Table of Contents
Why do we study distant galaxies?
By observing more distant objects, we look further back toward a time when both galaxies and the universe were young (Figure 1).
What tells scientists about distant galaxies?
What does the light astronomers observe through telescopes tell them about distant galaxies? magnitude.
How do we study distant galaxies?
Very distant galaxies have very large recession velocities — they are moving away at a good fraction of the speed of light. This causes extreme doppler redshifts, which means that distant galaxies are brightest in the infrared part of the spectrum. To observe these, we need to put large infrared telescopes into space.
What are the benefits of studying the galaxy and the universe?
By studying the cosmos beyond our own planet, we can understand where we came from, where we are going, and how physics works under conditions which are impossible to recreate on Earth. In astronomy, the Universe is our laboratory!
What galaxy do we live in?
the Milky Way
We live in one of the arms of a large spiral galaxy called the Milky Way. The Sun and its planets (including Earth) lie in this quiet part of the galaxy, about half way out from the centre.
Can galaxies form without dark matter?
Without dark matter, galaxies would lose a large fraction of the gas that forms new stars immediate after the first major star-forming event they experienced.
How do we know there aren’t antimatter galaxies?
A simple way to test and see if there is anti-matter around is to send out a ‘detector. ‘ In this case, it is completely trivial to make a detector: it simply has to be made of matter! Any time matter collides with anti-matter, the two annihilate and produce lots of gamma rays.
What happens when two spiral galaxies collide?
A: When two spiral galaxies collide, gravity is the main force that comes into play. As the galaxies approach each other, gravitational forces start to pull the stars, gas, and dust of the spiral arms out of their original orbits. During the merger, the stars become scattered and their orbits become random.
Where would you look for the youngest stars in the Milky Way galaxy?
These are the youngest stars found in the Milky Way’s bulge, outside of the nuclear star cluster surrounding the supermassive black hole. Interestingly, these Cepheids live in only a restricted region of the sky.
What can we learn from studying galaxies?
Through probing the extreme environments of faraway massive galaxies, we can learn not only about their evolution and the history of the universe, but most importantly about the fundamental processes regulating the formation of stars.
How many galaxies are they?
One 2016 study estimated that the observable universe contains two trillion—or two million million—galaxies. Some of those distant systems are similar to our own Milky Way galaxy, while others are quite different.
Which is the most beautiful galaxy?
NGC 2336 is the quintessential galaxy — big, beautiful, and blue — and it is captured here by the NASA/ESA Hubble Space Telescope.