L2
讲座
1. What does the class mainly discuss?
How sulfuric acid affects atmospheric temperatures
How space probes have contributed to the study of Venus’ atmosphere
Why Venus’ lower atmosphere is so hot
Why Venus is considered Earth’s sister planet
2. Before the 1970s, why did astronomers believe that Venus’ surface temperature would prove to be similar to Earth’s?
They thought that the atmospheres of the two planets were chemically similar.
They knew that most of the sunlight reaching Venus’ atmosphere is reflected.
They calculated that the surface areas of Venus and Earth are similar.
They assumed that day and night are roughly the same on Venus as they are on Earth.
3. What do present-day Venus and Earth have in common?
They both have oceans of liquid water.
They both have volcanoes that produce carbon dioxide.
They both have atmospheres with a high proportion of greenhouse gases.
They have atmospheres containing similar amounts of sulfuric acid.
4. According to the professor, why could oceans exist on Venus shortly after it first formed?
Surface temperature variations were greater at that time.
Water vapor condensed after mixing with carbon dioxide.
There was much less volcanic activity at that time.
The Sun’s energy output was much lower at that time.
5. According to the professor, why has Earth’s temperature remained relatively constant?
Its clouds prevent too much heat from escaping
Its oceans absorb large quantities of carbon dioxide.
Almost no sulfuric acid is produced by its volcanoes.
Heat loss in its polar regions balances heat from the Sun.
6. Why does the professor say this:
To provide information students will need for making calculations
To explain the cause of one of Venus’ unusual features
To add emphasis to the point he has been making
To confirm one of the conclusions made by astronomers before the 1970s
