Project OAKTREE stands for Observations And Knowledge with Targeted Reconnaissance of Earth-like Exoplanets. It has the goal to characterise all nearby star systems within twenty light years and enhance observational programs.
The project is directed by Rob Swinney. Currently it is an activity to catalogue data, which is stored on the members only pages under Stellar Catalogue, but eventually it is the aim to move towards actual astronomical observations.
There are various characteristics which help to distinguish one star from another, depending on its structural type and position within its evolution. Some such as the mass and radius (equatorial) are self evident and are typically quoted relative to the Sun. However, some require some minor explanation as follows
Apparent magnitude: This is a measure of the brightness as seen by an observer on Earth. The brighter the object, the lower its magnitude value. It is a logarithmic measure so that a difference of one in magnitude would correspond to a change in brightness of around 2.5.
Absolute magnitude: This is a measure of the intrinsic brightness of an object, for a hypothetical observer that was positioned exactly 10 parsecs (32.6 LY) from the source. The brighter the object the lower the absolute magnitude.
Parallax: This is the apparent shift in position of the star against the background as seen from two different Earth based positions. It is measured in arcseconds and is given by 1/d(pc) where d(pc) is the distance in parsecs, where 1 parsec = 3.26 LY.
This following is a list of the nearest stars within 20 light years that we could plausibly travel to in the future. They are listed in order of increasing light years distance from Sol. This encompasses approximately around 100 different stars.
Single star system
- Distance 0 LY, spectral type G2 main sequence
- Mass 1.988E30 kg (Ms), Radius 695,700 km (Rs)
- 8 known planets
- Apparent magnitude -26.74, Absolute magnitude 4.85
- Parallax N/A