Telescope of this generation

Hi,
this title is kind of weak, I know that, but I did not want to write “rusty, old piece of metal”. First because rusty could be a little bit misleading, rust only occurs when there is oxygen and there is only little of that in space, more accurately there is 1% of all the atoms in the Universe which is quite few tons but at the same time Hubble Space Telescope is flying in near vacuum when there are just a couple of hydrogen atoms per cubic meter, maybe in his lifespan he even touched few oxygen atoms. Second because he just does not deserve it. (Check out the post about James Webb Space Telescope)


His lifespan? Well it has been a long for such an instrument which are usually meant to work for much less years. For now the telescope has been working for 25 years, 9 months and 29 days. It is assumed that it might work for another 20 years or so, it could be even longer but it is slowing down and as I explained in post about orbits, it will eventually fall down and burn up in atmosphere. Not that this space telescope would be half immortal or so, but it was able to work for so many years because there were actually missions to repair some of its tools and power systems, otherwise it would not work by now [1].

When Hubble was launched and first images sent to NASA they were good, but not good enough which was because of the mirror. It was polished to a little bit wrong shape so they had to repair that. Before they did it NASA used some complicated image processing to get the best out of those pictures.

The repair itself was very complicated since replacing mirror was simply impossible and to bring the telescope back was too expensive. They solved it by making the same mistake but “of opposite direction” on another part of the telescope so it was totally canceled out, you can check out on the next picture to see how much it made a difference:

 

One of the images taken during the misson for some repair.

Pillars of creation, by Hubble

NASA even decided to borrow some of Hubble’s time for amateur astronomers, of course it was not easy to get that time but it was definitely worth it I am sure.

Hubble is not justing taking those beautiful pictures but it also helped to measure Hubbles constant on whole next level and also through his data we found out that the expansion of Universe is actually increasing, phenomenon which is not well understood but most people think that it is because of dark energy.

This is monstrosity, almost all of those bright points are galaxies, galaxies which we will most probably be never able to search through.

Hubble also helped with some observations of black holes and also as you can see above, Hubble made a whole new picture of the youngest parts of Universe, so extremely far away.

Depiction of progress in the detection of the early Universe

How far can we actually see?[2]

Dragallur

[1]Actually it is the first such thing in space that was repaired by humans which is actually pretty cool.

[2]Check out this post to read about red shift, the x axis on the picture.

All pictures from here and here

 

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The riddle of DARK MATTER! (Part 1)

Hi,
I can not believe it took so much time to finally write about dark matter since I knew about it such a long time and thought that I should write about it some time.
Now because dark matter has to do a lot with gravity (and only gravity) then I just have to share with you this meme:


 

OK, enough fun for now, lets see what this dark matter is.

How did we find it?

Once upon a time one great scientist was born and her name was Vera Rubin. It happened in kingdom (federal republic) far far away, over one big ocean and no mountains. Vera wanted to be astronomer since her 10 years. When she signed up for some school they asked her if she does not want to draw space objects since she liked to draw, this was because in 40s female scientists were not very common.

Finally she was able to start to work and with new age of better telescope she began with huge observation. Most people used those telescopes to look at active cores of galaxies and such exciting places but Vera with her colleague[1] Ford rather observed the outskirts of galaxies and they saw very interesting thing, these outskirts were moving way too far.

As object get away from the thing they orbit (as in our Solar System) they tend to orbit slower.

  1. Mercury 47.36 km/s
  2. Venus 35.020 km/s
  3. Earth 29.783 km/s
  4. Mars 24.077 km/s
  5. Jupiter 13.050 km/s
  6. Saturn 9.638 km/s
  7. Uranus 6.795 km/s
  8. Neptune 5.432 km/s
  9. Pluto 4,666 km/s (oops not a planet :D)

So as you see the orbit speed really decreases, this is because there is lower force of gravity so the planet does not need to be so fast to make these forces equal.

In galaxies this should happen too but it does not!

Now here comes the theory of dark matter which is spread over whole galaxies and there is tremendous amount of it making those stars in the outskirts to go faster than they should.

There are only 4% of ordinary matter the one which we know about a lot.
21% is dark matter and 75% is dark energy as you can see on the next picture:

The only thing we know about dark matter is that it interacts with ordinary matter through gravity. We can measure this and measure how much and where it is, also we know that it does not tend to create some piles like normal matter so it seems that there are no dark matter stars. As Sean Carroll says in his book Particle at the End of Universe, dark matter is a clear example of something beyond the standard model of particles.

Dragallur

[1] At first I wrote collieg instead of colleague, it took me a long time to figure the spelling out even using the corrector in Chrome, I think this will make one of my friends really really happy!

19.1.2016 I made second part so click HERE to read more about dark matter.