Massive COCONUTS Exoplanet Discovery: Giant Planet Just 35 Light Years From Earth

Illustration of gas-giant planet COCONUTS-2b. Credit: B. Bays (SOEST/UH)

Astronomers have discovered thousands of exoplanets — planets beyond our solar system — but few have been directly imaged, because they are extremely difficult to see with existing telescopes. A University of Hawaiʻi Institute for Astronomy (IfA) graduate student has beaten the odds and discovered a directly imaged exoplanet, and it’s the closest one to Earth ever found, at a distance of only 35 light years.

During the pandemic, Zhang met with fellow researchers on Zoom to discuss the discovery

Using the COol Companions ON Ultrawide orbiTS (COCONUTS) survey, IfA graduate student Zhoujian Zhang and a team of astronomers, Michael Liu and Zach Claytor (IfA), William Best (University of Texas at Austin), Trent Dupuy (University of Edinburgh) and Robert Siverd (Gemini Observatory/National Optical-Infrared Astronomy Research Laboratory) identified a planet about six times the mass of Jupiter. The team’s research, published in The Astrophysical Journal Letters, led to the discovery of the low-temperature gas-giant planet orbiting a low-mass red dwarf star, about 6,000 times farther than the Earth orbits the Sun. They dubbed the new planetary system COCONUTS-2, and the new planet COCONUTS-2b.

The exoplanet is about six times the mass of planet Jupiter.

“With a massive planet on a super-wide-separation orbit, and with a very cool central star, COCONUTS-2 represents a very different planetary system than our own solar system,” Zhang explained. The COCONUTS survey has been the focus of his recently-completed PhD thesis, aiming to find wide-separation companions around stars of all different types close to Earth.

IfA graduate student Zhoujian Zhang

Trapped heat helps detect planet

COCONUTS-2b is the second-coldest imaged exoplanet found to date, with a temperature of just 320 degrees Fahrenheit, which is slightly cooler than most ovens use to bake cookies. The planet can be directly imaged thanks to emitted light produced by residual heat trapped since the planet’s formation. Still, the energy output of the planet is more than a million times weaker than the Sun’s, so the planet can only be detected using lower-energy infrared light.

“Directly detecting and studying the light from gas-giant planets around other stars is ordinarily very difficult, since the planets we find usually have small-separation orbits and thus are buried in the glare of their host star’s light,” said Liu, Zhang’s thesis advisor. “With its huge orbital separation, COCONUTS-2b will be a great laboratory for studying the atmosphere and composition of a young gas-giant planet.”

The planet was first detected in 2011 by the Wide-field Infrared Survey Explorer satellite, but it was believed to be a free-floating object, not orbiting a star. Zhang and his collaborators discovered that it is in fact gravitationally bound to a low-mass star, COCONUTS-2A, which is about one-third the mass of the Sun, and about 10 times younger.

IfA astronomer Michael Liu

Darkness prevails

Due to its wide-separation orbit and cool host star, COCONUTS-2b’s skies would look dramatically different to an observer there compared to the skies on Earth. Nighttime and daytime would look basically the same, with the host star appearing as a bright red star in the dark sky.

Zhang’s discovery has fueled his desire to continue to explore exoplanets, brown dwarfs, and stars. The aspiring astronomer graduated from IfA this summer and will begin his postdoctoral research in fall 2021, with IfA alumnus Brendan Bowler, an astronomy professor at the University of Texas at Austin.

Reference: “The Second Discovery from the COCONUTS Program: A Cold Wide-orbit Exoplanet around a Young Field M Dwarf at 10.9 pc” by Zhoujian Zhang, Michael C. Liu, Zachary R. Claytor, William M. J. Best, Trent J. Dupuy and Robert J. Siverd, 28 July 2021, The Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ac1123

AstronomyExoplanetPlanetsPopularUniversity of Hawaii at Manoa
Comments ( 24 )
Add Comment
  • Kathleen Moohan

    Thanks

  • Walter Schmuch

    Will Musk or Bezos be the first people to sunbathe on Coconuts 2?

