Table of Contents
How old are spiral galaxies?
eleven billion years old
The oldest spiral galaxy on file is BX442. At eleven billion years old, it is more than two billion years older than any previous discovery. Researchers think the galaxy’s shape is caused by the gravitational influence of a companion dwarf galaxy.
Do spiral galaxies have old stars?
Classic or barred notwithstanding, all spiral galaxies can broadly be described visually as having a central bulge of old stars surrounded by a flattened disk of young stars, gas and dust.
What is at the Centre of a spiral galaxy?
Most spiral galaxies contain a central bulge surrounded by a flat, rotating disk of stars. The bulge in the center is made up of older, dimmer stars, and is thought to contain a supermassive black hole. Approximately two-thirds of spiral galaxies also contain a bar structure through their center, as does the Milky Way.
What type of stars are in spiral galaxies?
Spiral Galaxies It is dominated by young, blue Population I stars. The central bulge is devoid of gas and dust. As you might expect, the bulge is composed primarily of Population II stars. Type c spiral galaxies have the most gas and dust.
What is red light shifting?
‘Red shift’ is a key concept for astronomers. The term can be understood literally – the wavelength of the light is stretched, so the light is seen as ‘shifted’ towards the red part of the spectrum. Something similar happens to sound waves when a source of sound moves relative to an observer.
How big are black holes?
Stellar black holes, the most common, have a mass 20 times the size of the sun but are condensed in a 10-mile diameter sphere. Finally, supermassive black holes have masses of more than one million suns compressed into a sphere as giant as the solar system.
What is the most rarest thing in the universe?
“At” stands for astatine. It is an element with 85 protons packed into its nucleus, thus the atomic number “85” The problem is, there’s something about 85 protons in a tight space that nature doesn’t enjoy. Almost as soon as they squeeze together bits of nuclear material get spat out, or get added, and poof!
What is Z in astronomy?
z tells you the number of years the light from the object has traveled to reach us, however this is not the distance to the object in light years, because the universe has been expanding as the light traveled and the object is now much farther away.
How close have we gotten to a black hole?
In 2020, a team of astronomers with the European Southern Observatory (ESO) discovered the closest black hole to Earth in the HR 6819 system, just 1,000 light-years away, only to have other scientists dispute the findings.