Fear and Dread Trivia Quiz

Answer: Asaph Hall

The discoveries were made nearly a week apart on August 12th and 18th at the US Naval Observatory in Washington, DC. Asaph Hall thought he had seen a moon on August 10th, but could not confirm it because of bad weather, delaying the official discovery until the 12th. While showing his new discovery to a colleague late on the 17th into the 18th, Hall discovered a second moon.

The names Phobos and Deimos came from Book XV of Homer's "Iliad".

Answer: True

Despite being the smaller of the two Martian moons, Deimos, by virtue of being further away from the planet, was spotted first. The telescope used to discover the moons was a 26-inch (66 cm) refractor.

Answer: 30.35 hours

With the Martian day lasting 24.7 hours and Deimos' orbital period a slightly higher 30.35 hours, there is actually a lapse of 2.7 days between when the sun sets and rises again (for an observer on the surface of Mars).

Seen from Mars, a Deimosian full moon would be about as bright as Venus as seen from Earth.

Answer: Swift and Voltaire

In the early 17th century Johannes Kepler reasoned that Mars must have two moons, considering that Earth had one and Jupiter had four (known). Perhaps that is why Jonathan Swift referred to two moons orbiting Mars in his "Gulliver's Travels" (1726). A few years later, Voltaire (François-Marie Arouet) wrote of two Martian moons in his 1752 short science fiction story "Micromégas".

Answer: 1000

To be a bit more precise, the volume of Deimos is 999.78 km3. That makes it nearly 1/6th the size of Phobos. And a far cry from the size of our own Moon, which has a volume of 2.1958 × 10^10 km3.

Answer: True

Phobos and Deimos both orbit Mars in the same direction, but from the surface of Mars it looks as if they are going in opposite directions. The reason for this is that Phobos orbits the planet faster than it (the planet) rotates. Phobos' orbital period is a mere 7.66 hours!

Answer: The discoverer's wife

Astronomer Asaph Hall named the crater for his wife, Angeline Stickney Hall. Stickney was Angeline's maiden name. According to the Wikipedia page on Angeline Stickney, she was instrumental in encouraging Asaph to continue his efforts to find moons around Mars, when he was ready to give up.

There are a number of other named features on the surface of Phobos, most of them named for astronomers who studied Phobos and for characters and places in Jonathan Swift's "Gulliver's Travels".

Answer: True

At a distance of a mere 9,380 km, looking at Mars from the surface of Phobos would make it seem 6,400 times bigger than our Moon looks like from Earth. From the other direction, Phobos is not quite big enough to provide a full solar eclipse, despite its close proximity to the planet.

Answer: Tidal deceleration

Tidal deceleration means that the tidal bulges raised by the moon on their planet lag behind the moon, and cause the moon to decelerate in its orbit. In the case of Phobos, the moon gets about one metre closer to the planet every year.

Phobos will hit its Roche limit (the closest it can get to the planet before being destroyed by gravitational forces) at a distance of 3,620 km.

Answer: 1971

The Mariner program launched ten spacecraft between 1962 and 1973 with the intent to fly by Mercury, Venus and Mars. Seven of the missions were successful.

Mariners 1 and 2 were intended for Venus, but Mariner 1 was destroyed on liftoff. Mariner 2 completed its flyby of Venus in late 1962.

Mariners 3 and 4 were destined for Mars, but Mariner 3 malfunctioned. Mariner 4 completed its flyby of Mars in 1965.

Mariner 5 also went to Venus, in 1967.

Mariners 6 and 7 were both sent to Mars, completing their flybys in 1969.

Mariners 8 and 9 were also intended for Mars, but Mariner 8 was destroyed. Mariner 9 became Mars' first artificial satellite in 1971.

Mariner 10 was launched in 1973 and flew past both Venus and Mercury in 1974.