{"id":19064,"date":"2017-02-22T22:54:15","date_gmt":"2017-02-22T14:54:15","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/looking-for-life-scientists-find-7-possibly-earthlike-planets-orbiting-ultracool-star\/"},"modified":"2017-02-22T22:54:15","modified_gmt":"2017-02-22T14:54:15","slug":"looking-for-life-scientists-find-7-possibly-earthlike-planets-orbiting-ultracool-star","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/looking-for-life-scientists-find-7-possibly-earthlike-planets-orbiting-ultracool-star\/","title":{"rendered":"Looking for life: Scientists find 7 possibly Earthlike planets orbiting ultracool star"},"content":{"rendered":"<figure id=\"attachment_312281\" aria-describedby=\"caption-attachment-312281\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img fetchpriority=\"high\" decoding=\"async\" class=\"size-full-width wp-image-312281\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-3x-630x530.jpg\" alt=\"TRAPPIST-1 system\" width=\"630\" height=\"530\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-3x-630x530.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-3x-768x646.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-3x-1240x1043.jpg 1240w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-3x.jpg 1283w\" sizes=\"(max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-312281\" class=\"wp-caption-text\">A diagram shows seven exoplanets orbiting&nbsp;an ultracool dwarf star known as TRAPPIST-1. If the planets were transported to our own solar system, they\u2019d all lie within Mercury\u2019s orbit. (ESO Illustration)<\/figcaption><\/figure>\n<p>A second look at an exoplanet system 40 light-years from Earth has brought a bonanza for astronomers: not two, not three, but seven alien worlds \u2013&nbsp;some of which could have acceptable conditions for life.<\/p>\n<p>\u201cI think that we\u2019ve made a crucial step towards finding if there is life out there. \u2026 Before, it was indications,\u201d said study co-author Amaury Triaud of Cambridge University\u2019s Institute of Astronomy. \u201cNow we have the right target.\u201d<\/p>\n<p>That claim is debatable, but in any case, the discovery suggests that there are even more planets out there than astronomers previously thought. Which is what astronomers have been saying repeatedly for the past decade.<\/p>\n<p>\u201cThe solar system with its four (sub-)Earth-sized planets might be nothing out of the ordinary,\u201d Ignas Snellen of the Leiden Observatory wrote in a commentary on the findings, published in this week\u2019s issue of the journal Nature.<\/p>\n<p><iframe title=\"eso1706a\" src=\"https:\/\/www.youtube.com\/embed\/AxbH-5EZQak?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen=\"\" data-ratio=\"0.5625\" data-width=\"800\" data-height=\"450\" style=\"display: block; margin: 0px; width: 800px; height: 450px;\"><\/iframe><\/p>\n<p>The discoveries actually started last year, when the same team of astronomers reported spotting three Earth-sized planets around an ultracool dwarf star called TRAPPIST-1, in the constellation Aquarius.<\/p>\n<p>The star is only slightly bigger than Jupiter, and puts out about 0.05 percent as much light as our sun. It takes its name from the 23-inch telescope in Chile that the astronomers used to find it, known as the&nbsp;<span style=\"text-decoration: underline;\">Tra<\/span>nsiting <span style=\"text-decoration: underline;\">P<\/span>lanets and <span style=\"text-decoration: underline;\">P<\/span>lanetes<span style=\"text-decoration: underline;\">i<\/span>mals <span style=\"text-decoration: underline;\">S<\/span>mall <span style=\"text-decoration: underline;\">T<\/span>elescope or TRAPPIST.<\/p>\n<p>The team, led by&nbsp;Micha\u00ebl Gillon&nbsp;of Belgium\u2019s University of Li\u00e8ge, conducted follow-up observations with TRAPPIST and other instruments over the months that followed. They watched for repeated dimmings of the TRAPPIST-1 star as planets passed across its disk, and worked out the sizes as well as the masses of the planets by carefully monitoring the variations in the timings of the transits.<\/p>\n<p>The additional data showed that the pattern of sightings they associated with the third, outermost planet was actually being caused by three separate worlds. They also detected&nbsp;the signatures of two farther-out planets, bringing the total to seven.<\/p>\n<p>The planets are known as TRAPPIST-1 b, c, d, e, f, g and h. All of them lie within what would be the orbit of Mercury in our own solar system. But because the parent star is so dim, the e, f and g planets are in the system\u2019s habitable zone, where it\u2019s theoretically cool enough for water to exist in abundant liquid form.<\/p>\n<p>All seven planets are roughly Earth-sized, and planets b through g appear to be rocky planets like our own. Planet h is still a question mark, however, because astronomers don\u2019t yet have enough data to figure out its mass or its density.<\/p>\n<p><iframe title=\"PIA21430\" src=\"https:\/\/www.youtube.com\/embed\/_HfgHhMg6vY?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen=\"\" data-ratio=\"0.5625\" data-width=\"800\" data-height=\"450\" style=\"display: block; margin: 0px; width: 800px; height: 450px;\"><\/iframe><\/p>\n<p>Although TRAPPIST-1 isn\u2019t close enough to visit anytime soon, the newly published findings add some extra luster to the dim bulbs of the Milky Way. Ultracool dwarfs and red dwarfs are appealing targets because they\u2019re the most populous classes of stars in our galaxy, and because they\u2019re so long-lived.<\/p>\n<p>TRAPPIST-1 is thought to be at least a billion years old, and Gillon said it\u2019ll probably remain stable long after our own sun has run out of gas. The same forecast applies to Proxima Centauri, the 4.8 billion-year-old red dwarf that\u2019s only 4.2 light-years away from us and harbors at least one Earth-type planet.<\/p>\n<p>There are potential drawbacks, however: For one thing, the dynamics of TRAPPIST-1\u2019s planets suggest that they present the same face to the star all the time. That could bake one side and freeze the other, unless there\u2019s an atmosphere thick enough to even things out.