A8 Report

1 Formation of the Solar System Lab Report of Findings Name: __Dasol Lee______________ Date: ___10/30/2023________ Based on what astronomers have observed in our solar system, they have developed a theory of how the solar system formed. The theory is outlined in the pre-lab materials; refer to these if you have forgotten the basics. A good overview (including some thoughts on how a planet is defined!) is here: http://www.pbs.org/video/2365621408/ The observations below are some of the reasons the theory was developed and offer support for it. However, not all the bodies in the solar system "follow the rules". Your job in Part I is to sort solar system bodies based on whether or not they support the observations. If they seem to contradict the basic observations, it will be important to see if there might be reasons that can explain it, or whether it might be necessary to add features to the theory. Evaluate each one to see if it fits the current theory, or would need further explanation. Potential objects include (go to the website below): http://nssdc.gsfc.nasa.gov/planetary/factsheet/ Other fact sheets are also available from its parent site NSSDCA Planetary Home Page , and Wikipedia is a good source for most of basic facts organized by planetary object. And of course, search of the internet for specific aspects of planetary objects is also often fruitful, especially for comparative analysis. Part I: Making & Documenting Principal Observations Here are some of the observations that went into development the current theory of solar system formation. Fill in the table below with various solar system bodies (you won’t be able to do all of the moons for example, so choose ones that provide interesting and possibly contradictory data). Indicate whether they support or challenge the current theory, and in either case give an explanation in the final column. Earth is listed as an example.  Observation 1 – Most bodies in the solar system orbit the Sun (or in the case of Moons their planet) in the same direction (counter clockwise as see from the north pole of the Sun, above the plane of the orbits)  Observation 2 – Most of these bodies also move in the same plane (more or less), sort of like marbles rolling on a plate. For Moons you might expect them to move in their planet’s equatorial plane.  Observation 3 – Most solar system bodies also rotate on their own axes in the same direction (counter clockwise as seen from above the north pole of the Sun  Observation 4 - Small rocky planets and objects are closer to the Sun  Observation 5 – Larger gas giants and the small icy bodies lie outside the “frost line”

2 Solar system body Supported Not Applicable Explanation of observations that don’t fit this object Other observations or interesting facts  Include questions that the object raises for you. Earth All N/A N/A Earth’s density is higher than either Mercury's or Venus’ yet it apparently formed farther out? Why? Mercury All N/A N/A In the entire Solar System, Mercury is the closest to the Sun but it is not the hottest, why? Venus 1,2,4,5 3 Venus does not fit the description of Observation 3 because it rotates in retrograde motion, meaning it moves backwards or opposite to the other planets. Why does Venus rotate this way? In retrograde motion? Mars All N/A N/A How is Mars’ atmosphere thinner than Earth’s atmosphere? Jupiter All N/A N/A How is does Jupiter have the shortest days of all the eight planets? Even with its placement? Saturn All N/A N/A How does Saturn have such record breaking winds compared to any other planets? Uranus 1,2,4,5 3 Uranus does not fit the description of Observation 3 because it too rotates in retrograde motion. How does Uranus have so many rings that surround the planet and others don’t? Neptune All N/A N/A What makes Uranus so cold compared to all the other planets? Pluto 1,3,5 2,4 Pluto does not fit the description of Observation 2 because it is not on the same plane as the other 8 planets. Pluto does not fit the description of Observation 4 because it is technically a “small rocky planet” being made up of 70% rock but it is the furthest planet from the Sun. Could Pluto possible be a former moon of the planet Neptune?

4 2. Which of the objects raised significant questions? Come with an alternative explanation for each, what might have been different for this object without contradicting the nebular theory in general? a. I would definitely say that Venus raised significant questions for me. The other 3 terrestrial planets all support nebular theory besides Venus. So what makes Venus so special? Also why does Venus instead of moving in a prograde motion like most planets, move in a retrograde motion from East to West? Part III: Application 1. In light of what you saw in the first two parts, discuss an object you found that needs further explanation to account for its motion or characteristics in addition to the basic nebular theory. For example, Earth’s large moon is probably the result of a collision between Earth and another small planet early in solar system history. That would help explain why Earth’s density is a little higher than the other terrestrial planets, while the moon’s density is a little lower. a. I want to understand why the Toutatis is an observed asteroid and what makes it so special. The way it orbits is really weird and chaotic, what made it this way? 2. There has been talk recently of a Planet X in the Kuiper Belt that has so far not been observed but might be affecting the motion of other small planets beyond the orbit of Pluto. What if the Object X were observed and found to be moving in a highly eccentric orbit that is also in the opposite direction from the motion of the known solar system planets? Would this be a serious problem for the nebular theory or not. Explain in a paragraph or two. a. This would be a major problem for the nebular theory specifically for observations 2 and 3. Nebular theory ascertains that bodies orbit the sun on relatively the same plane. Basically, think about marbles rolling around a plate. However, if Object X is highly eccentric, this poses as a contradiction to that part of the nebular theory. Also, Object X moves in the opposite direction from the motion of the known solar system planet— essentially moving in a retrograde fashion. This, too, violates the nebular theory as most bodies will rotate on their axes in the same direction (counterclockwise). Since Object X is moving the opposite direction, this poses another problem for support of the nebular theory. 3. How would you expect the solar system and its bodies to be different if the frost line had been beyond the orbit of Jupiter? a. If the frostline were to be beyond the orbit of Jupiter, I believe that it would possibly allow more planets to be terrestrial instead of a dead frozen planet where nothing can live. 4. How would you expect the solar system and its bodies to be different if the gas and dust had persisted for much longer than we think it did in the solar system? a. If the gas and dust had persisted for much longer than we think it did, I think it would been that it would take our solar system way longer to form. (planets, stars, etc.)