Monday , September 20 2021

The ancient "ultra-terrestrial" exoplanet discovered around the nearby star

The closest star to the sun hosts a large frozen planet.

Astronomers have found strong evidence for a cold foreign world about 3.2 times as massive as the Earth that surrounds Star Barnard, a dim red dwarf that is only 6 light years away from the sun. Star Barnard is our closest neighbor, except for the three-star Alpha Centauri system, which is about 4.3 light years away.

The recently-discovered world, known as Barnard's Star, remains a candidate for the planet now. But the researchers who saw it are certain that the alien planet will eventually be confirmed. [Barnard’s Star b: What We Know About the “Super-Earth’ Candidate]

"After a very careful analysis, we are 99% sure that the planet is there," Ignasi Ribas, of the Catalonia Institute of Space Studies and Space Science Institute in Spain said in a statement.

"However, we will continue to observe this fast star in order to rule out the possible but unlikely natural variations of the stellar brightness that could be transformed into a planet," added Ribas, the lead author of a new study announcing Barnard's detection. ; s Star b. This study was published online today (November 14th) in the journal Nature.

The impression of an artist on the new

Barnard's Star b, if confirmed, will not be the closest exoplanet on Earth. This characterization is held by the Proxima b-sized world of earth, revolving around Proxima Centauri, one of Alpha Centauri's trio.

NASA's Kepler Space Telescope has shown that small planets are common to our Milky Way galaxy in general. Together, Proxima b and Star Barnard b strongly support that such worlds are "also common in our neighborhood," co-author Johanna Teske of the Earth Magnetism Department at the Carnegie Science Institute in Washington . . "And that's very exciting."

A nearly solar neighbor

The Star of Barnard was named by the American astronomer E.E. Barnard, who in 1916 discovered the speed reported by Ribas. No other star moves faster than Earth's sky from Star Barnard, which travels about the width of the full moon every 180 years. [Gallery: The Strangest Alien Planets]

This incomparable phenomenal motion is a consequence of Star Barnard's proximity and high (but not record) speed of 500,000 km / h in relation to the sun.

RELATIVE: 2018 Site space:


2018 Space Calendar

See the collection

1st January 2: Supermoon / Full Wolf Moon

The moon will make its closest approach to Earth on New Year's Day and will appear larger and brighter than usual, winning the "Supermoon" distinction.

In addition, the first full moon of any year wins the "Full Wolf Moon" award. The term was created by local Americans as a nod for cries of wolves often heard outside their villages in January.

Photo: Matt Cardy / Getty Images

3 January 4: Quadruple Meteor Shower

The Quadrantid meteor shower, which is known to produce 50-100 meteors at its peak, is the first large 2018 shower.

Unfortunately, light from almost full moon will exclude most of the show.

Photo: NurPhoto / NurPhoto via Getty Images

January 31: Total Lunar Eclipse / Blue Moon

A blue moon is the term for the second full moon in a month with more than one full moon.

The January Blue Moon also happens to coincide with a total lunar eclipse.

Photo: REUTERS / Mike Hutchings

February 15: Partial solar eclipse

This type of solar eclipse occurs when the moon casts a shadow covering only part of the Sun.

The partial solar eclipse on February 15 will be visible only in parts of South America and Antarctica. Those wishing to take it should wear special protective glasses.

Photo: REUTERS / Tatyana Makeyeva TPX IMAGES OF THE DAY

March 2: Full Moon

Another term devised by Native Americans, the "Full Moon Worm" is the distinction that was made in the first full moon in March.

As the temperature gets warm, the soil begins to soften and earthworms begin to lie down their heads again in the soil.

Photo by NICHOLAS KAMM / AFP / Getty Images

March 15: Mercury reaches the largest East elongation

Mercury will reach its largest eastern elongation from the sun (ie its highest point above the horizon) on March 15th.

This will make the planet more visible than usual.

Photo: The Royal Observatory of Greenwich, London

22 April 23: Lyrid Meteor Shower

The Lyrid meteor shower, which usually produces about 20 moons per hour, will arrive in the afternoon between the night of April 22 and the morning of the 23rd.

