Planets
Describe the differences between terrestrial and jovian planets
- Terrestrial planets are inner, they are rockier and denser.
- Jovian planets are outer, they are gas giants with low densities. They are colder and are made of hydrogen, helium, and ices.
A. What are granules on the surface of the sun?
B. What causes granules to appear to be different colors?
A. When looking at the sun it appears textured. Darker reds spots (versus white and yellow) are all indicative of gas bubbles churning and cooling off. Gas bubbles churning and being replaced constantly (the size of Texas) are granules.
B. The brighter the granule the hotter it is. Different colors are based on temperature, and they only last 10-20 minutes before cooling.
What are some typical characteristics of a star?
All objects emit and absorb radiation, planets reflect light, but stars are black body radiators, they absorb all the electromagnetic radiation that strikes it
Gives off the max amount of radiation at that temperature
How was the moon formed?
Giant Impact Hypothesis
During the formation of the solar system a body impacted the earth, the impact liquified earths surface and ejected material, this material orbited Earth and combined to form th moon, moon is the same age as earth basically
Nebular hypothesis
We evolved from a solar nebula (an enormous rotating cloud of mostly hydrogen and helium)
It contracts gravitationally and as they contract they spin faster
Collisions of matter created the planets 4.6 billion years ago
Planet is also created protoplantes as they collided
These collisions caused protoplanets to become larger and form planets and moons
Which planets are Terrestrial? Jovian?
Terrestrial: Mercury, Venus, Earth, Mars.
Jovian: Jupiter, Saturn, Uranus, Neptune.
A. How does a photon reach the Earth?
B. How can we view the layers of the sun’s atmosphere?
A. It is produced in the core of the sun during nuclear fusion, then it goes to the radiation zone where it gets stuck for a long time, then it goes to the convection zone and gets shot out away from the sun, then it takes minutes to get to the Earth.
B. You need a solar eclipse to block the photosphere of the sun so that you can see what’s around it.
Be able to describe the relationship between color, temperature, and radiation wavelength of a star.
Very hot stars emit most energy in the form of short-wavelength light- appear blue
Cooler stars emit most energy in teh form of longer wavelength light- appear red
Stars with moderate temps appear yellow
What is the difference between a revolution and a rotation? What is significant about the moon’s rotation and revolution?
The moons rotation around its axis and its revolution around Earth are both 23.7 days. Because of this, the same side of the moon always faces Earth.
What forces are constantly working on a star?
Gravity pushes down and nuclear fusion pressure pushes out.
Explain why scientists believe there is water on Mars
Pressure and temperature of Mars is too low for water to exist as a liquid. However, we have evidence that liquid water does flow in the form of a brine. A lot of surface features showing dried up river beds and erosion, and possible floodplains. Most water is trapped in polar icecaps and within the soil as permafrost.
A. What is solar wind?
B. What is a sunspot?
C. Why do sunspots occur?
D. What is a solar flare? A CME? Difference?
A. Charged particles escaping the suns gravitational pull/ leaving. These make cosmic space radiation.
B. Temporary-caused by magnetic interference Convection is not productive in these areas (They are cooler and darker than surrounding areas)
C. They are caused by magnetic interference. Usually above a sunspot is a corno al loop which is an arc of matter and energy resulting from a twisted magnetic force, they usually have a base of a sun spot. They can be eruptive or quiescent
D.
- A solar flare is released around one sunspot
- A CME is a collection of sunspots all releasing material. - The difference is how large of a charged particle is released.
A. What are the typical stages of a moderately sized star during its life cycle?
B. How long is a star usually in the main sequence? What does it depend on?
A. Our sun. Starts as a stellar nebula, then gas heats up and it becomes a protostar, goes to the main sequence, once it has used up its hydrogen fuel it collapses and expands into a red giant, dispels all outer gasses as a planetary nebula, becomes a white dwarf. How long it stays in the main sequence is dependent on its temperature. Hotter stars are shorter periods of time in the main sequence. Then it will become a black dwarf.
B. 90% of its life. Age at different rates depends on temperature. Yellow stars typically burn for 10 billion years
What is the difference between a sidereal and synodic month?
Sidereal is real. It aligns with a distant star. Or it’s every 27.3 days. Because the Earth is also orbiting, the moon has to go slightly further to get between earth and sun so slightly longer is synodic. 29.5 days. Motion is counter clockwise.
Compare meteoroids, meteors, and meteorites
Meteoroids= small solid particles moving through space
Ex: Russia Meteorite
Widespread glass damage after the impact, wasn’t the impact that caused the damage
Meteor= “shooting star” streak of light as meteoroid enters Earth;s atmosphere and burn up
Size of grains and vaporize before touching Earth’s surface
Meteorite= meteoroid that reaches Earth’s surface
(Anything in a museum)
Heavy because they are made of iron and nickel.
Which planet has a hexagon shaped storm on the North Pole?
