Archive for the ‘Magnetic fields’ Tag

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

Wolfie Chew-Sticks! You Turned the Air BLUE!!!!   35 comments

Interstellar Tourist Alert! Blue Auroras on Mars!

Don’t Miss This Fantastic Opportunity to see “The Southern Lights” of Mars!

Mars blue aurora wolf_Image credits (background): NASA/JPL-Caltech/MSSS and CSW/DB.

Theoretically it should be impossible for Mars to experience auroras as unlike Earth it no longer has a global magnetic field. On Mars it ceased to exist 3.5 billion years ago. However, in the main in the Southern hemisphere an assortment of “increased magnetic fields” have survived in the surface. These are known as “crustal magnetic anomalies,” and it would seem that these are capable of sparking auroras.

Auroral Glowing Blue Sky_

Sunrise/Sunset Auroras lighting the Wolves of MarsAurora’s appear on a relatively frequent basis after periods of intense solar flare-ups during the life of a solar cycle which on Mars causes  a beautiful, glowing blue sky.  For the intrepid interstellar tourist chasing the Martian lights jumping out of bed bright and early is recommended as they are best caught just before sunrise.

Alternatively for the lazy, late-rising tourist who probably prefers a Martian cocktail on the blue-soaked beaches whilst lounging in a deck chair watching the sun go down, just after sunset is the ideal time to catch the spectacular Martian lights.

  •   On Mars, aurorae also occur in the visible range.
  •   Carbon dioxide in Mars’s atmosphere means skies glow intense deep blue.Southern Skies glow an intense deep blue

Mars’s atmosphere consists mainly of nitrogen and carbon dioxide. Consequently the southern skies glow an intense deep blue. On Earth the oxygenated atmosphere causes auroras in shades of red and green – the Northern Lights. It is still possible to see such colours, though in far more subdued tones, on Mars too.

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The research also hopes to help us understand:

  •   More about the atmospheres of other planets and their emissions, and also that of Earth.
  •   The evolution of the Martian atmosphere
  •   Difference in mass between Mars and Earth
  •   Assisting in the ultimate discovery of habitable new worlds

Blue aurorae in Mars’ sky visible to the naked eye_Background Image Credit: NASA/JPL-Caltech/MSSS and CSW/DBBrave new worlds millions of miles from home

”Prime view of the aurora may seem trivial. And yet, on cold, barren planet millions of miles away, one beautiful reminder of home could make a world’s difference.” (Quote Credit: motherboard.vice.com)

Sources:

The Sky at Night
NASA.gov
Motherboard.vice.com
Astronomy Now.com
Washington Post