Musings on the nearest star

If you or I had a spare 75,000 years and a few trillion dollars set aside, we could try journeying to the closest star beyond the Sun, Alpha Centauri. Some 4.3 lightyears away, this triple star system is more representative of stars in the galaxy than our loner Sun. Alpha Centauri consists of a bright double star, Alpha A and Alpha B, and a distantly orbiting red dwarf called Proxima Centauri, which is a shade closer to us at 4.2 light-years.

Alpha Centauri is one of the most brilliant stars in the southern sky, shining at magnitude 0. It is prominently visible to the naked eye as the luminary of Centaurus, nestled near the bright constellation Crux the Southern Cross.

Of the double star components, Alpha Cen A is a sunlike star that is slightly larger and more luminous than our star. Alpha Cen B is slightly smaller and dimmer than the Sun and also slightly more orange in hue. Proxima is a small, reddish star with only one-tenth the mass of the Sun, or 129 times the mass of Jupiter. Proxima orbits its two larger companions once every half-million years.

If you observe from the southern sky or get a chance to travel there, make sure you look at this trio of suns. They are a reminder of both the relative closeness of objects in the universe and its incredibly large distance scale