Test your basic knowledge |

DSST Astronomy

Subjects : dsst, science
Instructions:
  • Answer 42 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. A narrow - bright region of the spectrum - produced when electrons in atoms jump from one energy level to a lower energy level.






2. Type of active galaxy whose emissions come from a very small region within the nucleus of an otherwise normal-looking spiral system.






3. Stage in which a star has used up its helium and its outer layers escape into space - leaving behind a hot - dense core that contracts.






4. A shift in the lines of an object's spectrum toward the red end. It indicates that an object is moving away from the observer. The larger it is - the faster the object is moving.






5. An immense cloud of gas (mainly hydrogen) and dust in interstellar space.






6. Either of the two times of the year when the Sun is at its greatest distance from the celestial equator.






7. A rapidly rotating neutron star which emits radiation in magnetic pulses.






8. The name given to the four inner planets: Mercury - Venus - Earth - and Mars. Mercury and Venus lack moons.






9. Large - dense groupings of older stars held together by mutual gravitational attraction - which is what keeps them together longer than open clusters.






10. The period between successive new moons (29.531 days).






11. The most precise measurement of Earth's rotation time.






12. A type of pulsating variable star that changes brightness in a regular and predicable manner - making it a useful 'standard candle' for learning absolute magnitudes.






13. Also called nuclear bulge - this is a swelling at the center of spiral galaxies. Bulges consist of old stars and extend out a few thousand light-years from the galactic centers.






14. The apparent displacement of an object as seen from two different points that are not on a line with the object.






15. Energy that is radiated or transmitted in the form of rays or waves or particles.






16. 'Failed' star; a star not massive enough to sustain nuclear fusion.






17. The portion of the Milky Way in which our solar system resides.






18. A relatively small extraterrestrial body consisting of a frozen mass that travels around the Sun in a highly elliptical orbit.






19. 1. If no forces act on a body - its speed and direction of motion stay constant (an object in motion stays in motion - an object at rest stays at rest). 2. Force=mass x acceleration (F=ma). 3. When two bodies interact - they exert equal and opposite


20. Polish astronomer who produced a workable heliocentric model of the solar system.






21. Either of the two celestial points at which the celestial equator intersects the ecliptic plane.






22. A cluster of stars (or a small constellation).






23. The small - dense remains of a high-mass star after a supernova.






24. Areas on the sun's surface that are cooler and less bright than surrounding areas - are caused by the sun's magnetic field - and occur in cycles.






25. Depressions that form when a volcano collapses - as opposed to craters formed by meteoroid impact.






26. A change in the apparent frequency of a wave - as observer and source move toward or away from each other.






27. A streak of light in the night sky that results when a meteoroid hits the earth's atmosphere - and air friction causes the meteoroid to melt or vaporize or explode.






28. Large - hot - bright star late in the main sequence - having exhausted its hydrogen fuel. Its name comes from its color and size.






29. Italian astronomer and mathematician who was the first to use a telescope to study the stars.






30. The large - outer planets made of gas - Jupiter - Saturn - Uranus - & Neptune. These all have large moons and rings.






31. Arrangement of electromagnetic radiation--including radio waves - visible light - gamma rays - X-rays - ultraviolet waves - infrared waves - and microwaves--according to their wavelengths.






32. The older - redder stars that populate a galaxy's hale and bulge. Low metallicity.






33. Short for 'quasi-stellar radio source -' a bright - point-like object that produces the luminosity of 100 to 1 -000 galaxies within a region the size of a solar system.






34. The plane of the Earth's orbit around the Sun.






35. The dark lines in a spectrum where light of particular wavelengths has been absorbed.






36. The speed of light in meters per second. It is also 300 -000 kilometers per second and 186 -000 miles per second.






37. An orbit that is backward or contrary to the orbital direction of the other planets.






38. A pair of stars held together by their mutual gravity and in orbit about each other which can be seen with a telescope as separate objects.






39. The distance that light travels in one year; about 9.46 trillion kilometers.






40. The younger stars - some of which are blue - that populate a galaxy's disk - especially its spiral arms. High in heavy metals.






41. Very bright - often giant - elliptical galaxy type that emits as much or more energy in the form of radio wavelengths as it does wavelengths of visible light.






42. A star that expands and cools once it runs out of hydrogen fuel.