Astronomy Quiz 5/30/2019 :)
What is the life cycle of a star?
1.) Begins with a nebula 1.5.) A failed star (a brown dwarf) never has enough mass to become a star. 2.) Eventually a low or high mass protostar is formed when the dust of the nebula gets hot enough for nuclear fusion to start 3.) Turns into a low, medium, or high mass star 4.) When the main sequence star (low, medium, or high mass star) starts to run out of hydrogen fuel it becomes a red giant or supergiant 5.1.) Red Giants' outer parts start to grow bigger and drift into space creating a cloud of gas known as the planetary nebula. The blue-white hot core of the star turns into a white dwarf. The white dwarf will run out of fuel and dies as a black dwarf 5.2.) A Red supergiant explodes as a supernova. 6.) After the supernova the left over materials turn into a neutron star. The really big stars, that are at least 20X our sun, turn into black holes. How the star dies depending on what type of star it is *The larger the star, the shorter it's life because the larger *
How long has the Hubble Space Telescope been in orbit?
29 years, since 1990.
What is a binary star?
A binary star is a system in which two stars are bound together by gravity; these two stars circle each other around a central point in the same way that the moon revolves around the earth.
What is theorized to be at the center of the Milky Way Galaxy?
A black hole.
What is the event horizon?
A boundary around a black hole beyond which no light or other radiation can escape.
What is the accretion disk? (not on the quiz but I thought you'd like to know jic)
A dislike flow of gas, plasma, dust, or particles around any astronomical object in which the material orbiting in the gravitational field of the object loses energy and angular momentum as it slowly spirals inward. It can steal matter from nearby stars (image). It shoots x-rays. It's the visible part of the black hole itself.
What is a singularity?
A tiny point which contains all of the black hole's mass in an infinitely small space, where density and gravity become infinite and space-time curves infinitely, and where the laws of physics as we know, cease to operate.
Why is the brightest star the brightest.
Because it's the closest to us.
What are the three possible final stages of a star?
Black Dwarf, Black hole, Neutron Star.
What two elements make up the majority of stars?
Hydrogen and Helium
How does a red giant form?
It grows from a main sequence star because as the main sequence star loses fuel and gravity it expands.
What is the name of our galaxy?
Milky Way Galaxy
Will the constellations we know now be visible in the future?
No because the stars are moving.
Can we be certain that our current description of our galaxy is correct?
No because we can't see our own galaxy. We can't see our own galaxy because we haven't been able to launch a telescope beyond our galaxy yet. (we haven't even been able to go outside of our solar system).
Do stars move during the night?
No, the earth moves.
How does the sun make energy?
Nuclear fusion. Nuclear fusion turns hydrogen atoms into helium atoms by hurdling them towards each other at *very high speeds and the energy from that transformation is the energy of the star, and fight against gravity.
Compare the size of our Sun compared to other stars
Our sun is smaller than giants and red giants, larger than white dwarfs, and it is a main sequence star. (medium)
Give an example of a constellation
Pisces
What type of galaxy do we think the Milky Way is?
Spiral
Describe the Hubble Deep field image process.
The Hubble Deep Space field image was taken by the Hubble space telescope over ten days. The telescope was focused on a small area the size of a grain of sand held at arm's length that seemed empty when seen by the human eye. The Final image was of *many* galaxies.
What is the H-R diagram?
The graph showing the absolute magnitude (brightness as seen from the earth) plotted against the surface temperature for a group of stars. The temperature side goes from hot to cold (in reverse of the norm) and the luminosity goes up.
What determines the final stage of the star?
The size/mass of the star.
What is the brightest star in the night sky?
The sun.
What do Greek letters associated with stars in the constellation indicate?
They represent how bright they are. Alpha (A) is the brightest and Zeta (Z) is the least bright.
What happens to time in a black hole.
Time slows down in a black hole.
What are the different stars located on the H-R diagram?
White dwarfs, Main sequence, Giants, Super Giants.
Do we see different stars at different times of the year?
Yes, because the earth is moving around the sun so we're in different locations.
What would a trip into a black hole be like? What would happen if you fell in.
You would eventually reach the speed of light and then you would start to feel slower even though your not. Then you would get stretched out and spaghettified.
What is a constellation?
a group of stars in an area of space (people have assigned groups of stars patterns but they don't really look like what they were assigned)
What is the sun made of?
hydrogen and helium