  • brian

    Good

  • Jack Sparrow

    Sounds like a binary star system to me

  • John Bayer

    “You’re using COCONUTS!” (h/t Monty Python)

  • Nadarajan Mariapp

    To all aspiring Astrononers visit seriously India’s Tamil Nad Temples from Rameshwaram Temple up to Northern India’s Lord Shiva’s
    Temples built,between one Thousand
    to Two Thousand yrs.BC.for the secrets to know and understand about Exoplanets,Parallel Universes etc.found within the Physical Universe!
    Remember the vastness of these Universes showing these secrets
    I cannot REVEAL to Earth Scientists .
    Find out these amazing Truths yourselves from all Lord Shiva’s Temples inside and outside .
    No pains! No Gains!
    My clue to all.
    “How I wish I could recollect of
    Circular round the exact relationship Archimedes Unwound”
    gives the approx.value of Pi.
    Can you find thd exact Value of Pi
    Revealed among Lord Shiva’s Magnificient colorful Temples ;
    all built on a Straight line (refer India’s Temples map of Lord Shiva ).
    GOOD LUCK.Listening is the Wealth of all Wealth.
    Thirukural.

    MAY THE BLESSINGS BE

    • Torbjörn Larsson

      Hard to tell is that was superstition or joking, but in any case it isn’t fact.

  • Monique Chouinard

    @Walter Schmuck
    I hope it’s elon musk
    He wants to try to send people to Mars regardless if it’s a one way trip lol

  • John C Morgan

    Great job! How incredible! Wish I were you. Enjoy your success.

  • Monte

    Where is it? Where’s the picture of it? If you can see it then show it to me. Who falls for this crap 🤣

    • Torbjörn Larsson

      Because it isn’t crap.

      You can read, I assume? Read the paper and find the images for yourself.

  • Robert grims

    1 light year is over 6 trillion miles. Our next closest star is 4 light years and takes 76,000 years to reach at current speeds. So, 35 light years is not near. This space (boy, we are snooo close) crap, is done to raise money.

    • Torbjörn Larsson

      Maybe you should read more on the subject – the nearest star is just 1/10 the distance.

      That planet is near in terms of space and – more importantly – in terms of capabilities of the current and near future telescopes.

  • Prashanth

    Cool. So near. When is the next bus to this coconut planet by the way??

  • Shaikh Naeem

    All that perished is not God. But time to time only messengers are sent on earth with special power at that time. They all perished and transferred in heavens. We all will perish except one who created everything.After doomsday only humans will be regenrated for calculation of wordly life and will be send to heaven or hell as per belief,and deeds

    • Torbjörn Larsson

      Superstition.

  • Bob

    Of one wants to explore brown dwarfs & planets planet x is only 83 million miles away. Why go 35 trillion miles away?

    • Torbjörn Larsson

      Yes, scientists doesn’t want to go there for sure. They want to study it.

      But many others starts to speculate in things we don’t have the capability for. Dunno why they do that since it is completely uninteresting.

      • Gato Negro

        Mr. Larson, you obviously have an interesting mind and are curious about the world and universe around you, it is pointless to try and talk sense to the people that troll the internet. These guys say that these discoveries are useless yet you find them reading them, they clearly just want to post ridiculous comments and insults. These will one day become ashes and dirt and the Universe will continue on in all its fascinating glory. Stay curious.

  • Jakes

    So what? They saw some glimmer and assumed based on outdated theories that it must be a planet. We have so much more to explorer on our own planet. How can someone celebrate mediocrity like claiming they discovered some distant radiation and how will that help humanity
    Such a waste of time and talent.

  • muihik

    how are you

  • Charan

    I feel that all planets are a combination turning giant somewhere in the universe or other planet. The death of this big giant became slowly as planets and slowly from that human race is evolved.

  • Marc Jennings

    I’d be more interested in getting to Proxima B at 1.4 parcec…

  • JD

    The nearest exoplanet known is proxima centauri b, which 4.25 light years away, not this object.