Photo: Ye Aung Thu / AFP / Getty Images

April 30: Full pink moon

"Full Pink Moon" is another term believed to have been created by American breeds.

In April, the weather finally begins to warm and the flowers begin to appear, winning the full moon of the month its beautiful name.

Photo: Ben Birchall / PA Images via Getty Images

6 May 7: Eta Aquarid Meteor Shower

The Eta Aquarids meteor atmosphere, made up of dust particles left behind Halley's Comet, can produce up to 60 times per hour at its peak.

Although most of its activity can be observed in the southern hemisphere, the northern can still take part in the demonstration if the weather conditions allow.

Photo: NASA

May 9: Zeus reaches the Opposition

The gas giant will make its closest approach to Earth on May 9, making it brighter than any other season of the year.

Photo: Catholic history archive through Getty Images

May 29: Full Moon

In May full moon was given this name by the American tribes, as the beginning of the month is usually when the flowers are in full bloom.

Photo: REUTERS / Navesh Chitrakar TPX IMAGES OF THE DAY

June 27: Cronus is opposed

Saturn will make its closest approach to the Earth on June 27, making it brighter than any other time of the year.

Photo: NASA / JPL-Caltech / Institute of Space Science / Manual through REUTERS

June 28: Full Moon Moon

As the last full moon of spring, the stars can expect this to be large and bright – but unlike his name, it is not red.

The strawberry season reaches its climax in June, winning the first full moon of the month its wonderful name.

Photo: Matt Cardy / Getty Images

July 13: Partial solar eclipse

This type of solar eclipse occurs when the Moon shifts a shadow that covers only part of the Sun.

The partial solar eclipse on July 13 will be visible only in parts of South Australia and Antarctica. Those wishing to take it should wear special protective glasses.


July 27: Mars reaches the opposition

You guessed it – Mars will make its closest approach to Earth on July 27, making it brighter and therefore more visible than any other time of year.

Photo: NASA / Handout via Reuters

July 27: Full Moon

The full moon of July was named "Full Buck Moon" by American breeds, as it appears during this time of year when male deer are starting to grow their new horns.

Photo: REUTERS / Carlo Allegri

28 July 29: Lunar eclipse total

A total lunar eclipse occurs when the moon passes completely through the shadow of the Earth, giving the moon a dark-reddish appearance.

The lunar eclipse of July will be visible in North America, East Asia and Australia.

Photo: REUTERS / Kacper Pempel

August 11: Partial solar eclipse

This type of solar eclipse occurs when the moon casts a shadow covering only part of the Sun.

The partial solar eclipse on 11 August will only be visible in parts of Canada, Greenland, northern Europe and northern and eastern Asia. Those wishing to take it should wear special protective glasses.


12 August 13: Persistent meteor shower

The atmosphere of Perseids, consisting of dust particles left behind by Swift-Tuttle Comet, can produce up to 60 times per hour at its peak.

The thin crescent on the evening of August 12 will create favorable viewing conditions for the celestial spectacle, which should be visible all over the world.

Photograph: REUTERS / Paul Hanna

17 August: Venus reaches the largest East Elongation

Venus will make its closest approach to Earth on August 17, making it brighter and therefore more visible than any other time of year.

Photo: Photo12 / UIG via Getty Images

August 26: Full Moon

The full moon of August gained this distinction from the tribes of indigenous Americans, as sturgeon was caught more easily during this month.

Photo: Pradita Utana / NurPhoto via Getty Images

Sept. 7: Posidos reaches the opposition

Poseidos will make its closest approach to Earth on Sept. 7, making it brighter and therefore more visible than any other time of year.

However, due to the distance from Earth, the blue planet will only appear as a small dot for even those using telescopes.

Photo: Imagery of the season / NASA / The LIFE / Getty Images Collection)

24 September 25: Full Moon

The name & # 39; Harvest Moon & # 39; goes to the full moon that happens closer to the summer equinox each year.

Photo: Santiago Vidal / LatinContent / Getty Images

October 8: Draconid Meteor Shower

The Draconid meteor shower, which consists of dust particles left behind the 21P Giacobini-Zinner comet, produces only 10 moons per hour at its peak.

