Astronmy Exam 2

How does an atmosphere affect the surface of a planet and the ability of life to exist?

If the atmosphere is not thick enough it cannot retain heat to inhabit life and if its too thick (like venus) it will retain too much heat. this also depends on the distance from the sun. For human life a planet need a thick enough atmosphere to allow water to be a liquid

The mountains on the Moon were formed by what process?

Impact cratering. Where a large object hits the moon so hard it kinda explodes the surface around it. makes the debris fly up and land around the rim. sometimes in the center creating moutains

What is the composition of clouds on Mars?

Clouds on Mars are of three types: dust clouds; water-ice, like those on Earth; and clouds of frozen carbon dioxide crystals (dry ice)

Why does the Moon not have an atmosphere?

small bodies in space have low gravitational pull. Therefore any gas emitted from the moon would easily escape.

Explain continental drift

stuff going on inside of the earth causes the tectonic plates to move with in turn shift continents and even break them apart. RIP Pangea

What characteristics do the worlds in our solar system have in common that lead astronomers to believe that they all formed from the same "mother cloud" (solar nebula)?

(Solar nebulas are clouds of rock and gas surrounding young stars) All the planets in our system orbit on the same plane and in the same direction around the sun. The giant planets also have very similar chemical makeup as our sun.

Describe the solar nebula, and outline the sequence of events within the nebula that gave rise to the planetesimals.

(solar nebula explained in another card) Planetesimals are comounds that have come together under the right circumstances and will become a planet. At the end of a solar nebula process, material not in the center or near the star are able to cool but still collide with each other thus creating larger objects that will orbit the sun. bam a planet (plantesimals first tho)

Summarize the four main hypotheses for the origin of the Moon.

1) fission hypothesis- the moon was once apart of earth but separated long ago 2) Sister hypothesis- The moon and earth formed at the same time but not together 3)Giant object hypothesis- A very large object came into contact with earth, debris from both objects condensed and created the moon 4)Capture hypothesis- The moon was made somewhere else and drifted towards earth and got caught in out gravitational pull

What is the difference between a meteor and a meteorite?

A meteoroid is called a meteor when it is in earths atmosphere but called a meteorite as soon as it hits earth surface (think, meteoRIGHT when it hits RIGHT on the surface). Most of the time, meteors burn up in the atmosphere before they are able to make contact

How do asteroids and comets differ?

Asteroids are mostly metal and rock which are found in th astroid belt. Comets are ice and dust which orbit the sun. Heat causes the ice to evaporate which creates the tail of a comet.

Why do meteors in a meteor shower appear to come from just one point in the sky?

Comets follow a set orbit around the sun (a very large one) and since meteor showers come from the same comet (different showers are different comets. theres not 1 comet causing every meteor shower), the meteor shower will follow the same constant path as its comet that it came from

Describe the two types of comet tails and how each are formed.

Dust tail and ion tail. The dust tail is bright and glows as a result of solar energy pushing material away from the body. The ion tail or "plasma" tail is more dull and curves away. plasma tails are charged ions being pushed away by the suns solar particles

Compare the current atmospheres of Earth, Venus, and Mars in terms of thickness (and pressure at the surface), and the greenhouse effect.

Earth has a decently thick atmospere enough to create a greenhouse effect. Venus has a VERY think atmosphere that in turn causes an extreme greenhouse effect (very very hot). Mars atmosphere is much thinner than earths (so no greenhouse effect) The thicker the atmosphere the high the surface pressure. Venus has the highest surface pressure of the 3 and mars has the lowest.

Atmospheric composition of Earth, Mars, and Venus

Earth is mostly Nitrogen and some oxygen venus and mars are mostly carbon dioxide

What is the source of Earth's magnetic field?

Electrical currents from melting iron in the earths core

Which is the largest moon in the solar system?

Ganymede (to remember this think G-iant idk its 1 of 2 moons that start with the letter G)

What was the solar nebula like? Why did the Sun form at its center?

Gas and dust in an area of space. Stuff began to stick together in the center creating a gravitational pull which allowed for more gas to be pulled in and colloid with one another(lots of heat from reactions).

How do terrestrial and giant planets differ? List as many ways as you can think of

Giants- No hard surface (lots of gas), larger, less dense, farther from sun, outter layer is nitrogen and helium Terrestrial- Hard surface, smaller, more dense, close to sun.

Give brief descriptions of both the Kuiper belt and the Oort cloud.

I dont really understand this but here is a copy paste answer from another quizlet i found The Kuiper belt is a disk-shaped region of space beyond the orbit of Neptune that is dynamically stable. It is the source of short-period comets. The Oort cloud is much farther out than the Kuiper belt. It is a spherical region surrounding the Sun out to near 50,000 AU. This is the source of newly discovered long-period comets.

the smallest planet in the solar system

Mercury (to remember this think elements, mercury is the only planet named after an element and elements are tiny)

In what ways are meteorites different from meteors? What is the probable origin of each?

Meteorites are when a meteoroid makes contact with earth. Meteors are when a meteoroid comes into earths atmosphere. Meteors are mostly from comets that have had most of their ice body vaporized away (so they are smaller and less likely to make contact with earths surface because it gets burnt up faster. Meteorites are mostly from astroids or stuff from objects hitting mars or the moon

Venus rotates backward and Uranus and Pluto spin about an axis tipped nearly on its side. Based on what you learned about the motion of small bodies in the solar system and the surfaces of the planets, what might be the cause of these strange rotations?

Most likely from previous collisions with larger bodies

What is, by far, the most abundant component of Earth's atmosphere?

NITROGEN not oxygen

Which is the least dense planet?

Saturn(it is just gas and could literally float in a bathtub of water its crazy)

What does a planet need in order to retain an atmosphere?

Size mostly determine a planets ability to retain an atmosphere. A larger planet has a stronger gravitational force. If the gravity force is too weak, molecules of gas can escape (and a planet cannot retain molecules like Oxygen in order to create the atmosphere). Temperature also plays a role in this. Example, if a planet was too cold, nitrogen could only exist as a liquid and not as a gas (most of earths atmosphere)

Give a brief description of the asteroid belt.

Space between mars and jupiter that surrounds the sun which contains lots of rock

Briefly describe the greenhouse effect.

Sunlight is able to get through the atmosphere on the way in because the molecules are hotter(which mean have more energy) when it reaches the immediate layer of the atmosphere. Greenhouse gases are mostly man made which cause heat from the sun to be stuck in the atmosphere and in turn heat up the planet.

Frozen water exists on the lunar surface primarily in which location? Why?

The frozen water is mostly in deep craters on the south pole that are mostly on the dark side. Dark side never faces the sun so its very cold

Which type of planets have the most moons? Where did these moons likely originate?

The giant planets like jupiter and saturn. This is because they have greater gravitational pull that were able to capture smaller bodies during the formation of the solar system. (when big rocks were moving everywhere and crashing into stuff)

Why is Mars red?

The surface contains alot of iron oxide which is red (think rust) and winds on mars blow it everywhere

Why are asteroids and comets important to our understanding of solar system history?

They contain material from when the universe was formed unlike larger bodies that have undergone transformation processes

the moon with the thickest atmosphere

Titan (it orbits saturn)

Explain mountain building

When tectonic plates move toward each other one pushes over top the other which creates mountains (imagine 2 cars crashing into one another where one ends up on top the other)

How are comets related to meteor showers?

comets result in material being ejected or vaporized off of its body and it leaves like a trail of stuff behind which become meteors. If earth is near its path they are pulled towards earth and come into the atmosphere