfs - Elisabeth R. Newton et al
- Astrophysical Journal Letters 821(1):L19 (10 Apr 2016) DOI: 10.3847/2041-8205/821/1/L19
arXiv.org > astro-ph > arXiv:1604.03135 > 11 Apr 2016