Our own galaxy, the Milky Way, as well as other smaller galaxies-satellites of large galaxies.
Interstellar objects that are smaller than galaxies have been called Dwarf Galaxies – they contain several billion stars.
The Andromeda galaxy is not the closest to our galaxy, it is 100 times closer to us than the dwarf galaxy in the Big Dog, which is a satellite of our galaxy.
The Milky Way is currently engulfing another smaller Dwarf Sagittarius galaxy, an elliptical galaxy, one of our satellite galaxies.
Scientists explain the current structure of the Milky Way spirals by the fact that they used to be dwarf galaxies.
Scientists have suggested that if or when the Andromeda galaxy and the Milky Way collide somewhere in 3-5 billion years, the chances of two stars colliding are minimal due to the huge distances between them.
The Milky Way, together with the entire Virgo cluster, is moving in space, at a speed of 600 km/s, towards an unknown object called the Great Attractor, whose mass exceeds several tens of thousands of times the mass of the Milky Way.
Last year in South Africa, Swedish scientists discovered that dung beetles use the glow of our galaxy to navigate. And they are the first living beings, other than humans, to have a precise orientation in the Milky Way galaxy.
The apparent size of the Andromeda galaxy is four times larger than our Moon when seen from Earth, but its glow is so faint that it is almost impossible to see it from Earth with the naked eye and it looks like a faint dark mark in the night sky.
Last year, astronomers spotted the oldest and most distant galaxies ever observed, at a distance of 30 billion light-years from Earth. An international team of astronomers observed these galaxies using the Hubble telescope at the Keck Observatory in Hawaii. And the most interesting fact is that the Universe is about 14 billion years old, and astronomers see the galaxy when it was about one billion years old. The distance from the center of the universe to the Earth is about 30 billion light-years and is constantly increasing due to the rapid expansion of the Universe.
Scientists have named one galaxy the “Death Star”, because in the center of this galaxy is a supermassive Black Hole, which destroys it from the inside.
A sound from a Black Hole in the Perseus galaxy, 250,000,000 light-years from Earth, 57 octaves below the middle note To.
An unknown object in the nearby galaxy M82 reflects radio waves. This is nothing special, because these signals were reflected when the ancestors of mankind were still jumping on trees.
Due to the increasing speed at which all known galaxies are moving further apart, in a few billion years it will be impossible to distinguish these galaxies, except for their own in the night sky of the Earth.
For every person, there are 24 galaxies in the observable universe (170 billion galaxies per 7 billion people).
In areas with clear skies and no obvious pollution, the Milky Way’s glow is bright enough to cast shadows on earth at night.
The Earth and our Solar System currently pass through an area of the universe with a density of only 5% of the average density of our galaxy, and it is likely that a Supernova exploded in this area about 300,000 years ago.
As of 2011, scientists estimate that there were about 50 billion planets in our galaxy, of which at least 500 million were in the” habitable zone ” of their star. As of January 2013, the number of planets in the Milky Way galaxy is about 100 billion planets.
Supernovae explode on average once every 100 years in our galaxy. If we assume that there are about 170 billion galaxies in the universe, then 53 supernovae explode every second.
The last supernova in our Galaxy appeared in 1604.
Quasars emit thousands of times more energy than our entire galaxy.
The light in the upper part of the Andromeda galaxy is 250,000 years older than in the lower half.
Scientists have discovered a star known as S2, which orbits the supermassive Black Hole at the center of our galaxy at a speed exceeding 18,000,000 kilometers per hour.
NASA has registered the Galaxy NGC 4151 under the name “Eye of Sauron”, because of the striking resemblance to the Tolkien character.
A dwarf galaxy called “Segue 2”, the heaviest galaxy in the known universe, located at a distance of about 114,000 light-years from Earth. The galaxy is made up of only 1,000 or so stars with dark matter holding them together.