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Exoplanetary Scratchpad

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Alpha Centauri is also known as Rigil Kentaurus. A is also known as HD 128620 and HR 5459, B is HD 128621 and HR 5460, and C is Proxima Centauri. It is the nearest star system to the Sun. Contains a yellow dwarf star a little bigger than the Sun and an orange star a little smaller orbiting each other orbiting each other about the distance Uranus is from the Sun (varies from Saturn like to Neptune like), as well as a distant Red Dwarf companion Proxima that may or may not be orbiting the other two.

    Stellar fingerprinting suggests a high probability that a planet orbits star A, due to dearth of Iron around star. Russian astronomers announced the detection of a second planet orbiting the binary pair at 80 AU with a 100 year period, which appears to be false. The stars in the system will become markedly closer together in 2016, making observations much more difficult and one follow up failed to find it. The system is the first target for the European Cheops exoplanet space telescope.

    A planet was thought to have been discovered around star B and detected by HARPS. It would have been an Earth-massed rocky-iron planet with no atmosphere at epistellar distances around the orange dwarf star B. This would have been the least massive planet found around a sunlike star. The planet was informally and controversially named by Uwingu during a fund raising naming contest Albertus Alauda, after a participant's grandfather. Earthlike planets are not detectable in the habitable zone with present radial velocity methods. Technique for detection of planet is a source of doubt for some and it has yet to be independently verified. A team thought they might have detected a transit of this planet, but further observations showed the timing wasn't consistent. It is possible that a second further out (20.4 day period) Earth-sized planet is altering the transit times of the first. A cheap crowdfunded satellite devoted to studying this star could confirm the planets. The star was observed to be a good candidate to host a "super Habitable" planet, which would have 25% more gravity than the Earth, shallow seas, flatter landscape, higher atmospheric pressure, and the 6 BYO star would be stable for life longer.

    Proxima, a small flare star, was discovered in 1915 by Robert Ines, who named it. Long suspected planet around Proxima found not to exist. The Pale Red Dot project is dedicated to finding a planet around Proxima using dopplar spectrometry. As Proxima passes in front of two stars (once in 2014, again in 2016), any planets within 5 AU should be detectable via microlensing using the HST. It is known that no planets of Neptune sized mass exist within 1 AU and no Jovians with periods up to 1000 days, or transiting planets exist. An Earth-like planet in the habitable zone was discovered around Proxima Centauri. In 2017, a large stellar flare erupted and bombarded the planet, making it likely that the atmosphere has been completely stripped away by events such as this and not a good candidate for life. It was thought that a lot of dust existed in the system, making it feasable that the star had a rich complement of planets, but this seems to not be the case.

My Thoughts[]

It would be reeeally sweet if planet Ba turned out to be real, and even sweeter if the transit timing detected planet were real. Do we really need a satellite dedicated to observe this one star? A fleet of satellites observing a bunch of stars would be pretty neat. The relative positions of the two stars makes it so that you can only study it well in certain seasons. I hope we don't run into a bad season before we're able to confirm what we want to know. Just don't call the planet Albertus Alauda. I'm all for doing a nod to this name though, something kinda similar which is officially named after something else.

Alpha Centauri System Web Pages[]

Alpha Centauri System In the News[]

Initial Target for Proposed ExoplanetSat (Dec 2011)[]

Stellar Fingerprinting Suggests Possibility of Earthlike Planet Around Star A (Oct 2012)[]

Hot Rocky Planet Discovered Around Star B(Oct 2012)[]

Potential Target for Project Icarus Interstellar Exploration Mission (Oct 2012)[]

Top Target for Cheops (Oct 2012)[]

Cool Layer Found in Star A's Atmosphere (Feb 2013)[]

Uwingu Informal Naming Contest (Mar 2013)[]

Some Doubts on Planet (May 2013)[]

Star Occultation Allows Microlense Search for Proxima Planets (Jun 2013)[]

Star B A Good Place for a Super Habitable Planet (Feb 2014)[]

Planet Ab Not Detected (Apr 2014)[]

Star A Likely Harbors Rocky Planets (Aug 2014)[]

Second Planet Detected by Russians (Sep 2014)[]

Cannot find a second news source for this announcement

Evidence Planet Orbit b Not Viewed Face On, Put Limits on Mass (Mar 2015)[]

Transit Timing Variation Reveals a Second Planet? (Apr 2015)[]

How To Find Planets Around Binaries (Jan 2016)[]

Pale Red Dot Hunts for Planets Around Proxima (Jan 2016)[]

Potentially Habitable Planet found around Proxima (Aug 2016)[]

Proxima Flare Blasts Planet b (Mar 2018)[]

See Also[]