<\/p>\n<p>For another thing, red dwarf stars occasionally unleash strong radiation flares that could blast away at a planet\u2019s atmosphere. A study published this month suggested that the loss of oxygen due to such blasts could significant reduce the chances for habitability.<\/p>\n<p>Gillon downplayed the radiation threat in TRAPPIST-1\u2019s case. \u201cIt has some flares, but they are not very strong, and it is quite rare,\u201d he said.<\/p>\n<figure id=\"attachment_312300\" aria-describedby=\"caption-attachment-312300\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full-width wp-image-312300\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170222-planets-630x354.jpg\" alt=\"Planet comparison\" width=\"630\" height=\"354\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170222-planets-630x354.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170222-planets-768x432.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170222-planets.jpg 1024w\" sizes=\"auto, (max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-312300\" class=\"wp-caption-text\">This chart compares the basic statistics for the TRAPPIST-1 planets with similar statistics for our solar system\u2019s rocky planets. Click on the image for a larger version. (NASA \/ JPL-Caltech Illustration)<\/figcaption><\/figure>\n<p>The key questions, then, have to do with what\u2019s in the atmospheres of the TRAPPIST-1 planets. Triaud said the team is already trying to figure that out, using the Hubble Space Telescope and other instruments.<\/p>\n<p>\u201cThe first stage that we are doing at the moment is a reconnaissance stage, where we are trying to rule out that the planets have a large hydrogen envelope. This is to make sure&nbsp;that the planets are indeed Earthlike,\u201d he explained. \u201cThis will then be followed by detailed observations to study the climate, and eventually, from the chemical information, trying to find if there is life over there.\u201d<\/p>\n<p>He hoped to get the answer to the life question \u201cmaybe within a decade.\u201d Reaching&nbsp;that goal depends on building bigger and better observatories, such as NASA\u2019s James Webb Space Telescope and the European Extremely Large Telescope.<\/p>\n<p>Gillon said determining the presence of life will require not only figuring out what chemicals are in the atmosphere&nbsp;\u2013 such as oxygen and water vapor, carbon dioxide and methane&nbsp;\u2013 but also figuring out their proportions. \u201cIt\u2019s really the combination of molecules,\u201d he said. \u201cOxygen itself is not enough.\u201d<\/p>\n<figure id=\"attachment_312289\" aria-describedby=\"caption-attachment-312289\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full-width wp-image-312289\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-landscape-630x354.jpg\" alt=\"\" width=\"630\" height=\"354\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-landscape-630x354.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-landscape-768x432.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2017\/02\/170221-planet-landscape.jpg 1024w\" sizes=\"auto, (max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-312289\" class=\"wp-caption-text\">This artist\u2019s conception paints a speculative picture showing what&nbsp;it might be like to stand on the surface of the planet TRAPPIST-1f. (NASA \/ JPL-Caltech Illustration)<\/figcaption><\/figure>\n<p>Although it\u2019s unlikely that humans will ever stand on TRAPPIST-1f or the other planets in the star system, it\u2019s intriguing to imagine what it\u2019s like there. Because the planets are so tightly packed, you could travel from one world to another in a matter of days using conventional spaceflight technology. No warp drive required.<\/p>\n<p>Triaud said the days wouldn\u2019t get much brighter than, say, a sunset on Earth. \u201cHowever, you will still feel quite warm, because you still receive just about as much energy from the star, which is in the infrared. That, you will feel with your skin,\u201d he said.<\/p>\n<p>It sounded as if Triaud was getting a warm glow just thinking about the scene.<\/p>\n<p>\u201cThe spectacle would be beautiful,\u201d he&nbsp;said, \u201cbecause every now and then you would see another planet, maybe about twice as big as the moon in the sky, depending on which planet you are on.\u201d<\/p>\n<p><em>In addition to the TRAPPIST-South telescope in Chile, instruments&nbsp;contributing to the observations included TRAPPIST-North in Morocco, HAWK-I on the European Southern Observatory\u2019s Very Large Telescope, UKIRT in Hawaii, the Liverpool and William Herschel telescopes in the Canary Islands, the SAAO telescope in South Africa and NASA\u2019s Spitzer Space Telescope.<\/em><\/p>\n<p><em>The Nature paper, \u201cSeven Temperate Terrestrial Planets Around the Nearby Ultracool Dwarf Star TRAPPIST-1,\u201d lists 30 authors including Gillon and Triaud.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A diagram shows seven exoplanets orbiting&nbsp;an ultracool dwarf star known as TRAPPIST-1. If the planets were transported to our own solar system, they\u2019d all lie within Mercury\u2019s orbit. (ESO Illustration) A second look at an exoplanet system 40 light-years from Earth has brought a bonanza for astronomers: not two, not three, but seven alien worlds [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[1874,559,4709,3403],"class_list":["post-19064","post","type-post","status-publish","format-standard","hentry","category-news","tag-astrobiology","tag-exoplanets","tag-planets","tag-trappist-1"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/19064"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=19064"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/19064\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=19064"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=19064"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=19064"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}