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Scientists confirm first exoplanet candidate found by Kepler

Worlds without end: Ten years after Kepler was launched into space to find exoplanets, astronomers have finally confirmed one of the space telescopes thousands of candidates.

Despite being the very first planet candidate discovered by NASA’s Kepler Space Telescope, the object now known as Kepler-1658 b had a rocky road to confirmation. The initial estimate of the size of the planet’s host star was incorrect, so the sizes of both the star and Kepler-1658 b were vastly underestimated. It was later set aside as a false positive when the numbers didn’t quite make sense for the effects seen on its star for a body of that size. Fortuitously, Chontos’ first year graduate research project, which focused on re-analyzing Kepler host stars, happened at just the right time.

“Our new analysis, which uses stellar sound waves observed in the Kepler data to characterize the host star, demonstrated that the star is in fact three times larger than previously thought. This in turn means that the planet is three times larger, revealing that Kepler-1658 b is actually a hot Jupiter-like planet,” said Chontos. With this refined analysis, everything pointed to the object truly being a planet, but confirmation from new observations was still needed.

“We alerted Dave Latham (a senior astronomer at the Smithsonian Astrophysical Observatory, and co-author on the paper) and his team collected the necessary spectroscopic data to unambiguously show that Kepler-1658 b is a planet,” said Dan Huber, co-author and astronomer at the University of Hawaiʻi. “As one of the pioneers of exoplanet science and a key figure behind the Kepler mission, it was particularly fitting to have Dave be part of this confirmation.”

It is important to remember that until scientists obtain independent data on each of these candidates, they are not yet confirmed as exoplanets, and might only be false positives. To do this, however, is going to take a lot of work and time.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

 
Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.

7 comments

  • Col Beausabre

    “Hot Jupiter” – How long would that continue ? Wouldn’t the atmosphere of such a planet be boiling away ? Does that imply that planet was (much ?) more massive at one time? Enquiring minds want to know !

  • Edward

    Col Beausabre asked: “Wouldn’t the atmosphere of such a planet be boiling away ?

    Maybe, but not necessarily. The gravity may make the escape velocity so large that not many atmosphere molecules can reach that speed, even though the planet’s atmosphere is hot.

  • wayne

    Col / Edward–
    extremely interesting stuff!

    What do we mean by “hot?” What is the escape-velocity of our own Jupiter?

  • Dick Eagleson

    Not sure just how hot “hot Jupiters” are.

    Jupiter’s escape velocity is 59.5 km./sec. That’s about 5.3 times Earth’s escape velocity of 11.2 km./sec.

  • wayne

    Dick–
    Thank you.

    What’s the limit for the escape velocity produced by our chemical rockets?

  • Edward

    wayne,
    You asked: “What’s the limit for the escape velocity produced by our chemical rockets?

    This is a tricky question to answer. It largely depends upon the rocket design and the rocket equation.
    https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

    The rocket equation shows that the limit depends upon the exit velocity of the exhaust propellant and the ratio of the mass of the rocket before the burn to the mass of the rocket at the end of the burn, the assumption being that the difference in mass is entirely propellant, as opposed to dropped stages, fairings, escape towers, batteries (a la Electron rocket), etc.

    As can be seen by the equation, the rocket efficiency (Isp, specific impulse) is important to the final velocity, and that is dependent upon things such as the propellant used, engine type, and engine design.

    Generally, the lighter the propellant, the higher the efficiency. Hydrogen atoms would be more efficient than water molecules, which would be more efficient than a combination of water and carbon dioxide. However, the propulsive force generated by the lighter propellant would be less than for the heavier one, so a first stage launching from the Earth may use kerosene and oxygen rather than hydrogen and oxygen in order to generate the force needed to get off the surface, even though the efficiency is lower. Saturn V first stage only had an Isp of 255 seconds but a thrust almost 8 million pounds.

    Chemical engines tend to get lower Isp than ion engines, which need an external power source. Chemical engines generally use the reaction of two chemicals to generate the energy needed to accelerate the exhaust propellant.

    For chemical engines, the combustion chamber design can determine such things as whether the combustion is complete or incomplete, helping to determine the weight of the exhaust propellant. The bell shape is important, as the ratio of the exit to the throat wants to be larger for a vacuum engine than for a sea level engine.

    For ion engines, the power source is important, because the power required to accelerate the propellant is dependent upon the square of the exit velocity. To double the exit velocity requires four times as much power, or four times the mass of the solar arrays, batteries, or nuclear/chemical power plant. And that drives the all important ratio of the beginning to ending mass of the vehicle.

  • wayne

    Edward–
    Thank you.

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