However, the new moon on the night of October 9 will create extremely favorable viewing conditions for the shower, which should be visible all over the world.

Photo: NASA

21 October 22: Orionid Meteor Shower

Another shower produced by Comet Halley, the Orionids will be blocked at least in part by the light of almost full moon on October 21st.

Photograph: Yuri Smityuk TASS via Getty Images

October 23: The sky reaches the opposition

The sky will make its closest approach to Earth on October 23, making it brighter and therefore more visible than any other time of year.

Unfortunately, it is so far from Earth that it will not be visible without a powerful telescope.

Photo: Jet Protection Lab / NASA / LIFE / Getty Images Collection

October 24: Full Moon

The Full Moon of October was named "Full Moon Moon" by US American breeds, since animals are more easily identified during this year after the loss of plants /

Photo: PA Wire / PA images

5 November 6: Taurids Meteor Shower

Taurids is a small meteor rock that produces only 5-10 meteorites per hour at its peak.

Photo: NASA

17 November 18: Leonid Meteor Shower

The Leonid meteor shower, which radiates from the constellation Leo, produces about 15 moons an hour at its peak.

Photo: Ali Jarekji / Reuters

November 23: Full Moon Moon

The full moon in November was named after the Native America breeds, which would create beaver traps during the month in the hope of catching the creatures for their warm fur.

Photo: Matt Cardy / Getty Images

13 December 14: Geminids Meteor Shower

The shower of Geminids meteors, produced by the debris left behind by an asteroid known as 3200 Phaethon, is known as one of the most impressive of its kind.

The demonstration can produce up to 120 hours per hour at its peak and will be visible across the globe on the night of December 13th.

Photo: REUTERS / Navesh Chitrakar

21 December 22: Ursids Meteor Shower

The Draconid meteor shower, which consists of dust particles that remain behind Tuttle Comet, produces about 10 times per hour at its peak.

Unfortunately, the full moon on December 22 will probably create unfavorable viewing conditions for the smallest show.

Photo: REUTERS / Daniel Aguilar DA / LA

December 22: Full cold moon

It is not surprising that the full moon of December was named after the American tribes after the cold, in the winter.

Photo: Matt Cardy / Getty Images



And the star of Barnard is approaching daily: In about 10,000 years, the red dwarf will take over the mantle of the closest star from the Alpha Centauri system. At that time, only 3.8 light years will separate the star of Barnard from the sun.

The Star of Barnard is about twice as old as Earth's sun, one sixth as huge and just 3 percent bright. Because the Barnard star is so dim, its "habitable zone" – the range of distances where wet water may be on the surface of the world – is very close. In fact, the researchers estimate that the band will be a band that is 0.06 AU to 0.10 AU from the star. (An AU unit, or an astronomical unit, is the distance between Earth and the sun – about 93 million miles or 150 million kilometers.)

The concept of habitable zone is of course difficult. Measuring the real home of the world requires strong working knowledge of atmospheric composition and its thickness, among other features. And this information is hard to find for the exoplanets.

A long search

Star Barnard has long been the target of the exoplanet hunters, but their searches have always been empty – so far.

And the new detection was not easy: Ribas and his team analyzed vast amounts of data, both archival and recent, before finally digging Barnard's star.

They used the "radial velocity" method, which searches for changes in the stellar light caused by the gravitational towering of a planet in orbit. Such tugs cause a star to swing slightly, changing the light to red wavelengths at times and towards the blue end of the spectrum to others, as seen from Earth. [7 Ways to Discovery Alien Planets]

"We have used observations from seven different instruments, covering 20 years of measurement, making it one of the largest and most extensive sets of data ever used for accurate radial speed studies," said Ribas in the same statement. "The combination of all data led to a total of 771 measurements – a huge amount of information!"

Never before had the radial velocity method been used to find such a small planet at such a distant track, members of the study group said. (Big, almost planets drag the host stars louder and thus cause more dramatic and more easily detectable, light shifts.)

