Question 1

Phobos and Deimos are moons of which planet?

Accepted Answer

Phobos and Deimos are two small, irregularly shaped moons that orbit around the planet Mars.

Question 2

What were the results of the life-sciences experiments aboard the Viking landers?

Accepted Answer

The Viking landers' experiments showed strong reactions releasing oxygen, but these were later attributed to nonbiological chemical reactions in the Martian soil, not biological activity.

Question 3

What role has methane played in the search for life on Mars?

Accepted Answer

The answer of What role has methane played in the...

Question 4

Experiments carried out to detect life on another world were performed by the:

Accepted Answer

The Viking landers were specifically designed to search for signs of life on Mars. They carried out experiments to look for organic molecules, performed tests for metabolic processes, and analyzed the Martian soil and atmosphere. While the results of the experiments were inconclusive, the Viking missions remain the most comprehensive and dedicated efforts to search for extraterrestrial life to date.

Question 5

Our Moon raises tidal bulges on Earth and as a consequence is being pulled gradually away from Earth.Phobos raises tidal bulges on Mars and as a consequence is being pulled gradually toward Mars.Why this difference?

Accepted Answer

Phobos orbits Mars faster than Mars rotates, causing tidal forces to pull it inward, unlike the Moon, which orbits Earth slower than Earth's rotation, causing it to move outward.

Question 6

Phobos orbits Mars in a prograde orbit with a period less than the rotational period of Mars itself.What consequence follows from this?

Accepted Answer

Phobos orbits Mars faster than Mars rotates, causing it to appear to rise in the west and set in the east.

Question 7

What evidence have some scientists claimed for ancient life on Mars (although the hypothesis has been strongly disputed by many other scientists)?

Accepted Answer

Some scientists have claimed that the Martian meteorite ALH84001 contains fossilized bacteria, although this hypothesis has been strongly disputed by many other scientists.

Question 8

Several components of the atmosphere and the environment on Mars render it sterile and antiseptic and would destroy life on the planet.Which component is NOT one of these factors?

Accepted Answer

Solar UV radiation (A), hydrogen peroxide in the soil (C), and ozone in the atmosphere produced by solar UV light (D) are all factors that contribute to the sterilization of the Martian environment. However, sulfuric acid droplets in the atmosphere (B) are not one of these factors. While sulfuric acid is a highly corrosive and harmful substance, it is not a factor that would directly destroy life on the planet.

Question 9

The unstable chemicals dissolved in the Martian regolith suggest that the amount of ultraviolet radiation reaching the surface of Mars is much greater than the amount reaching the surface of Earth.The Martian atmosphere lacks which constituent in sufficient quantities to absorb incoming ultraviolet radiation?

Accepted Answer

Ozone in Earth's atmosphere absorbs most of the incoming ultraviolet radiation. However, the Martian atmosphere lacks sufficient amounts of ozone to absorb the incoming ultraviolet radiation, making the surface of Mars more exposed to it.

Question 10

Where have some scientists hypothesized that they have found direct evidence for life,either contemporary or ancient,beyond Earth (although the hypothesis has been strongly disputed by many other scientists)?

Accepted Answer

Scientists have hypothesized that they have found direct evidence for ancient life beyond Earth in a meteorite composed of ancient Martian rock. This hypothesis, known as the "Martian meteorite" or "ALH84001" hypothesis, is controversial and disputed by many other scientists.

Question 11

A global magnetic field generated from inside the planet is found around which terrestrial planet or planets?

Accepted Answer

Mercury and Earth are the only terrestrial planets in our solar system that have a global magnetic field generated from their interiors. Venus and Mars do not have a global magnetic field; Venus has a very weak one induced by the solar wind, and Mars only has remnant magnetism in certain areas of its crust.

Question 12

Which craters are the youngest?

Accepted Answer

The answer of Which craters are the youngest?
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Question 13

On which planet have experiments been carried out to search for life-forms or evidence of life?

Accepted Answer

Experiments have been carried out on Mars to search for life-forms or evidence of life.

Question 14

According to modern dynamo theory,the production of a planetwide magnetic field around a terrestrial-type planet appears to require:

Accepted Answer

Modern dynamo theory suggests that a planetwide magnetic field is generated by the movement of a conductive fluid, typically in a molten metallic core, combined with the planet's rapid rotation. This movement and rotation create a dynamo effect that produces the magnetic field. A permanently magnetized solid core (option B) does not align with the dynamo theory's mechanism for generating a magnetic field.

Question 15

The Martian moon Phobos orbits near the equatorial plane of Mars in just over 7.5 hours in the same direction as the planet rotation.How then would you see Phobos move across the Martian sky from the surface of the planet?

Accepted Answer

Phobos orbits in the same direction as the planet rotation, which means it rises in the west, moves rapidly across the sky, and sets in the east. Its orbital period is just over 7.5 hours, so it would appear several times per Martian day. Choice A is incorrect because Phobos' orbit is too fast for it to appear only once per Martian day. Choice B is also incorrect because Phobos' orbital period is too short for it to appear several times per Martian day. Choice C is incorrect because Phobos' orbit is not quite synchronous with Mars's rotation period.

Question 16

If we characterize the age of a planetary surface by the age of the oldest feature that has been dated there,then the ages of the surfaces,from youngest to oldest,are:

Accepted Answer

Venus has the youngest surface, followed by Earth, and then the Moon.

Question 17

The exploratory life-sciences experiments aboard the Viking spacecraft landers found evidence of:

Accepted Answer

The exploratory life-sciences experiments aboard the Viking spacecraft landers found evidence of very reactive chemistry in the Martian surface rocks, but no evidence of life or remnants of life-forms. This suggests that there may have been no life on Mars or any remnants of past life that could be detected with the instruments available at the time.

Question 18

When were the two moons of Mars,Phobos and Deimos,discovered?

Accepted Answer

Phobos and Deimos were discovered by American astronomer Asaph Hall in 1877. Option A is the year when Neptune was discovered, option B is the year when Galileo discovered the four largest moons of Jupiter, and option D is the year when Pluto was discovered.

Question 19

The moons of Mars are:

Accepted Answer

The description fits the characteristics of the moons of Mars, known as Phobos and Deimos, which are irregularly shaped, heavily cratered, and have grooves on their surfaces.

Question 20

The shapes and sizes of the two moons of Mars are:

Accepted Answer

The two moons of Mars, Phobos and Deimos, are irregular in shape and very small, with diameters of about 22.4 km and 12.4 km, respectively.

Quiz 6: The Terrestrial Planets and Their Moons