Quiz 7 (April 18-24, 2005): Astronomy
Quiz 7 (April 18-24, 2005): Astronomy

1. A white dwarf is an astronomical object which is produced when a low to medium mass star dies. What is the term used to define the maximum mass of a white dwarf? It is approximately 3 × 10³⁰ kg, close to 1.44 times the mass of the Sun and named after a Nobel Prize winning astrophysicist from India.

2. Which American astrophysicist discovered the velocity-distance relation, which led to the concept of the expanding universe? The law states that the greater the distance between any two galaxies, the greater their relative speed of separation. He is also generally credited for discovering the redshift of galaxies and has a very well known telescope named after him.

3. Name this largest moon of Saturn - discovered by the Dutch astronomer Christiaan Huygens, it is the second largest moon in our solar system and is the only one to have a dense atmosphere consisting of more than trace gases. Its atmosphere is denser than Earth's, with a surface pressure more than one and a half times that of our planet and supports an opaque cloud layer that obscures its surface features. The 'Huygens probe' from the Cassini-Huygens mission reached its surface on January 14, 2005 by an atmospheric descent and relayed scientific information.

4. Which American astronomer, famous for his efforts to popularize science wrote the bestselling novel 'Contact', which was later made into the 1997 movie of the same name, starring Jodie Foster and Matthew McConaughey?

5. Which planet in our solar system has two moons Phobos and Deimos, both of which are small and odd-shaped, with the hypothesis that they are probably captured asteroids? It is named after the Roman god of war and has only a quarter the surface area of the Earth and only one-tenth the mass, though its surface area is approximately equal to that of the Earth's dry land because it lacks oceans.

6. What is the so-called boundary of a black hole referred to as? It is defined as the boundary in spacetime for a given observer beyond which no electromagnetic energy, including light, can reach the observer. It is also the title of a science fiction movie starring Lawrence Fishburne and Sam Neill about a spaceship that had disappeared seven years ago (the spaceship has the same name as the movie).

7. Which Indian astronomer (~ 500 AD) presented a mathematical system that described the earth as spinning on its axis and considered the motions of the planets with respect to the sun (a heliocentric solar system)? He also gave a very accurate estimation of 'pi'. India's first satellite (launched in 1975) was named after him.

8. Foundations of modern astronomy
a. Which ancient Greek astronomer was responsible for the 'geocentric' model of the solar system (i.e. earth is the center of the solar system, and all planets revolve around the sun). This remained the generally accepted model in the Western and Arab worlds until it was superseded by the heliocentric solar system.

b. Which brings us to the next question - who was responsible for the 'heliocentric' model (sun at the center) of the solar system (as seen earlier, it was not new, but it is generally attributed to him in the modern age). He hails from Poland and this discovery is considered to mark the beginning of modern astronomy.

c. Contributing to modern astronomy were the three laws of planetary motion, the first of which states that the planets move not in circular but elliptical orbits around the sun (To be exact 'The orbit of a planet about a star is an ellipse with the star at one focus.'). Who was the German astronomer who proposed these laws?

9. Next to the sun, which is the star nearest to the earth? It is a red dwarf in the Alpha Centauri star system and is roughly 4.22 light years from Earth.

10. Which was the first planet in our solar system to be discovered that was not known in ancient times? It had been observed on many previous occasions but was always dismissed as simply another star. It was eventually discovered by Sir William Herschel in 1781.

11. What was the name given to a small planet supposed to exist in an orbit between Mercury and the Sun (from a 19th century hypothesis that has now been superseded by Albert Einstein's theory of general relativity)? [HINT: the name is the same as that of the planet from which Star Trek's Spock came from]

12. Alnitak, Alnilam and Mintaka (zeta, epsilon and delta - i cant seem to be able use greek symbols!) are three very prominent stars in the night sky and are signature identifiers for which constellation? They are visible throughout the world, make this constellation universally recognized. [HINT - they form the 'belt']
- posted by Aditya @ 9:02 AM