Changing Planet

New-found Earth-size Exoplanet Doomed

Artist’s impression of the planet Kepler-78b and its host star. Art by Karen Teramura (UHIfA)

Astronomers announced this week that they have spotted a rocky Earth-size planet beyond our solar system, the smallest alien world accurately sized by observers to date. However, the super-hot planet is no second Earth, and according to theories, the distant world some 700 light-years away from Earth shouldn’t exist.

The planet, Kepler-78b, was first discovered by its namesake NASA space telescope. The planet is about 20 percent larger than the Earth, with a diameter of 9,200 miles, and it weighs almost twice as much.

Using the world’s largest ground-based telescopes, two independent research teams have now confirmed the planet’s mass and density by measuring “wobbles” of its sun-like host star, seen as the exoplanet orbits around it. They report the confirmations in the journal Nature.

Unfortunately, Kepler-78b is not Earth 2.0, however, because it turns out that it circles its star at a scorching distance of one million miles. A year on this fast-paced little world lasts only 8.5 hours.

“It’s Earth-like in the sense that it’s about the same size and mass, but of course it’s extremely unlike the Earth in that it’s at least 2,000 degrees hotter,” says co-author Josh Winn, an astronomer at MIT.

“It’s a step along the way of studying truly Earth-like planets.”

The problem astronomers have with their finding is that according to what we understand about planet formation, this hot lava world couldn’t have formed so close to its star, nor could it have moved there.

“This planet is a complete mystery,” says study co-author David Latham, an astronomer at the Harvard-Smithsonian Center for Astrophysics. “We don’t know how it formed or how it got to where it is today. What we do know is that it’s not going to last forever.”

Astronomers have a quandary on their hands.  They don’t believe the planet could have formed in its current orbit because then Kepler-78b would have been inside the much larger, younger star. At the same time, it couldn’t have formed farther out and migrated inward, because it should have been drawn on a swirling kamikaze dive straight into the star.

“How it came to reside in its current 8.5-hour orbit is uncertain,” says planetary scientist Drake Deming of the University of Maryland in a commentary accompanying the studies. “Among the more exotic possibilities is that it is the remnant core of a disrupted gas giant,” he writes.

Because it has the tightest orbit around a star ever seen, one thing researchers know for sure is that Kepler-78b’s days are numbered. The extreme gravitational pull from its star will draw it ever closer in, ripping the entire planet apart in about three billion years.


Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.
  • kevin jones

    i had a dream about that and i ounce wrote a story about this…

  • Babu G. Ranganathan

    SCIENCE SHOWS THAT THE UNIVERSE CANNOT BE ETERNAL because it could not have sustained itself eternally due to the law of entropy (increasing energy decay, even in an open system). Einstein showed that space, matter, and time all are physical and all had a beginning. Space even produces particles because it’s actually something, not nothing. Even time had a beginning! Time is not eternal. Popular atheistic scientist Stephen Hawking admits that the universe came from nothing but he believes that nothing became something by a natural process yet to be discovered. That’s not rational thinking at all, and it also would be making the effect greater than its cause to say that nothing created something. The beginning had to be of supernatural origin because natural laws and processes do not have the ability to bring something into existence from nothing. What about the Higgs boson (the so-called “God Particle”)? The Higgs boson does not create mass from nothing, but rather it converts energy into mass. Einstein showed that all matter is some form of energy.

    The supernatural cannot be proved by science but science points to a supernatural intelligence and power for the origin and order of the universe. Where did God come from? Obviously, unlike the universe, God’s nature doesn’t require a beginning.

    EXPLAINING HOW AN AIRPLANE WORKS doesn’t mean no one made the airplane. Explaining how life or the universe works doesn’t mean there was no Maker behind them. Natural laws may explain how the order in the universe works and operates, but mere undirected natural laws cannot explain the origin of that order. Once you have a complete and living cell then the genetic code and biological machinery exist to direct the formation of more cells, but how could life or the cell have naturally originated when no directing code and mechanisms existed in nature? Read my Internet article: HOW FORENSIC SCIENCE REFUTES ATHEISM.

