Term
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Where is Earth located in the cosmic landscape?
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Definition
| Solar system>milkyway galaxy>local group>local supercluster>visible universe |
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Term
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How far is the nearest star and the nearest galaxy?
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Definition
Nearest star: proxima centauri, 4.2 ly away
Nearest galaxy: m31 andromeda galaxy, 2.5 mil ly away |
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Term
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How big is the Milky Way and how far are we from the galactic center?
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Definition
| it is 100k ly across, we are 26k ly from center |
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Term
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Definition
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¼ size of earth, 1/80th mass of earth |
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Term
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Definition
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mercury, venus, earth, mars, Jupiter, Saturn, Uranus, Neptune, |
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Term
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Definition
| orbit in asteroid belt between Mars and Jupiter, number in millions |
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Term
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Definition
| small icy objects, orbit outer fringes of solar system. Come from outside Neptune in the kuiper belt and even further in the Oort cloud |
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Term
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Definition
| stretches 100k AU from the sun |
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Term
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Definition
- 100k ly across
- more than 200 billion stars
- spiral disk galaxy
- massive black hole (dead star) at center
- consists of central bulge, disk, halo and globular clusters
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Term
Interstellar medium, Nebula: |
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Definition
| stars intermingle with immense clouds of gas and dust (interstellar matter) = Nebula |
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Term
Galaxy clusters, superclusters: |
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Definition
| There are a few dozen galaxy clusters. We are in the local supercluster (50 million ly across). |
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Term
Local Group, Local Supercluster: |
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Definition
| We are in the local group within the local supercluster (consists of local group, m101 group, virgo cluster, m81 group, and ursa major cluster) |
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Term
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Definition
- largest astronomical object of which we know
- 13.8 billion years old
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Term
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Definition
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Term
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Definition
| 93 million mi, dist between earth and sun |
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Term
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Definition
| dist light travels in 1 year, 6 trillion mi |
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Term
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Definition
| cluster of solar systems and stars |
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Term
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Definition
| Oort cloud (farthest object in solar system) stretches 100k AU from Sun |
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Term
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Distance to nearest star:
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Definition
| Proxima Centauri, 4.2 ly from sun |
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Term
| Solar system in the Milky Way |
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Definition
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Term
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How is distance and time related when observing the electromagnetic spectrum of objects in the universe? |
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Definition
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