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N e b u l a
Ever wondered where stars are made? Well, now you are about to find out! Just where these hot balls of gas start their
lives begins in what astronomers call a nebula (plural: nebulae) and they are basically the nurseries of the Universe.
PRIMARY SCHOOL "VASIL APRILOV" - RUSE
DIVE IN THE SKY
For one, a nebula is a gigantic cloud of dust and gas; mainly of hydrogen and helium gases, and they can be light years across - that’s trillions of miles - imagine how many nurseries you can fit into one of these ginormous star factories! Secondly, they look quite fuzzy in appearance - pretty much like fluffy clouds or cotton wool in the sky.
Nebulae come in not just a variety of sizes, they also come in a range of shapes with some of them looking very much like anything from horses (the Horsehead Nebula) to crabs (the Crab Nebula). The massive question is though, how do they form or have they always been there? What do you think?
When it comes to making stars, astronomers believe that nebulae are made from the huge collapse of gas in what they refer to as the Interstellar Medium (the gas, dust and cosmic rays that can be found between planets and stars in galaxies). As the material falls in on itself under its own weight, large stars are made in the centre. When this happens, ultraviolet radiation shoots out like a laser beam and the nebula is lit up - just like a Christmas tree! Astronomers have a name for these types of nebulae – “EMISSON NEBULAE”
An emission nebula is a nebula formed of ionized gases that emit light of various colors. The most common source of ionization is high-energy photons emitted from a nearby hot star.
Sometimes, stars do not have enough pent-up energy to zap their surroundings with high energy particles. So they happily sit in clouds of dust and these clouds reflect their light. This light is reflected and that’s pretty much what happens in a reflection nebula.
That’s not the end of our tour of nebulae - there’s more! Last but not least there’s planetary nebulae - but do not be fooled - these shells of gas have absolutely nothing to do with planets! This type of nebula earns its name because some astronomers of the 18th Century believed that they looked like giant worlds through the eyepiece of small telescopes.
Planetary nebulae are made when a star runs out of fuel to burn. What happens next is amazing. It’s not quite the same as when your car runs out of gas, where it stops moving - what happens to a star is quite a bit different; it blows off its outer layers of gas in the shape of a ring or bubble. When stars do this, astronomers say that a star is dying. But it’s not a sad ending for the star, it’s a beautiful colorful one!
NEBULA AND STAR BIRTH
PREPARING…
We watched our Turkey`s friends activities and we did it…
WE HAD A LOT OF FUN!
https://en.wikipedia.org/wiki/Nebula
https://en.wikipedia.org/wiki/Emission_nebula
https://en.wikipedia.org/wiki/Planetary_nebula
https://en.wikipedia.org/wiki/Reflection_nebula