Formation & Motion of Galaxies and Stars Flashcards
Gravity's Effect on Galaxies & Stars, Characteristics of Stars, The H-R Diagram, and Stages of Stellar Evolution (24 cards)
Gravity’s Effect on Galaxies & Stars
Explain how gravitational force forms stars & galaxies.
Debra’s Hint: It pulls two thing that makes enough mass
(Optional to flip if needed)
During the early stages of universe, gravity pulls gas and dust particles, with enough mas to form a star.
- Many stars = Galaxy
Gravity’s Effect on Galaxies & Stars
What are the different types of galaxies?
Debra’s Hint: (My term) S.E.I.L Galaxies
(Optional to flip if needed)
Types of Galaxies:
Spiral galxies:
- Consists of a central, dense center (nucleus) surrounded by flattened windings arms
- They can be normal or barred
Lenticular Galaxies:
- Similar to spiral galaxies, but lack the spiraling areas
- Consists of a central, dense center that is surrounded by a flattened disk of gas & stars
Elliptical Galaxies:
- These galaxies have a spherical or ovoid shape
- Mostly made of older, low-mass stars and little to no interstellar gas
Irregular Galaxies:
- These galaxies have a distinctive, regular shape shape (blob).
- They don’t appear to rotate
Gravity’s Effect on Galaxies & Stars
What kind of galaxy is the “Milky Way” Galaxy?
Debra’s Hint: It’s one of the types of galaxies.
(Optional to flip if needed)
The Milky Way Galaxy is a Barred spiral galaxy
Gravity’s Effect on Galaxies & Stars
What can be found in the center (nucleus) of galaxies?
Debra’s Hint: Bla..ho.. (Strange but helpful)
(Optional to flip if needed)
In the center, you can find supermassive blackholes.
Gravity’s Effect on Galaxies & Stars
Explain what effect gravitational force has on Hydrogen in the core of stars.
You can flip this! but, you should make sure to memorize.
Gravity pulls hydrogen atoms toward the center compressing them in extreme pressure and temperature. The intense pressure forces hydrogen nuclei to fuse together nuclear fusion (the process that powers stars).
Gravity’s Effect on Galaxies & Stars
Explain why astronomers believe that the Universe is expanding.
They believe it is expanding because the…. a galaxy is, the….
(Optional to flip if needed)
They believe it is expanding because the farther a galaxy is, the faster it’s receding = space strengthing overtime. -> From the center of the universe
Characteristics of Stars
What is the color order of the surface temperature scale for stars from coolest to hottest?
Debra’s Hint: We start R and B/V
(Optional to flip if needed)
Red (coolest), orange, yellow, white, (hottest) blue/violet
Red = 2000 celcius
Blue/Violet = (Upwards of 50,000 celcius)
Characteristics of Stars
How does distance, size, and temperature affect a star’s magnitude?
You can flip this! but, you should make sure to memorize.
Distance: The farther away a star is, the dimmer it appears to us.
Size: Bigger stars shines bright because they have more surface area to give off light. Giant stars will appear brighter than small stars of same temperature.
Temperature: Hottest stars glow with higher energy, meaning they shine more intensity. Blue stars, which are the hottest, tend to be much brighter than cooler red or yellow stars.
Characteristics of Stars
What is the difference between apparent magnitude and absolute magnitude?
Debra’s Hint: How we see.. what it really is..
(Optional to flip if needed)
Apparent magnitude: This is how bright a star looks to us. A closer star might seem brighter than a faraway, powerfuk star becauses its nearer.
Absolute magnitude: The stars true brightness, measured as if all stars were placed at the same distance (astronomers compare brightness of actual stars).
- Both ways of measuring the stars magnitude
The H-R Diagram
According to the H-R Diagram, what relationship is there between temperature & brightness with small stars?
Debra’s Hint: Depending on temperature and brightness
You can flip this! but, you should make sure to memorize.
Small stars: Increase in brightness as temperature increases.
Low-temp & Low Brightness = Tend to be cooler and dimmer.
High-temp & High Brightness = Tend to glow more intensely like a white Dwarf.