    WHAT IS SCIENCE? Science simply is knowledge based on observation. No one observed the universe coming by chance or by design, by creation or by evolution. These are positions of faith. The issue is which faith the scientific evidence best supports.

    Visit my newest Internet site: THE SCIENCE SUPPORTING CREATION

    Babu G. Ranganathan*
    (B.A. Bible/Biology)


    *I have given successful lectures (with question and answer period afterwards) defending creation before evolutionist science faculty and students at various colleges and universities. I’ve been privileged to be recognized in the 24th edition of Marquis “Who’s Who in The East” for my writings on religion and science.

  • Austin Daniel Strong

    Why does every site with a comment section have spam?

  • Paul

    Wow! You Christians are so funny! No wonder there is no hope for the future.

  • shitu musa

    only God know what he have “

  • gOddOg

    What kind of nonsense is this?!
    “God’s nature doesn’t require a beginning.”
    Says who & based on what, fantasy?!
    The age old question “who made god” is the easiest of all questions ever asked: HUMANS MADE GOD & not the other way around like in that ludicrous book called the Bible/Genesis!

  • larry lopez

    Why is it that every time there is a new scientific discovery a debate upon religion ensues?

    We are trying to understand how the universe works. For example we discovered microbes and as a result we discovered the cause of disease and alleviated much suffering. Ironically it turned out that disease was not a result of sin – a very popular religious belief.

    Now we are investigating and trying to understand planetary formation and how solar systems work. We can only do that by exploring other solar systems and gathering information. Will it lead to something useful. . .maybe, maybe not.

    But given the improvement in the human condition based upon the advances of science it is likely to have some benefit. And for those who wish to say that science has not improved our lives, I hope you stay true to your beliefs and. . .hey are you using a computer? you hypocrite!

    Now on to the fundamental problem with every religious posting . Planetary Science, Astrophysics, and Scientific inquiry are not all obsessed with cosmology. Cosmology is at its core a theoretical pursuit. No one is going to cook up a universe in their lab even if its a staggeringly big one like CERN.

    As our understanding of the universe grows it will alter refine and may even change the current theories of cosmology. Science is not an end it is a process. You can believe the current theory has merit, or you can disagree. Either way you are free to do so in Science. In fact you are encouraged to disagree. Science does not advance with everyone accepting the current theory as absolute truth.
    Religion however insists upon belief, and moreover insists it is right. As a result its believers have accepted it as truth and everything else is false.
    Whether an individual scientist is an atheist or a devout catholic monk who happens to discover genetics (Mendel) is not the point and fails to add to the discussion.
    The religious of every faith have their own theory of cosmology which often do not agree with each other for cultural reasons. Scientists have theories which do not agree for scientific reasons.
    And the ultimate truth is both groups may never KNOW but each feels that at present they are closer to the truth.

  • edias

    excellent blog by B.Ranganathan.

  • Alex

    There is no god

  • Eugenio

    “To the Universe, humans are bacteria with the ability to think. ”
    Eugenio Santillan

  • victor manuel cardenasmeza

    me gustan sus programas comentarios y concursos no obstante me guataria tener unas cuantas revistas de ustedes en erspañol a vuelta de colrfreo

  • Alin Ducharme

    God this, God that, Bla Bla Bla Bla……Who CARES……..!!!

  • jahmes

    “Oh my love, if you love me truly, await my kiss, in 3 billion years.” said ms. kepler 78b

  • Rigo Osano Relator

    It’s like Crematoria in Riddick movie ^^

  • Geraldo Severiano

    Eu sou um novo na fé crista e diante de tantos bilhoes em que se fala os nobres linkados eu nunca acreditei que doenças ou pobreza fosse castigo de Deus, tenho lido muitas noticias sobre descobertas planetarias e achados no espaço, mas enfim nada pode ser provado sao apenas teorias vazias e duvido que algum de nos viva ou veja qualquer uma delas ser comprovada eficasmente, se um objeto desta magnitude surge no universo onde dozem conhecer sem que eles tenham noçao de onde veio. acho que vou rever meus conceitos e aprofundar em minhas leituras biblicas porque creio sim que verdades sem medidas tenho tirado de la cada dia de minha vida, o homem esta muitos e muitos anos luz de descobrir algo consistente sobre o universo e que teorias nao provam nada, apenas suscitam contendas, e fazem c pessoas fracas em seu entendimento fiquem comentando assuntos que nem quem escreveu sabe ao certo o que esta falando.

