Carl Sagan

Question 1

What did he focus on in his career?

Answer 1

The physical condition of planets.

And the atmosphere surrounding Venus.

Question 2

Atmosphere of Venus

Answer 2

Has an extremely high surface temperature because of it has a massive greenhouse effect.
Atmosphere is high in CO2

Question 3

Life on Venus

Answer 3

No life. It is too hot and dry.
However, 30 miles above the the surface, where there is a big cloud layer, it is cooler and closer to the temperature of the Earth’s surface, opening up the possibility of life not on Venus, but in its atmosphere.

Question 4

Mars

Answer 4

The cause of Martian wave of darkening–seasonal light changes–is due to massive dust storms that cover huge swaths of the planet.

Question 5

SETI

Answer 5

Demonstrated how the foundations of life, amino acids and nucleic acids, could be made by exposing a mixture of simple chemicals to ultraviolet radiation.

Question 6

Publications

Answer 6

Books, articles, and narrated Cosmos.

Question 7

Messages into Space

Answer 7

For any alien civilizations/other space travelers to know where Earth is, and how to contact.
Pioneer plaques and a voyager golden record.