Ron Delvaux asks: Why aren’t there stars individual or small groups found in between Galaxies? (Intergalactic) Have they all been swept up into the area of galaxies and globulars? I’m thinking of the space between lets say us and M31 and us and M33. If there were any would they be too small or faint to see?
Ron, for many years it has been believed that both stars and planets form around their galactic cores (and its strong gravitational pull spreading out to create galaxies like the Milky Way around 110.000 light years in diameter) and stars respectively. Gravity plus angular momentum are the main elements behind stellar and planetary formation. When large clouds of gas are pushed and compressed by a nearby supernova explosion or other event that affects a dense region of gas, this process begins and after millions of years these clouds become denser at certain spots and there is enough mass and pressure to ignite a star. At some point, proto-planets also start forming from the accretion disc around the star. That makes sense with what we observe as “empty” space between galaxies….
Recently though, we have found not only that there are stars in that intergalactic “empty” space but we have also found planets (inside the Milky Way) that are not attached gravitationally to any star.
Such stars called rogue or hypervelocity stars have been discovered in the last couple years and basically have been ejected out the Milky Way. Here is a link to some information on this:
In some cases, stars near the galactic center may orbit a massive black hole at super high speeds and be ejected completely from it’s mother galaxy, traveling for billions of years in inter-galactic space. Imagine how night would look like in a planet around that star, not a single star in sight in the night sky, just a black dark sky with specs of faraway galaxies or maybe a full sky filled with the view of a nearby galaxy surrounded by dark starless sky.
Also there is evidence that stars form between galaxies:
Now, since we know that galaxies interact gravitationally (and that they will collide in the future and have collided in the past), in some of those collisions, tendrils of hydrogen may be left in between those galaxies and star ignition may be started within those clouds.
We hope we have answered your question and that the links can get you more in depth information of this wonderful topic of stellar formation. Feel free to send in more questions. Clear skies!!