  • Antonio Parker

    God is the ultimate scientist. Science doesn’t negate God or the universal consciousness. It almost affirms the idea of a supreme consciousness. There is a spiritual reality that are not governed by physical law. However, the universe as we know, seems to be govern by physical laws. Perhaps this is how God created it to be.

  • kabuto yakushi

    Christianity rules……………

  • Lost now found

    Dear Babu.,
    The reason why we creationists post our findings on these subjects is thus. We and you, were lied to about much of what you base these informative findings on. To be blunt…. Here are some reasons…. the history of the earth is taught to us as being billions of years old…. But nobody has yet to find a diamond in any of the twelve geological periods, that is absent of carbon 14 which is completely “dispensed” inside of 80 thousand years. Also no one has ever found coal in any of the geological periods absent of carbon 14 either. Also it doesnt take much image searching to see that fossils that modern scientists claim to be bilions of years old look no differant then todays living animals’ bone structures of the same genome. No evidence of evolving. Some argue that bacterial edaptions proves lifes ability to evolve, but no bacterial self-modification ever adds information which would be key if a speicies could become better adapted to its future, but modification only takes away information, or digresses. We have never found any fossels that have not had carbon 14 still in its make up.
    The bible states many scientific facts that have been found …..factual. Not all believers know all of the things they should, there is a lot of foolishness in the Christian group. Im not a christian but i know that science proves design if looked at unbiasedly.

  • cc

    this story would be a lot more interesting if kepler78b was expected to be ripped apart in…say…..3 years, rather than 3 billion years.

  • Patiscynical

    So all we really know now is that we don’t know everything.

  • miranda

    Perhaps as we peek into the distance we seeour future.

  • Roberto Salinas

    Traveling planet?

  • Abhishek

    While everyone should have the right to express his or her opinion, steps need to be taken to counter misguided fervour with which creationists like Ranganathan spread rumours and half baked lies. A lot of young people, laymen, fence sitters and even policy makers are followers of National Geographic, and if they see opinions stressing that every real fact which agrees with their view of religion is true and everything which does not is false, it will not bode well for humanity in the long run.

  • Sawlim yousuf

    Very interesting a quite fantastic.

  • Haftom

    God’s nature is infinite

  • Justin

    New astronomical discoveries give new opportunities to fine tune the astronomical models.

  • RC Montebon

    New home planet for new civilization of mankind



  • Kaiser Soze

    There are thousands of “Earths” out there:

    Can’t wait to visit them. Or at least my grandchildren.

  • niel

    According to John the Revelator, In the book of Revelation 21: 1 . And I saw new heaven and a new earth: for the first heaven and first earth will pass away; and there was no more sea. God Deity/ Existence.

  • Ace

    Gallifrey has been found.

  • Luka Žnidaršič

    Sometimes the comments are way beter than the article (although the article is very good) but the creatonist-science argue is just so funny to read.

    The argument is easy to finish: Religion is something beautiful if you want to belive it and it should be incouraged. But if you want the trouth, even if its harsh and may leave you feeling empty and unimportant, then science is the way to go.

    But whatever you do, don’t tell religious people that God doesent exist, and don’t tell science folk that God made the universe. Its just pointless and stupid, explain the article to yourselft as you wish, just be sure that you feel good about it.

  • Von Ace

    I’m 12 year old and interested to these things , please not to try fighting about religion vs. SCIENCE . Every people has their own beleifs let them beleive ehat they want. Im a religious person but at the same time i love science and new discoveries. I’m a filipino. Some here are muslims they have their own belief they even fight against goverment. So please dont make the fight be viral on internet

  • Jeremy Mair

    maybe this should make us realise what we have is precious.

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