THE SOUTHWORTH PLANETARIUM
207-780-4249 www.usm.maine.edu/planet
70 Falmouth Street Portland, Maine 04103
43.6667° N 70.2667° W
Founded January 1970
Julian date: 2457641.16
"An out of the way mirror pool in which the Universe occasionally admires itself."
This quiz is dedicated to Keith Heldenbrand who, someday, might actually learn to read a calendar!
THE DAILY ASTRONOMER
Friday, September 9, 2016
Quiz II: Summer time!
Happy 18th birthday, infernally adorable adult daughter. Despite a maudlin father's ardent pleas, you decided to grow from infancy through adolescence into early adulthood: an Olympian metamorphosis that seemed to transfigure you from a five year old cuddle bear to a fine young lady over the course of about a week. Happy birthday, sweetheart.
No, Keith, summer is not over!
Yes, Labor Day now belongs to the ages. The tourist swarms have vacated the beaches, herds of disgruntled children have lumbered back to school and the NFL season (now officially classified in New England as a religious event) is about to kick off. All we need now to complete the autumnal motiff are crisp apples on counter tops, desiccated leaves gathered on fading grass and a pumpkin orange moon rising over smoking chimneys. However, we haven't quite reached that stage because, well, SUMMER ISN'T OVER! Astronomically, we have thousands upon thousands of minutes remaining in what has turned out to be the most gloriously hot, sublimely dry and exquisitely beautiful summer ever seen on the south side of the pearly gates. So, Keith, since we're still in summer, we decided to honor summer with a sweet and sultry summer time quiz!
1. Astronomically, summer ends at the moment of the _______________________. This year, that event falls on September _________.
a. autumnal solstice; 21
b. autumnal equinox; 22
c. vernal equinox; 22
d. vernal solstice; 21
2. Which of the following statements is/are true?
a. Summer is our longest season
b. The North Pole goes dark on the autumnal equinox
c. Earth is closest to the Sun in the summer
d. All the seasons have equal duration
3. What season is it on the equator at the moment?
a. summer on the equator in the western hemisphere; winter on the equator in the eastern hemisphere
b. summer
c. the equator doesn't have seasons
d. winter
4. In Portland, Maine (latitude approximately 43 degrees), what is the highest altitude the Sun will ever attain? (Yes, it attains this altitude on the summer solstice.)
a. 90 degrees
b. 70.5 degrees
c. 66.5 degrees
d. 47 degrees
5. Ok, enough science for a bit. A little popular culture. What movie was considered the biggest box office bomb for the summer 2016?
a. Ben Hur
b. Ghostbusters
c. Finding Dory
d. Tarzan
6. True or false: The Harvest Moon can sometimes occur in the summer.
7. July and August were named for Julius Caesar and Augustus Caesar, respectively. For whom is June named?
a. Juno, Roman goddess of marriage
b. Junius Caesar
c. It isn't named for anybody. The word "June" is derived from the Etruscan word for "heat"
d. Janus, the god of beginnings and endings
8. Which ONE of the following is not a constellation within the Summer Triangle?
a. Aquila the Eagle
b. Lyra the Harp
c. Sagittarius the Archer
d. Cygnus the Swan
9. What is the highest temperature ever recorded in the United States?
a. 123 F
b. 128 F
c. 134 F
d. 167 F
10. What does the word "solstice" actually mean?
a. "summer"
b. "Sun still"
c. "high Sun"
d. "sleep"
ANSWERS
1. b. autumnal equinox; 22
Autumn begins on the autumnal equinox. This year, that equinox occurs on September 22 at 10:21 a.m. We should call this event the "September equinox," as it will mark the first day of spring in the Southern Hemisphere.
2. a. Summer is our longest season
The lengths of each season (for the Northern Hemisphere) are as follows:
Winter 88.9 days
Spring 92.8 days
Summer 93.6 days
Autumn 89.85 days
As for the other statements: The North Pole does not go dark on the autumnal equinox. Actually, the Sun is still visible on the autumnal equinox at the North Pole because atmospheric refraction tilts the sun's image up along the horizon by half a degree, equal to the Sun's apparent angular diameter. Even when the Sun sets a few days later, the North Pole experiences a slowly fading twilight over many weeks.
3. c. the equator doesn't have seasons
The equator is a line of no thickness. If one were standing on the equator facing west, the north part of the body would be experiencing summer and the south part would be in winter.
And, the Sun is closest to Earth at perihelion, which occurs between the 1 - 4 of January. The Sun is farthest from Earth at aphelion, which occurs around July 3 - 5. So, we are farthest from the Sun in summer!
4. b. 70.5 degrees
Imagine projecting Earth's equator onto the night sky. Further imagine that it were luminescent and visible everywhere. Its angle above an observer's horizon would depend on the observer's latitude. At the equator, it would be directly overhead (at the zenith), or 90 degrees above the southern horizon. At 10 degrees N, it would be 80 degrees above the southern horizon. At 20 degrees N, it would be 70 degrees above the southern horizon. Here, we've established a nifty inverse relation. The angle this projection would make above an observer's southern horizon equals 90 - the observer's latitude. Portland's latitude is 43 degrees N, so this equatorial projection (properly called the Celestial Equator) would be 47 degrees above due south.
The Sun's apparent position relative to this celestial equator varies throughout the year. The Sun appears directly on this equator on both equinoxes. On the summer solstice, the Sun is 23.5 degrees north of it because Earth is tilted on its axis 23.5 degrees. The Sun reaches its highest altitude in our sky when it passes due south -or at upper culmination. On the autumnal equinox, its highest angle is 47 degrees. On the summer solstice, it is 47 + 23.5 = 70.5 degrees.
5. a. Ben Hur
According to industry estimates, this move might lose $120 for Paramount/MGM.
Roar!
6. TRUE!
The Harvest Moon is the full moon that occurs closest to the autumnal equinox. This full moon can occur just before or just after the equinox,
7. a. Juno, Roman goddess of marriage
January is named for Janus, the god of beginnings and endings
8. c. Sagittarius the Archer
Sagittarius is a prominent southern summer constellation, but it is not part of the Summer Triangle.
9. c. 134 F
Death Valley, July 10, 1913
10. b. "Sun still"
When the Sun reaches either solstice, it appears to linger at this point for a few days before either descending after the summer solstice or ascending after the winter solstice.
____________________________________________________
RADIO ASTRONOMY ON WMPG 90.9 FM
Next episode: "The Coldest Place in the Universe."
Friday, September 9, 2016 at 1:00 p.m
A discussion about the Cold Atom Laboratory slated to be
installed in the International Space Station. The guest will be
Dr. Thomas Jarvis, one of the research scientists working on this
project.
_______________________________________________________