How Our Place in the Galaxy Affects Life on Earth

In summary, it seems that there are many potential "stresses" that our Solar System could experience, which could have an effect on Earth's climate. However, it is difficult to say for certain which factors are the most important in causing these changes.
  • #1
Bobby R
11
0
Something important to think about:
If it takes us between 225 and 240 millions years to make one Galaxy orbit wouldn’t it be prudent to associate magnetic polar shift, global warming, and ice-ages to where the sun was located when these events occurred? Were we close to or farther away from something which had an effect on our sun? Could events such as Continental drift/shift be a part of the equation? Something to think about.
Bobby R. asks…J
:tongue2:
 
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  • #2
Not really. The times between ice-ages, polar shift, global warming, etc. is considerably less than 225 million years.
 
  • #3
It is my understanding that the particular phenomena you mentioned did not happen at regular intervals. However, mass extinctions do seem to occur at evenly spaced periods of opportunity, and the spacings roughly correlate to one half of a galactic orbit. This has given rise to the theory that mass extinctions are tiered by the perturbative effect of our solar system passing through the thickest part of the galactic disk (twice every orbit).
 
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  • #4
LURCH said:
(twice every orbit).
It actually does it more than twice an orbit. I'm not sure of the dynamics, but its not the same as a planet passing through its ascending and descending nodes. The Sun bobs up and down more than this.
 
  • #5
There is not a simple answer. The variables seem to increase the more I read.
Interestingly, our Sun oscillates in and out of the plane of the galaxy (up and down) every 70 million years (approx.). Which means we pass through the Galactic mid-plane about every 35 million years. The number of cosmic rays which hit the Earth increases during the near hundred thousand years we are closest to the Galactic plane. What happens to Earth’s temperature during this transition through the mid-plane? Could one assume influence on Earth’s magnetic field as well?
Our Sun is located in a small spiral arm we call the Orion arm (or local arm) which is really a connection between the two nearest major spiral arms (Sagittarius and Perseus). We pass through a major spiral arm about every 100 million years taking about 10 million years to go through. During the transit, there would be a higher rate of ’nearby’ supernova and possible other ’environmental stresses’ which could alter the climate of Earth.
Simply put, as our Solar System travels in Galactic orbit there are many potential stresses we can speculate ‘cause and effect’ from. Along with our Sun there are approx. 400 billion other celestial bodies in the Milky way.
 
  • #6
Bobby R said:
Interestingly, our Sun oscillates in and out of the plane of the galaxy (up and down) every 70 million years (approx.). Which means we pass through the Galactic mid-plane about every 35 million years. The number of cosmic rays which hit the Earth increases during the near hundred thousand years we are closest to the Galactic plane. What happens to Earth’s temperature during this transition through the mid-plane?
There are some hypothesis that the passage through dense interstellar clouds could pertub the heliosphere increasing the production of anomalous cosmic rays which reach afterwards the inner of the solar system. These cosmic rays could lead to some chemical reactions on the earth’s atmosphere contributing to the dissociation of ozone and thus leading to an increase of the UV radiation from the sun that reaches the Earth's surface. This radiation has an effect on the genetic code. Also, the passage through the most dense zone of the galatic plane could perturb Oort’s cloud leading to an increase in the number of comets traveling towards the inner solar system.

I have no references about both at hand, but I am sure you can find about these in google (I remember to have read about both in press articles).
 

1. How does the position of Earth in the galaxy impact our climate?

The position of Earth in the galaxy does not have a direct impact on our climate. Our climate is primarily affected by the tilt of Earth's axis, distance from the sun, and the composition of our atmosphere.

2. Can our place in the galaxy affect the development of life on Earth?

Yes, our position in the galaxy has played a significant role in the development of life on Earth. The location of our solar system within the Milky Way has provided the necessary conditions for the formation and evolution of life.

3. How does our position in the galaxy affect our exposure to cosmic radiation?

Our position in the galaxy does affect our exposure to cosmic radiation. The Earth's atmosphere and magnetic field protect us from the majority of cosmic rays, but our position in the galaxy can determine the intensity of cosmic radiation we are exposed to.

4. Does our position in the galaxy affect the likelihood of Earth being hit by asteroids or comets?

Yes, our position in the galaxy can impact the likelihood of Earth being hit by asteroids or comets. The gravitational pull of nearby stars and planets can alter the trajectory of objects in our solar system, potentially increasing or decreasing the chances of a collision with Earth.

5. How does the position of Earth in the galaxy impact our view of the night sky?

Our position in the galaxy does affect our view of the night sky. The position of Earth in relation to other stars and galaxies can impact the visibility and appearance of constellations, as well as the frequency and intensity of astronomical events such as meteor showers and eclipses.

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