The H-R Diagram
According to the H-R Diagram, what relationship is there between temperature & brightness with large stars?
Debra’s Hint: Depending on temperature and brightness
You can flip this! but, you should make sure to memorize.
Large stars: Tend to maintain their brightness as tempature increase.
Hotter/Brighter: Massive stars tend to be hotter because they burn fuel rapidly
Cooler/Dimmer (But still powerful): Some large stars like red supergiants, have lower temperatures but are huge in size despite temperature.
Note: On the H-R Diagram, the largest stars (supergiants) are mear the top. Meaning, they are incredinly bright despite if they aren’t the hottest (LOL, how realistic).
The H-R Diagram
According to the H-R Diagram, what classification is given to 90% of discovered stars?
Debra’s Hint: M.S.
(Imagine fliping to see the right answer before answering this easy question💀)
About 90% of the discovered stars belong to the MAIN SEQUENCE!!!(👹) ✨cLaSsIfIcAtIoN.✨
The H-R Diagram
What is the classification of the Sun according to the H-R Diagram?
Debra’s Hint: Think of the color of the Sun
Another Hint: (it’s not white😭) - (Optional to flip if needed)
The Sun is classified as a G-Type main sequence star, also known as a G Dwarf or G2V. Yelllow star (Dwarf)
Stages of Stellar Evolution
What is the first stage for all stars during stellar evolution?
Debra’s Hint: Stars with a “N.”
No you can’t flip, dummy– (Smarty I mean ;))
The first stage for all stars during the stellar evolution is Nebula.
- Cloud of dust and gas
Stages of Stellar Evolution
What is a protostar?
Debra’s Hint: It’s a Young Star
(Optional to flip if needed)
A body star forming, gathering gas and dust before it starts shining on it’s on.
Stages of Stellar Evolution
What has to happen for a protostar to change to a main sequence star?
Debra’s Hint: Has to be suffice (One of Mrs. Bray’s Vocab words!)
(Optional to flip if needed)
Once its temperature + pressure become great enough to do nuclear fusion.
Stages of Stellar Evolution
Which types of stars, low-mass or high-mass, will fuse hydrogen into the Helium the longest?
Debra’s HInt: One burns faster than the other
(Optional to flip if needed)
Low mass-stars = Fuse hydrogen the slowest (tens of billions of years)
High-mass stars = Fuse rapidly or the fastest (millions, thousands of years)
Stages of Stellar Evolution
What happens to a low-mass star when it runs out of Hydrogen?
You can flip this! but, you should make sure to memorize.
(I’m cooked)
Core shrinks, outer layers expand, helium burns briefly, outer layers drift away (planetary nebula), core becomes a white dwarf.
Stages of Stellar Evolution
What happens to a low-mass star when it fuses Helium into Carbon?
You can flip this! but, you should make sure to memorize.
(I’m cooked)
Helium fusion begins (causing outer layers to expand, red giant phase (core keeps growing denser), helium runs out (planetary nebula formation), and finally white dwarf remanant.
Stages of Stellar Evolution
What is the final stage of evolution for low mass stars?
Debra’s Hint: Wh…Dw..
The final stage of evolution for low-mass stars are becoming a white dwarf.
Stages of Stellar Evolution
What happens when a high-mass fuses elements into iron?
You can flip this! but, you should make sure to memorize.
Iron fusion stops energy production (fusing iron doesn’t release energy), core collapses rapdily, massive supernova, and either becomes a neutron star or a black hole.
Stages of Stellar Evolution
What is a neutron star?
Debra’s Hint: Opposite of the size of a Black Hole
(Optional to flip if you need to)
Is super dense, incredbily small leftover core of a massive star after supernova.
Stages of Stellar Evolution
What is a black hole?
Debra’s Hint: Opposite of the small size of the Neutron star
(Optional to flip of you need to)
Is even more extreme leftover, where gravity is so strong that nothing; not even llight can escape.
Stages of Stellar Evolution
What stages of stellar evolution will the Sun go through and how will it sun?
You can flip this! but, you should make sure to memorize.
Main sequence, Red Giant, Planetary nebula, and then a white dwarf.
