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Ephemeris: 04/07/2025 – Does the nearest star to our Sun have a habitable planet?

April 7, 2025 Comments off

This is Ephemeris for Monday, April 7th. Today the Sun will be up for 13 hours and 6 minutes, setting at 8:18, and it will rise tomorrow at 7:10. The Moon, 3 days past first quarter, will set at 5:38 tomorrow morning.

The closest star to our sun is Proxima Centauri which is a small member of the Alpha Centauri star system. It is a red dwarf star and has, we think, at least three planets. They are designated b, c and d. And right now “c” is questionable. At least one of these planets is in the habitable zone of the star, based on the amount of heat this little star gives off. So these planets all quite close to the star, and the problem with Proxima and with most red dwarf stars is that they create a great number of what we call solar flares. When the Earth gets hit by a solar flare from 93 million miles it causes the Northern Lights and causes X-rays to flood the Earth which is mostly shielded by the ozone in our atmosphere. These planets are much closer to their star.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

A diagram of the Proxima Centauri planetary system as we think we know it now
This is a diagram of the Proxima Centauri planetary system as we think we know it now. The diagram assumes circular orbits. The planets are labeled in the order of being found, even if not confirmed, which is why b has a larger orbit than d, all of which have smaller orbits than c. The only confirmed planet is b, which orbits the star in 11 days, and lies at 4.7 million miles (7.5 million kilometers) from it. The distance units are in AU, which are astronomical units, a standard within planetary systems. One AU equals the distance of the Earth to the Sun, therefore Proxima Centauri c has an orbit about the size of Mars’ orbit of the Sun. Instead of taking a bit less than two years to orbit the star like Mars, it takes over five years. Credit: Universe Space Tech.
The star field containing Proxima Centauri
The star field containing Proxima Centauri, including Alpha and Beta Centauri. Hadar (Beta Centauri) is itself a triple star system, but 361 light years away. Image credit: Skatebiker at English Wikipedia, annotations, except for the Proxima finder circle, by the author.
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