December Quiz posted

[OzEclipse]

The December quiz is now posted and ready to play. It's another challenging one and I've aimed at a group average score of 50%

app.php/quiz/play/11

I'll be travelling over the summer holiday period from about a week before Christmas for a few weeks so the January quiz release and the December round up might be late or if too late I might hold it over to February.

Seasons greetings to all.........see you next year

Joe


@SparWeb @kt4hx @sdbodin @AntennaGuy @JayTee @Bigzmey @messier 111 @pixelsaurus @Gfamily @carastro @Juno16 @Graeme1858 @Juno16 @bobharmony @helicon @Gordon @SkyHiker @Michael131313 @JSBach1801 @astrorlk @Burrman@andrewsscope@jerrysykes @MrShorty @meredithw13 @Raymondhow

[KathyNS]

80% in 4 minutes. Can I guess well or what?

[helicon]

20.00 in 6 minutes. I did not get correct any question I guessed on.

[Gordon]

I thought the object was to get them all wrong.
10%.......

[SkyHiker]

I had 50% but that's more than I deserved.

[Gfamily]

80% in 5 minutes. Happy with that. A good quiz - had to think twice about Q1 and Q2, but managed not to embarrass myself on those two.

Really appreciate these Quizzes, it really helps to keep me on my astronomical toes.
Have a good 'summer' break - we're in the middle of a real cold snap, so that seems very odd.

[sdbodin]

WOW 100%... I am flabbergasted... at least 4 straight out SWAGs.

Going to book a room at my nearby casino while the luck holds,
Steve

[AntennaGuy]

60%. Woo hoo!

[Michael131313]

50%. That's with some luck. Thanks for the fun, