Question

D) Accepting an hypothesis doesn't require experiment. 18. Most ancient cultures made A) unorganized observations of the sky. B) no observations of the sky C) organized observations of the sky. D) more news about the sky. 19. The sidereal day is the time it takes the Earth A) to rotate since before it starts rotating. B) to rotate relative to the Sun. C) to rotate around the Sun D) to rotate relative to the back ground stars. 20. The ecliptic is A) It is the apparent path of the Sun in the sky. B) It is inclined 180° relative to the Celestial Equator. C) It crosses the Celestial Equator at the Summer and Winter Solstice. D) the apparent path of the Mars. 21. The time interval from one full or new Moon to the next is called, A) Sidereal Month B) Solar Month C) Helio Month D) Synodic Month 22. When do Astronomers start the Solar Year A) June 21 B) January 1 C) March 21 D) September 23 23. The average time interval between successive passages of the Sun across the celestial meridian is called A) The Sidereal Day B) The Solar Day C) The Mean Solar Day D) The Synodic Day 24. Do Stars remain fixed relative to each other as the move from east to west? A)Yes B) No 25. What does the Moon do in one Synodic month? A) Cycles through a Lunar eclipse. B) Cycles through its phases.

Answer 1

Answers:

Answer 18:organized observation of the sky. They attached legends to lunar cycles, constellations and solar event and were known to make precise observations of the same.

Answer 19:To rotate relative to the back-ground stars (constellation). The sidereal cycle is actually 4 minutes shorter than a solar day.

Answer 20:Apparent path of the sun in the sky.

Note:

• The celestial equator and ecliptic have 23.5. degrees inclination between them.
• It crosses the celestial equator and autumnal and vernal equinox and not solstices.
• Mars doe not have an ecliptic. This term is restricted to the place where the sun and moon have to align to form eclipses.

Answer 21:Synodic month.  It lasts approximately 29.5 days.

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