5 comments on “This Week in Science

  • @OP – link – Pale Red Dot campaign reveals Earth-mass world in orbit around Proxima Centauri

    It should be remembered, that only a very small percentage of Earth-mass exoplanets are likely to be Earth-Type planets!

    Although Proxima b orbits much closer to its star than Mercury does to the Sun in the Solar System, the star itself is far fainter than the Sun. As a result Proxima b lies well within the habitable zone around the star and has an estimated surface temperature that would allow the presence of liquid water.

    However, the temperature could vary according to the nature and composition of any atmosphere on the planet.

    Despite the temperate orbit of Proxima b, the conditions on the surface may be strongly affected by the ultraviolet and X-ray flares from the star — far more intense than the Earth experiences from the Sun [4].

    Red Dwarf Stars are very prone to massive flares giving off radiation which is damaging to life.

    Two separate papers discuss the habitability of Proxima b and its climate. They find that the existence of liquid water on the planet today cannot be ruled out

    “Cannot be ruled out”, is far from confirming actual presence.

    and, in such case, it may be present over the surface of the planet only in the sunniest regions,

    With a very dim Red Dwarf parent star, much of the planet will be very cold. – Especially the dark side!

    either in an area in the hemisphere of the planet facing the star (synchronous rotation) or in a tropical belt (3:2 resonance rotation).

    The likely synchronous rotation, keeping one face towards the star (as with one side of our Moon facing Earth), there is likely to be a massive contrast in the temperatures between the daylight star-facing side, and the dark side.

    Proxima b’s rotation, the strong radiation from its star and the formation history of the planet makes its climate quite different from that of the Earth, and it is unlikely that Proxima b has seasons.

    Its synchronicity and very short year (of only a few Earth-days), would give a quite weird climate!

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  • I look forward to this as well DWH but only read a couple today and space the rest throughout the week because as much “stuff” as there is on net, good content can be scarce.

    One I read tonight was the fish oil piece, hoping it held the answer to safely increasing my bacon intake. In a way it did but in this world of unintended consequences, I have to wonder what my tolerance to mercury might be.

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  • Alan4discussion #3
    Aug 28, 2016 at 12:31 pm

    It is however promising, that exoplanets are being found in this close a proximity to Earth!

    It is also promising that there are icy bodies very far out in the Solar-System which could be mined for their water by robots, and used for fuel processing plants and refuelling stations, for inter-stellar craft or probes.

    Astronomers in the US have uncovered previously unknown objects in the outer reaches of the Solar System.

    They include an icy body with an orbit that takes it so far from the Sun that it is probably influenced by the gravity of other stars.

    The discoveries were found during an effort to locate a possible ninth planet, whose presence has been inferred indirectly.

    The study is set to be published by The Astronomical Journal.

    Co-authors Scott Sheppard and Chad Trujillo have submitted the details of their discoveries to the Minor Planet Center, which catalogues such objects, along with asteroids and comets.

    Their search was carried out using several observatories around the world, including the the four-metre Blanco telescope in Chile and the eight-metre Subaru telescope in Hawaii.

    One of the new objects, known for now as 2014 FE72, is the first distant Oort Cloud object found with an orbit entirely beyond Neptune.

    Its orbit takes it some 3,000 times further than the Earth is from the Sun.

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