• Simma Sky: TESS and a New Planet like Earth

    By: Corey Simma

    Updated:

    JACKSONVILLE, Fla. - This edition of Simma Sky focuses not on what you can see up in the night sky this month...but what SOMETHING has seen in the sky the last year. NASA deployed TESS: the Transiting Exoplanet Survey Satellite last year and it spent the last 12 months searching for new planets. It found at least 28. According to Sky And Telescope, TESS was launched in April 2018 and was designed to find planets near bright stars within 200 light years of earth. It has four cameras that can monitor a 24 degree by 90 degree strip of the sky at a time. A great video description can be found here.

     
    Many parts come together for TESS to operate. Image credit NASA GSFC

    It should be noted that TESS was launched on a Falcon 9 rocket from Cape Canaveral. Florida sent this thing up. BOOYAH.


    Photo Courtesy MIT. The orbit sequence for TESS: first, a parking orbit (green), followed by a phasing orbit (yellow) with a lunar gravity assist which puts TESS into its final orbit (red), which is in a 2:1 resonance with the Moon (orbit in white).

    TESS has to occupy a position and orbit that isn't in a hostile space. It's scanning the sky for two years, after all...it needs some room to do its thing. NASA sent it up far enough away that the moon won't have an affect on it.

    So...what did TESS find? As of the beginning of August, TESS discovered 993 planet candidates in 12 of its 13 southern hemisphere scans (it did the south in its first year and will do the north in its second year). Obviously not all 993 of those candidates are actually planets and/or will become planets. The count of confirmed exoplanets is 28, as mentioned above. An exoplanet is a planet outside the solar system, in case you needed a refresher. NASA and other media outlets say that these exoplanets are detected by TESS training its camera on a star...and watching for the star to "blink." That "blink" is something - like an exoplanet - moving in front of it and blocking it momentarily. Pretty cool if ya ask me.

    GJ-357 was one of the later systems announced in the preliminary findings, which is notable because it's within this system that TESS may have discovered a planet like Earth. GJ-357d is 31 light years away from Earth, which is a hop, skip, and a jump away compared to some other findings. CBS News reports that GJ-357d is 6-times the size of Earth.

    According to Sky and Telescope, GJ-357d and two other exoplanets orbit a dwarf star. And GJ-357d is in what is known as the "Habitable Zone," or the zone conducive to allowing liquid water on the surface of said planet if the world is rocky and has an Earth-like atmosphere. Scientists from Cornell say that GJ-357d could be a "Bright" planet, meaning in this case, given high resolution imagery, would be able to determine if the planet has an atmosphere and the make-up of its atmosphere. You truly can't make this stuff up, folks. There may be life somewhere else OUTSIDE of the solar system.


    Illustration depicting one interpretation of the exoplanet GJ 357d. Image credit: Chris Smith / NASA's Goddard Space Flight Center.

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