These seven instruments were HARPS at the La Silla Observatory of the European Observatory of the South (ESO) in Chile. the ultraviolet and optical pixel spectrometer in the very large telescope at ESO's Paranal Observatory in Chile. HARPS-North, at Galileo National Telescope in the Canary Islands. the Echelle high-resolution spectrometer on the 10-meter Keck telescope in Hawaii. the Spectrograph of the Carnegie Institute's Planet Finder Spectrograph at the 6.5-meter Magellan Telescope at the Las Campanas Observatory in Chile. the planetary automatic locator on the 2.4 meter telescope at the Observatory Lick of the University of California. and & CARMENES, at the Observatory of Calar Alto, Spain.

Researchers also detected hints of another potential planet in the system, wandering farther from Barnard's Star, northern, with an orbital period of 6,600 days of Earth. But this second message is too weak to be considered a candidate planet, Teske said.

"There is not enough data," he told

A cool super land

Barnard's star is at least 3.2 times more massive than our own planet, making it a "super-earth" – the class of worlds that are significantly larger than the Earth, but smaller than the "ice giants" like Neptune and Uranus.

The new contender planet is at 0.4 AU from its star and hosts a track every 233 days of the Earth, according to the new study.

This orbital distance is similar to that of irradiated mercury in our solar system. But because Barnard's Star is so weak, the potential planet is just around the snow line of the system – the area where volatile materials, like water, can be condensed into solid ice creams.

"So far, only giant planets have been located at such a distance from their stars," said Rodrigo Diaz, of the Institute of Astronomy and Physics at the National Scientific and Technical Research Council and the University of Buenos Aires in Argentina. ένα συνοδευτικό άρθρο "News and Views" που δημοσιεύθηκε επίσης σήμερα στο Nature.

"Η ανακάλυψη από τους συγγραφείς ενός πλανήτη χαμηλής μάζας κοντά στη γραμμή χιονιού θέτει ισχυρούς περιορισμούς στα μοντέλα σχηματισμού αυτού του τύπου πλανήτη", πρόσθεσε ο Diaz, ο οποίος δεν συμμετείχε στη νέα μελέτη.

Το Αστέρι του Μπάρναρντ, αν πράγματι υπάρχει, δεν είναι μια πολλά υποσχόμενη κατοικία για τη ζωή όπως την ξέρουμε, τουλάχιστον όχι στην επιφάνεια. Ο δυνητικός πλανήτης είναι πιθανότατα πολύ κρύος, με εκτιμώμενη θερμοκρασία επιφάνειας περίπου 275 βαθμών Φαρενάιτ (μείον 170 βαθμούς Φαρενάιτ), ανέφεραν μέλη της ομάδας μελέτης.

Η επιβεβαίωση του Star Barnard είναι απίθανο να προέρχεται από επιπρόσθετες μετρήσεις ακτινικής ταχύτητας, γράφει ο Diaz. Αλλά οι υπερ-ακριβείς μετρήσεις των θέσεων των αστεριών, όπως αυτές που έχουν γίνει τώρα από το διαστημικό σκάφος Gaia της Ευρωπαϊκής Διαστημικής Υπηρεσίας, μπορούν να κάνουν τη δουλειά τα επόμενα χρόνια, πρόσθεσε.

"Ακόμη πιο συναρπαστικά, η επόμενη γενιά επίγειων οργάνων, που θα τεθεί σε λειτουργία και το 2020, θα πρέπει να είναι σε θέση να απεικονίσει άμεσα τον αναφερόμενο πλανήτη και να μετρήσει το φάσμα του φωτός", γράφει ο Diaz.

«Χρησιμοποιώντας αυτό το φάσμα, τα χαρακτηριστικά της ατμόσφαιρας του πλανήτη – όπως οι άνεμοι και ο ρυθμός περιστροφής του – θα μπορούσαν να συναχθούν», πρόσθεσε. «Αυτός ο αξιοθαύμαστος πλανήτης μας δίνει ένα βασικό κομμάτι στο γρίφο του πλανητικού σχηματισμού και εξέλιξης και μπορεί να είναι από τους πρώτους εξωπλανήτες χαμηλής μάζας των οποίων οι ατμόσφαιρες εξετάζονται λεπτομερώς».



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