Saturn
Describe the process of nuclear fusion in the sun
Happens from two main things: need to have enough mass because the center is extremely dense, and it needs to be extremely hot so that particles are packed and moving fast and slamming into each other. 4 hydrogen produce a helium, 4 hydrogen collide and a photon (an energy/light packet) is released as it turns into helium.
A. What is the H-R Diagram?
B. What are the labels for the x and y axis on the H-R Diagram
C. How is brightness related to temperature and size?
A. A system of classifying stars and understanding their evolution.
B.
X axis is the surface temperature of a star, and it decreases
Y axis is the luminosity of a star and increases
C. Bigger hotter stars are brighter.
What is the umbra and penumbra?
Within a solar eclipse there is a more concentrated smaller darker shadow on earth and a more gradual one, the umbra is the more concentrated and the penumbra is shadowed which one the Earth is in is if its a partial or full eclipse.
Umbra= part of the Earth in the dark shadow. They will see a total solar eclipse.
Penumbra= part of the Earth in the lighter shadow. They will see a partial solar eclipse.
Understand rotation, revolution, precession, and eccentricity
Rotation around axis (1 day), revolution around Earth (1 year).
Eccentricity is the amount an orbit deviates from its circular shape, a larger number means a less circular orbit
Give a brief description of each (composition, atmosphere, temperature, and other unique features):
Inner:
Mercury is the closest to the sun, and has barely any atmosphere because it is too hot for gases. It has drastic difference in night and day temperatures because of its slow rotation, and a lot of impact craters.
Venus, second planet from the sun. Venus is the hottest planet in the solar system because of its atmosphere. Mainly made out of CO2 creating a green house gas effect. It is almost the same size, mass, and density of earth= earth’s twin.
Earth, third from the sun, we have liquid water due to unique atmosphere and distance from the sun along with water in all three states= Goldilocks planet, and life and all sorts of weather
Mars, fourth. We have evidence of water, its red and we have invidente of ice caps of brine. It’s tilted and has weather like earth. It has a unique color from iron. 50% father from the sun than earth, jump in space before and after.
Outer planets: (they all have rings made up of broken moons)
Jupiter, fifth planet, largest, many moons, Much like the sun but not massive enough to be a star.
Saturn, sixth planet, rings, very cold, also has many moons, least dense in the solar system (will float in a bathtub), hexagon shaped storm on North Pole
Uranus, seventh, is tilted to laying down
Neptune, eight planet, windy and cold and is the furthest out planet, upper atmosphere has frozen methane clouds.
Describe the layers of the sun: Photosphere Chromosphere Corona Core Radiation Zone Convection Zone
Photopsphere is the visible surface
Appears grainy due to granules
-each are the size of Texas
-only last 10-20 minutes before cooling
-brightness comes from hot gases rising
Chromosphere, chrome=color has a reddish tint
-thin layer of gases
-can observe during a solar eclipse
-red rim around the sun
Corona
-outermost layer
-visible only when the photosphere is covered
-Extenders a million km from surface
-Outer fringe of corona, gases have speed great enough to escape the pull of the sun is solar wind
Core
Region where energy is produced from fusion
Radiative zone
Particles of light (photons) carry energy
Takes thousands of years for a photon to move to the next layer
Convection Zone
The motion of gases in the sun transfers energy outwards
-gas in this layer mixes and bubbles
-bubbling effect is seen as granulation on the surface
A. Describe the red giant stage
B. What are the three possible end results for a star and relate this to its starting mass
A.
Hydrogen in the core is used up. Gravity takes hold since th nuclear pressure in the core is no longer supported, the star o collapses down for a moment into a really small volume, it converts a ton of energy into thermal energy which really heats up teh sun, triggering nuclear fusion in the outer layer of the sun, the hotter gasses heated and so they expand outwards, teh outermost layers then cool since they are really far away from the sun, the center is hotter then ever but the outer layers have cooled from expansion.
B.
Low mass starts end as white dwarves. Medium mass stars end as red giants then white dwarves. White dwarves then fade to black dwarves. High mass stars can end as supernovas then become either neutron stars or if really massive then black holes,
Know the difference between a lunar and solar eclipse.
Solar eclipse: New moon. Earth-moon-sun.
Lunar Eclipse: Full moon (moon-Earth-sun) Moon appears red due to Earth emitting long wavelength (red) radiation to th moon which bounces back at us.
Supermoon= when the full moon appears when it is in pedigree/ closest to the Earth within its orbit.
What are the three main types of galaxies? Compare the ages of the stars in each type
Spiral galaxies
-young and old stars, oldest in the arms
-barred spirals rotate as a rigid system
-greater concentrations of stars near center
-30% are spirals
Elliptical galaxies
-old stars
-60% are elliptical
-Range in shape from round to oval
-largest galaxies are elliptical
Irregular galaxies
-young stars
-10% are irregular galaxies
-Large and Small Clouds