Archive for February 2020

What if Earth Had a Growth Spurt!   Leave a comment

“Super-Earth’s” are faraway planets are about the size of Earth (between 2 and 10 times larger), belong to other solar systems and reside close to their own stars. These super earths are rocky worlds, smaller than gas giants like Neptune and Uranus, and sporting relatively thin atmospheres. NASA’s Kepler spacecraft, over a 4 year period discovered numerous examples of these super Earth’s.

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So, what on earth would happen if Earth had a sudden growth spurt and became a super-Earth? how would our suddenly giant super-size Earth affect its inhabitants? Everything including humans would be little short, squat versions of their/our current selves! If planetary size increases but everything on the planet remains the same gravity increases proportionally. So, if Earth suddenly doubled in size humans would immediately double their weight due to the pull of gravity on us also doubling.

 

 

 

 

 

 

 

There would be far too much gravitational pressure for our previously tall and upstanding bodies to deal with and to do so would involve a lot more energy to resist it.

A super-sized big fat Earth would be the proud possessor of a super-strong field of gravity. Nice! But unfortunately, this would mean we would have the not-so-nice job of having to deal with a decidedly unwanted increase in the number of head-on collisions with thoroughly undesirable asteroids. Lots of them!

“As a superplanet, Earth’s greater gravitational pull would effectively attract more and larger asteroids, so “Armageddon-type” collisions would become more of a concern than they are now” – Rory Barnes, theorist studying planet habitability at the University of Washington

If our super-Earth was around 10 times bigger than its normal, perfectly reasonable size this could set-off a whole bunch of spectacular changes inside our cosy, if not rather overly large planet. The Earth has a core made of iron and boasts a liquid mantle on its outside. Due to its largely unexplained and somewhat curious upgrade to a super earth both the core and the mantle would also swell proportionally, to be 10 times their normal size – eek! Not to be out done gravity would increase 10-fold leading to a pressure increase beneath Earth’s surface. This could lead to solidifying of the iron core.

Magnetic Fields

Normal size, squidgy, little Earth has a semi-liquid core complete with convection currents and it is from here Earth’s magnetic field is generated. Magnetic fields are quite handy things to have hanging around therefore, should Earth’s friendly little core decide solidifying was a pretty cool idea we would be faced with a highly unfavourable problem. The convection currents, along with the trusty magnetic field (planetary shield) could become much weaker than they are on normal sized Earth, or worst-case scenario, could disappear altogether, which is seriously bad news for every life form that calls Earth its home. Ooh err!

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Image Credit: Free stock photos – pexels.com (Image contains 2 photos)

 

 

 

Volcanic Activity

Another question with our shiny super-sized earth with its newly enlarged interior is the potential for a dangerous upsurge in volcanic activity. The expanded core contains higher levels of energy than little normal sized Earth but now it would have fewer outflows for all this extra energy it has gained, leading to more volcanic eruptions. (Jupiter’s volcanic moon Io comes to mind at this point!)

Our plate tectonics, would be different too. A larger and therefore much hotter mantle might increase convection current activity, also increasing plate movement. Alternatively, the high pressure might meld the crust together meaning there would be no plate tectonics at all.

Steam Planet

In fact, there are no guarantees that any form of life would be able to exist on our great big super-Earth. Most super-Earths detected by the Kepler space telescope were situated at nearly the same distance to their star as Mercury lies to our sun. (Think furnaces!) In this scenario our newly super-sized Earth would turn into a giant steamy planet!

References: https://www.livescience.com/what-if-super-earth.html