What is at the edge of the solar system?
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| Image credit: istockphoto.com |
We humans have discovered a lot in the field of astronomy. We know everything from lifelike exoplanets to explosive solar winds. We have studied the black holes, the neutron stars and even the fabric of cosmos. But do we know our own boundaries? I mean, do we know where does the solar system end and what is at the edge of it? Let's see...
How far have we studied the solar system?
Solar system is our closest neighborhood. It simply means that we should study it intensely than any other astronomical thing. But it turns out that solar system is the thing that we have studied the least. Scientist even don't know where does the solar system end and what is at the edge of it.
Is Pluto the edge of our solar system?
Earlier it was a common belief that the farthest planet in the solar system is the edge of it. And Neptune or Pluto was considered as the edge of our solar system. But considering the recent studies, it turns out that if you consider the edge of the solar system as the end of the planets like the orbit of Neptune or Pluto, then you are missing a lot of the solar system. Yes! Studies suggest that 90% of our solar system starts where the planets end.
Is Kuiper belt the edge of our solar system?
The Kuiper belt was discovered in the 90's and the extent of solar system doubled ever since then. It is very similar to the asteroid belt between Mars and Jupiter, but the Kuiper belt is made up of icy objects. You might expect that because the objects in the Kuiper belt are made up of icy objects, the objects should shine brightly like the distant stars. But then why can't we see the objects of the Kuiper belt? The surface of the objects of Kuiper belt is blackened due to the sun. So it is difficult to spot these objects. Besides this, these objects also do not have light of their own and they are very small as compared to stars.
What is the heliosphere?
But due to sun's magnetic field, which is equally influential beyond the Kuiper belt, a defensive shield called as the heliosphere has been created. This defensive shield protects us from harmful charged winds and cosmic rays. Without this heliosphere, our solar system won't boast life as the harmful cosmic rays which travel with the speed of light are so powerful that it can even tear apart electrons coming in its way. Heliosphere is made up of charged particles that deflects these cosmic rays and protects us. So without heliosphere, we won't exist. But is it the edge of our solar system? Shortly- NO.
What is the heliopause?
Launched in 1977, NASA's Voyager 1 is currently beyond the heliosphere in the region called as the heliopause. Heliopause is a region where the interstellar (the region in space where there is no influence of any star) and the heliospheres's outer reaches interact. Voyager 1 also sent us a surprising information that the outer reaches of the heliopause has a bubble like magnetic field. The sun's line of magnetic field gets tangled up by the time it reaches in the heliopause. Thus it forms giant bubbles of magnetic field and these bubbles are so huge to imagine.
What is the Oort cloud?
But Voyager 1 has still many decades to exit the solar system. That is because heliopause is not the edge of the solar system. We knew that 'something' is out there, beyond the planets, where sun's rays are weak but its magnetic field is still working. That 'something' beyond the planets and beyond the Kuiper belt keeps sending us visitors called as comets even today. The existence of that something was first theorized by a Dutch astronomer Jan Oort. For thousands of years, astronomers have been seeing comets travel close to the Earth. The observations led to many paradoxes regarding the origin of comets. Jan Oort knew that if the surface of comets vaporizes before coming close to the sun, it means it has formed very far away. So, seeing the observations, Jan Oort suggested that beyond the planetary section, there is a large reservoir called as the Oort cloud, of icy objects which sends short and long-period comets.
Now we know that the Oort Cloud is the edge of the solar system. But what causes the disturbance in the Oort cloud which causes the comets to come in the solar system? There are only theories about this but the real reason is unknown. So let us wait...
Posts before October 2021 have been marked as "Old Posts". Less likely, but they might have out dated or incorrect information, ugly looking bits of code, no labels, etc. Don't get me wrong, many of these posts are top-notch and interesting too.
I thought it would be better not to delete or revamp these posts, even if they suck. The bitter truth is that old works always suck, but I take that as a positive tool to convey that I am growing. Besides there's no better way to showcase my journey without these old, messy, poorly written posts!
I thought it would be better not to delete or revamp these posts, even if they suck. The bitter truth is that old works always suck, but I take that as a positive tool to convey that I am growing. Besides there's no better way to showcase my journey without these old, messy, poorly written posts!
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