Midterm 1 - Quiz 6

The correct answer is "about the temperature of melting lead on Earth." This means that the typical "mid-day" high temperatures at Mercury's equator are extremely hot, similar to the temperature at which lead melts on Earth. This suggests that the temperatures on Mercury can reach extremely high levels, making it much hotter than Earth.

The orbit of Mercury is such that its angular distance from the Sun is never more than 28 degrees. This means that Mercury is always relatively close to the Sun in the sky and is often obscured by the Sun's glare. However, during the 1 to 2 hours just after sunset or just before sunrise, when the Sun is below the horizon but its light still illuminates the sky, Mercury can be seen in the twilight. This is why it is generally visible during these specific times.

The sun's intensity is about 7x that on Earth according to Energy/Surface Area.

Mercury's rotation axis being almost perfectly perpendicular to the plane of its orbit means that the planet does not experience significant tilting or changes in its orientation relative to the Sun throughout its orbit. This lack of tilt results in minimal variations in solar radiation and temperature across different regions of the planet, leading to very little seasonal differences. Therefore, the correct answer is that Mercury's seasons are almost non-existent, with much less seasonal differences compared to Earth.

Mercury has a magnetic field that is only about 1% of the magnetic field of the Earth. This means that the strength of Mercury's magnetic field is much weaker compared to Earth's magnetic field.

The correct answer is 2/3 of Mercury's revolution period around the Sun (58.67 days). Tidal locking is a phenomenon where the gravitational forces between two celestial bodies cause one body to always face the other with the same side. In the case of Mercury, its rotation period on its axis is 2/3 of its revolution period around the Sun. This means that it takes Mercury 58.67 days to rotate once on its axis while it takes 88.0 days for it to complete one revolution around the Sun.

Mercury has almost no atmosphere, which means there is very little air or gases surrounding the planet. The low escape speed of Mercury makes it difficult for any atmosphere to "stick" to the planet, as the gases can easily escape into space. Additionally, the heat of mid-day on Mercury is extremely high, causing the atmosphere to "boil away" and evaporate. Therefore, all of the given options explain why it would be difficult to breathe on Mercury.

Ex. Caloris Basin (Mercury) Orientale Basin (Moon)

The surface of Mercury is similar to our Moon in several ways. It is less heavily cratered than the Moon, meaning it has fewer impact craters. Additionally, Mercury has light-colored extensive "inter-crater plains" instead of dark-colored "maria" like the Moon. These inter-crater plains cover large areas of Mercury's surface. Furthermore, Mercury has numerous ridges, known as "scarps," in its crust. These scarps are thought to be the result of the planet's surface shrinking as its core cools. Therefore, all of the given options accurately describe the surface of Mercury.

Mercury's poles experience extremely cold temperatures due to their lack of sunlight and their distance from the sun. The temperature of liquifying nitrogen on Earth is around -346 degrees Fahrenheit (-210 degrees Celsius), which is extremely cold. Therefore, if the typical "midnight" low temperatures on Mercury's poles are somewhat warmer than this temperature, it means that they are still very cold but not as cold as liquifying nitrogen on Earth.

Mercury is believed to have become geologically inactive, or "dead," around 4 billion years ago. This estimation is based on the age of craters on its surface, which are similar to those found on the Moon. The lack of geological activity suggests that Mercury's internal heat source had depleted, causing its surface to cool and solidify. Therefore, the correct answer is 4 billion years using cratering age estimates as for our Moon.

The statement "none of the above" suggests that the evidence for plate tectonics on Mercury does not include any of the listed options, namely complex craters, basins, highlands, or plains. This implies that there must be other forms of evidence that support the existence of plate tectonics on Mercury, which are not mentioned in the given options.

Tidal locking refers to a phenomenon where the rotation period of a celestial body matches its orbital period, causing one side to always face the other. However, tidal locking does not directly affect the occurrence of ocean tides. Ocean tides on Mercury would still occur more than once per day, just like on Earth, due to the gravitational forces exerted by the Sun and other planets. Therefore, the correct answer is none of the above.