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  • Hey there!

  • Welcome to Life Noggin.

  • You Earthlings are pretty attached to your sun, and for good reason.

  • It provides light and heat, drives photosynthesis that makes oxygen, and helps generate weather

  • patterns.

  • Without it, you wouldn’t exist.

  • But if the sun is so great, would it be better if there was more of it?

  • What if the sun has twice the mass it has now?

  • Too much of a good thing can be a bad thing, and in this case, it would so bad that no

  • one would survive.

  • But before I get to that, you have to understand why mass makes a difference.

  • As you probably know, the sun is a star, and stars come in a variety of masses.

  • Generally, a star with more massmore matter packed into itglows brighter and

  • hotter than one with less.

  • The smallest stars can be less than 8 percent the mass of the sun and give off only .01

  • percent as much energy.

  • The largest stars can be a hundred times more massive than the sun and emit thousands of

  • times as much energy.

  • Compared to these stars, the sun is actually a pretty normal mass.

  • But that doesn’t make its relationship to Earth any less special.

  • Many planets are either too close or too far away from their stars to support life.

  • Earth is in what we call the Goldilocks Zone, or the habitable zone, where it’s just far

  • enough away from the sun to have the right temperature for life to exist.

  • And were not the only planet like this.

  • Scientists believe there are billions of Earth-like planets in habitable zones across the Milky

  • Way!

  • In fact, in early 2017, NASA announced they’d found seven exoplanets 39 light years away

  • that might have water, and three of them are in their star’s habitable zone.

  • But all of them orbit their star closer than Mercury orbits the sun, sowhy don’t

  • they burn up?

  • Well, distance is only part of the equation.

  • These planets orbit an ultra-cool, very small dwarf star only 8 percent as massive as the

  • sun.

  • It’s also half as cold as the sun and less than one-thousandth as bright.

  • Being close to this star is the only way the planets could possibly capture enough light

  • and heat to support life.

  • If they were farther away, they would be too cold for life to exist.

  • So, back to your solar system.

  • If the sun were twice as massive as it is now, Earth would fall out of the habitable

  • zoneway out.

  • First off, with more mass, the sun’s luminositythe amount of energy and brightness it

  • gives offwould increase exponentially.

  • To see what might happen to you, let’s look at Sirius A, the brightest star in your sky.

  • It’s just about twice as massive as the sun but more than 20 times as luminous.

  • It’s also several thousand degrees hotterwell over 9000 degrees celsius, compared

  • to 5500 degrees for the sun.

  • If the sun was that massive and Earth kept the same distance from it, you’d be toast,

  • maybe literally.

  • Earth would not just get significantly hotter, but the oceans would boil away, leaving a

  • vapor cloud that would trap even more heat.

  • Plus, if the sun doubled in mass, its gravitational pull would increase.

  • This could change the Earth’s orbit and tidal patterns, possibly making tides stronger.

  • All of this would not be good for you Earthlings.

  • I think it’s probably better to appreciate the sun you have now.

  • Want to know what would happen if the Earth doubled in size?

  • Check out this video.

  • Do you think life exists on other planets in these habitable zones?

  • Let me know in the comment section below.

Hey there!

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B1 INT US sun habitable mass earth star habitable zone

What If The Sun Doubled In Mass?

  • 1977 43
    Steven Sou   posted on 2017/05/11
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