St. Joseph Astronomy Olympiad 2015 (senior) 414x2v

ANNUAL SCIENCE FESTIVAL 2015 ST. JOSEPH HIGHER SECONDARY SCHOOL

ASTRONOMY OLYMPIAD (Class 11-12) Total Mark: 50 (MCQ 40, Math 10) 1. Which planets rotate on its axis from east to west? a. Jupiter & Venus b. Venus & Mercury c. Uranus & Neptune d. Venus & Uranus 2. The minimum distance between the sun and the earth occurs on a. December 22 b. June 21 c. January 3 d. September 22 3. When the sun is nearest to the earth, the earth is said to be in a. Aphelion b. Perihelion c. Apogee d. Perigee 4. How much of the surface of the moon is visible from the earth a. About 59% b. More than 75% c. Only about 40% d. Only about 25% 5. On the surface of the moon the a. Mass and weight become less b. Only the mass is less c. Mass remain constant and only the weight is less d. Mass and weight both remain unchanged

Time: 30 Minutes 6. When a superior planet is at opposition it is making an angle of how many degrees with the sun? a. 0 degrees b. 45 degrees c. 90 degrees d. 180 degrees 7. A Galactic year is the length of time that it takes our sun to orbit the galaxy. In Earth years, how long is a Galactic year? a. 100 million years b. 230 million years c. 620 million years d. 940 million years 8. The habitable zone around a star is _____? a. The region around a star where liquid water can exist on planetary surfaces b. The region around a star where life exists c. The region around a star where humans can survive d. The region around a star where rocky planets form e. The region around a star where the ultraviolet radiation does not destroy organisms on a planetary surface 9. How are galaxies important to our existence? a. Without galaxies, the universe could not be expanding b. Without galaxies, there could not have been a Big Bang c. Galaxies Prevent planets from leaving their orbits around stars; e.g. our galaxy prevents the earth from leaving its orbits of the Sun d. Galaxies recycle heavy elements produced in stars into future generations of stars

ANNUAL SCIENCE FESTIVAL 2015 ST. JOSEPH HIGHER SECONDARY SCHOOL 10. Who discovered that Jupiter has moons? a. Aristotle b. Ptolemy c. Kepler d. Galileo e. Tycho Brahe 11. From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 486.1 nanometers (nm). The spectrum of a particular star has the same hydrogen line appearing at a wavelength of 485.9nm. What can we conclude? a. The star is getting hotter. b. The star is getting colder. c. The "star" actually is a planet. d. The star is moving toward us. e. The star is moving away from us. 12. Which planet has the highest average surface temperature and why? a. Mercury, because it is closest to the Sun b. Mercury, because of its dense carbon dioxide atmosphere c. Venus, because of its dense carbon dioxide atmosphere d. Mars, because of its red color e. Jupiter, because it is so big 13. Which two properties are most important in determining the surface temperature of a planet? a. Size and distance from the Sun b. Internal temperature and atmosphere c. Size and chemical composition d. Distance from the sun and atmosphere e. Size and atmosphere 14. Which of the following statements about the sunspot cycle is not true? a. The number of sunspots peaks approximately every 11 years. b. With each subsequent peak in the number of sunspots, the magnetic polarity of the Sun is the reverse of the previous peak. c. The rate of nuclear fusion in the Sun peaks about every 11 years.

d.

e.

The cycle is truly a cycle of magnetic activity, and variations in the number of sunspots are only one manifestation of the cycle. The number of solar flares peaks about every 11 years.

15. On a Hertzsprung-Russell diagram, where on the main sequence would we find stars that have the greatest mass? a. Lower right b. Upper right c. Upper left d. Lower left e. None of the above 16. Sirius is a spectral type A star whereas Rigel is a spectral type B star. What can we conclude? a. Sirius has a higher core temperature than Rigel. b. Rigel has a higher surface temperature than Sirius. c. Sirius has a higher surface temperature than Rigel. d. Rigel has a higher core temperature than Sirius. e. Sirius and Rigel have the same temperature 17. Space within clusters of galaxies is not expanding because ____________? 1. Expansion of the universe affects only empty space, not space in which matter is present. 2. The universe is not old enough yet for these objects to have begun their expansion. 3. Space IS expanding within clusters of galaxies, which is why clusters tend to grow in size with time. 4. Their gravity is strong enough to hold them together even while the universe as a whole expands. 5. There is not enough matter in the clusters to repel the galaxies away

ANNUAL SCIENCE FESTIVAL 2015 ST. JOSEPH HIGHER SECONDARY SCHOOL 18. What does the Schwarzschild radius of a black hole depend on? a. Whether the black hole formed in a massive-star supernova or in some other way b. The radius of the black hole, as measured by careful observations of its size c. Both the mass and the chemical composition of the black hole d. Only the mass of the black hole e. The colour of the black hole

Short Question

19. Which of the following places is not generally considered a potential home for life in our solar system? a. Jupiter's atmosphere b. Europa c. Mars d. Ganymede e. All of the above

ANSWER

20. We do not expect to find life on planets orbiting high-mass stars because? a. Planets cannot have stable orbits around high-mass stars. b. The stars are too hot to allow for life. c. The lifetime of a high-mass star is too short. d. The high-mass stars emit too much ultraviolet radiation. e. They emit too much ultraviolet radiation

5×2=10

I.

Spectroscopic measurements using the neutral Sodium line with wavelength 592nm find that in the spectrum of Kapteyn's star this line appears at a wavelength of 592.48nm. Find the radial velocity of Kapteyn's star. Note that this is a positive number if the star is receding from Earth,and a negative number if it is approaching Earth. Express your answer in km/s.

II.

If the angular diameter of the Moon is 31', then what is the diameter of its image with an objective of focal length 254 cm? ANSWER