[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/5917\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003EAstronomers close in on far-away earth\u003C\/h2\u003E\u003Cp\u003EUsing an ultra-sensitive light-splitting spectrograph, EU-funded researchers have managed for the first time to identify a rocky, iron-rich planet billions of kilometres away \u2013 a critical step towards discovering a far-away earth.\u003C\/p\u003E\u003Cp\u003EThe new device, called HARPS-N, was made with nanoscale precision and operates in a vacuum at temperatures stable within a thousandth of a degree. Researchers at the EU-funded ETAEARTH project, coordinated by Dr Alessandro Sozzetti\u0026nbsp;at the Italian National Institute\u0026nbsp;for\u0026nbsp;Astrophysics (INAF),\u0026nbsp;trained it on Kepler-78, a star 400 light years away in the Cygnus constellation, in order to pick out the tiny fluctuations caused by the planet Kepler-78b.\u003C\/p\u003E\u003Cp\u003EKepler-78b was first spotted in 2013 by the Kepler spacecraft, which scans the night sky in search of planetary transits that periodically dim the luminosity of distant stars. The chances of a planet crossing its line of sight are two hundred to one, but Kepler has evened out the odds by tracking some 150 000 stars.\u003C\/p\u003E\u003Cp\u003EKepler-78b, a planet just 20 % larger than earth, orbits at the breakneck speed of three revolutions a day. It is this tight orbit that means it pulls its star just enough to allow researchers at the ETAEARTH project to identify its mass and density \u2013 elusive properties for extra-solar earth-sized planets and key clues as to their composition.\u003C\/p\u003E\u003Cp\u003EAstronomers determine the mass of distant planets by investigating how their gravitational pull makes their parent star wobble.\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003E\u2018It may take another ten years to spot a planet with conditions like earth, and maybe centuries to reach it.\u2019\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EDr Emilio Molinari, the director of the TNG telescope at INAF \u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003E\u2018When a star wobbles away from observers on earth, its colour reddens a little. When it wobbles towards us, it shifts towards the blue,\u2019 said Dr Lars Buchhave, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Massachusetts, US, who helped calculate the mass of Kepler-78b. \u2018This is the same phenomenon which alters the pitch of a passing police siren.\u2019\u003C\/p\u003E\u003Cp\u003EThis phenomenon, called the Doppler effect, is used to measure things like the speed of an object with radar and as a tool in medical imaging. However, it has also has revealed the existence of hundreds of Jupiter-like gas giants beyond the confines of our solar system since the discovery of the first planet outside our solar system in 1995.\u003C\/p\u003E\u003Cp\u003E\u2018Still, the wobble produced by Kepler-78b remains ten times smaller than that of Jupiter on the sun,\u2019 said Dr Emilio Molinari, the director of the TNG telescope at INAF in the Canary Islands.\u003C\/p\u003E\u003Cp\u003EThe HARPS-N spectrograph was mounted on the 3.6 metre wide TNG telescope and pointed at Kepler-78 for 80 nights. \u2018It was very challenging to achieve such high accuracy, but in the end we got it. We now know that Kepler-78b is just 60 % more massive than earth.\u2019\u003C\/p\u003E\u003Cp\u003EThe Doppler wobble of Kepler-78b\u2019s parent star reveals that the planet\u2019s density is the same as that of earth, suggesting that it is also composed of rock and iron. However, whether we would want to visit this new world is another matter. The proximity of Kepler-78b to its parent star leads to temperatures so high as to melt the rock on its surface and strip away its atmosphere.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ETen years\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe results obtained are of philosophical as well as scientific interest. Theorists are still trying to understand how Kepler-78b landed in such a tight orbit. But the fact that the planet exists at all indicates that, from an astronomical perspective, the earth is not unique.\u003C\/p\u003E\u003Cp\u003E\u003Cspan class=\u0022img_legend\u0022 style=\u0022float: left;\u0022\u003E\u003Cfigure role=\u0022group\u0022\u003E\n\u003Cimg alt=\u0022The ultra-sensitive HARPS-N spectrograph. Copyright: \u00a9 UNIGE\u0022 height=\u0022200\u0022 src=\u0022\/research-and-innovation\/sites\/default\/files\/hm\/HARPs%20instrument.jpg\u0022 title=\u0022The ultra-sensitive HARPS-N spectrograph. Copyright: \u00a9 UNIGE\u0022 width=\u0022267\u0022\u003E\n\u003Cfigcaption class=\u0022tw-italic tw-mb-4\u0022\u003EThe ultra-sensitive HARPS-N spectrograph. Copyright: \u00a9 UNIGE\u003C\/figcaption\u003E\n\u003C\/figure\u003E\n\u003Cem\u003EThe ultra-sensitive HARPS-N spectrograph. Copyright: \u00a9 UNIGE\u003C\/em\u003E\u003C\/span\u003EFor a planet to harbour life, scientists believe it must sit in the habitable zone \u2013 a precise distance from a star where the temperature is just right for water to be liquid. That means its Doppler wobble will be much fainter than that caused by the tight orbit of Kepler-78b.\u003C\/p\u003E\u003Cp\u003EThe biggest problem that planet-hunters face in detecting this wobble is stripping out effects of activity on the surface of the star.\u0026nbsp;\u2018If we can crack this problem, we will be in a much better position to detect earth-mass planets orbiting in the habitable zones of solar-type stars,\u2019 said Professor Andrew Cameron, who heads the School of Physics and Astronomy at the University of Saint Andrews in the UK.\u003C\/p\u003E\u003Cp\u003EThey reckon that the best chance of spotting an earth-like planet is to focus on small stars called red dwarfs, where the habitable zone is closer to the star, increasing the Doppler wobble.\u0026nbsp;\u2018It may take another ten years to spot a planet with conditions like earth, and maybe centuries to reach it,\u2019 said Dr Molinari at INAF. \u2018But even if we just see the first steps of this great journey, someone has to start it.\u2019\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-f2dj2zypbnlnzucfph8t8g9hzkwn1su3ftzr8ikvsl4\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-f2Dj2zYpBnLnZuCFph8T8G9hZKwn1su3ftZr8IKVSl4\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]