An equinox occurs when the Sun is vertically overhead at which latitude?
- A.The Tropic of Cancer
- B.The Tropic of Capricorn
- C.The Equator
- D.The Arctic Circle
Correct answer
Explanation
The correct answer is C, the Equator. Twice a year, about 21 March and about 23 September, the Sun's vertical rays fall on the Equator, the circle of illumination passes through both poles, and day and night are of equal length over the whole Earth, which is what the Latin root of the word equinox, meaning equal night, records. Option A, the Tropic of Cancer, receives the vertical Sun on 21 June, the June solstice. Option B, the Tropic of Capricorn, receives it on 22 December, the December solstice. Option D, the Arctic Circle at 66.5 degrees north, never has the Sun directly overhead at all, because the vertical Sun is confined between the two tropics; it is instead the limit beyond which the midnight Sun and the polar night occur. On the equinoxes the Sun also rises due east and sets due west everywhere.
Read the full article: Gregorian Calendar, Leap Years, Solstices and Equinoxes
Practice Questions
View allWho introduced the Gregorian calendar, which is in civil use across most of the world today?
- A.Julius Caesar
- B.Pope Gregory XIII
- C.Sosigenes of Alexandria
- D.Emperor Augustus
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He issued the bull Inter gravissimas in February 1582 and the new calendar took effect that October, correcting the drift that had built up in the older system and tightening the rule for leap years.
Read the full explanation →How many days were omitted from the calendar when the Gregorian reform came into force in October 1582?
- A.7 days
- B.10 days
- C.11 days
- D.13 days
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Thursday, 4 October 1582 was followed immediately by Friday, 15 October 1582, so ten dates vanished while the sequence of weekdays continued unbroken; the correction was needed because the Julian year of 365.25 days was about eleven minutes too long and had pushed the spring equinox ten days out of…
Read the full explanation →Which of the following is NOT a leap year?
- A.1600
- B.2000
- C.1900
- D.2400
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Under the Gregorian rule a year divisible by four is a leap year, but a century year is a leap year only if it is also divisible by 400.
Read the full explanation →The Gregorian calendar was introduced to correct the errors of which earlier calendar?
- A.The Julian calendar
- B.The Saka calendar
- C.The Hijri calendar
- D.The Vikram Samvat
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The Julian calendar, in use from 46 BC, assumed a year of exactly 365.25 days, which is about eleven minutes longer than the true tropical year of roughly 365.2422 days, so it gained a day about every 128 years and the equinox slid out of place.
Read the full explanation →Which of the following calendars will be the same as the calendar for the year 2003?
- A.2014
- B.2013
- C.2012
- D.2011
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A year repeats another year's calendar when the odd days between them add up to a multiple of seven and both years are of the same kind, ordinary or leap.
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