No other stars are visible to the naked eye because they're too faint. Telescopes gather much more light so they're able to see things that are much farther away (and fainter).So if the only visible stars to us are in the milky way galaxay ours, how do we get those
amazing pictures of other galaxies. Probably no stars?
I think about this stuff all the time. How the Universe Works is my favorite show on TV, and I can't think of more interesting things to think about.Oh yea……so…..try this on for size!
If the Earth were a grain of sand, then how big would the rest of the universe be in comparison?
Let’s make earth be a largish grain of sand, about 1.27 mm in diameter. This gives us a scale of 10^10 or ten billion to one. Fairly easy to make calculations this way.
All in this scale:
So scaling the earth to a grain of sand, Pluto is a 10 minute walk, local stars are a plane flight away, our local group of galaxies fits in the solar system, but the edge of the universe is way past the nearest star! A freaking big place!
- Distance to the moon: 40 mm, about 1.6 inches
- Distance to the sun (1 AU): 15 meters or about 50 feet.
- Distance to Jupiter: 78 m.
- Distance to Pluto: 600 m.
- One light year (9.5 trillion km): 950 km. BTW, this means light moves at 0.03 m/s.
- Distance to nearest star (4.22 LY): 4000 km.
- Distance to galactic center (26,000 LY): 25 million km.
- Distance to Andromeda galaxy (2.54 million LY): 2.4 billion km (but at this scale, still within our real-world solar system).
- Distance to the center of our Virgo supercluster (about 65 million LY): 60 billion km (deep in the Oort Cloud, in the real universe). There are probably 10 million superclusters in the observable universe, so we are still a big step away from the size!
- Distance to the edge of the observable universe (94 billion LY): 90 trillion km, almost 10 LY in the real universe.
I think about this stuff all the time. How the Universe Works is my favorite show on TV, and I can't think of more interesting things to think about.
One of the coolest things I've read about recently is the Hubble image of Earendel, the most distant (and therefore oldest) star ever seen. The light has traveled 12.9 billion light years (and it's now 28 billion light years away), meaning that Earendel is the first observed example of a mythical "Population III" star- one of the giants formed from the original primordial soup from the Big Bang. Population III stars are all long gone (they likely died in supernovae over 12 billion years ago due to their immense size), but through the crazy coincidence of gravitational lensing of multiple galaxies, Earendel's light was magnified up to 40,000 times, allowing us to see it!
Here's an amazing video on Population III stars- one of the most fascinating things I've watched in a long time.
I looked that up and WOW, Ton 618 outweighs our entire galaxy and is so bright we can't see it's parent galaxy, it weighs at least 66 billion times our sun which is almost 3 times the mass of Pavaroti or 2.7 Oprahs.And these stars along with ‘direct collapse’ hydrogen clouds gave us the truly gargantuan black holes of the universe. Ton 618 is an estimated 40x our solar systems in diameter!! The largest single object in the universe!!! And that was 10.3 billion years ago!!