Stars are not extragalactic objects because they are part of our own Milky Way galaxy. Galaxies, quasars, and nebulae are all examples of extragalactic objects.

All of the mentioned telescopes are used to observe extragalactic objects, depending on the specific wavelengths of light or radiation being studied.

Galaxies are the most common type of extragalactic object, consisting of vast collections of stars, gas, and dust bound together by gravity.

IC 1101 is the largest known galaxy in the universe, with a diameter of approximately 6 million light-years.

GN-z11 is the most distant object ever observed by astronomers, located approximately 13.4 billion light-years away.

Sagittarius A* is the name of the supermassive black hole at the center of our Milky Way galaxy.

Redshift is the term used to describe the phenomenon where distant galaxies appear to be moving away from us, causing the light they emit to shift towards longer wavelengths (redder colors).

TON 618 is the largest known quasar in the universe, with a diameter of approximately 100 light-years.

Galaxy merger is the term used to describe the process by which galaxies merge and combine to form larger galaxies.

The Andromeda Galaxy, also known as M31, is the nearest major galaxy to our Milky Way.

Gravitational lensing is the term used to describe the phenomenon where the light from distant galaxies is distorted and stretched due to the gravitational field of a massive object.

Abell 2218 is the largest known galaxy cluster in the universe, containing thousands of galaxies.

Dark energy is the term used to describe the phenomenon where the expansion of the universe is accelerating.

The Cosmic Background Explorer (COBE) was launched in 1990 to study the cosmic microwave background radiation.

The Wilkinson Microwave Anisotropy Probe (WMAP) was launched in 2003 to study dark energy and the expansion of the universe.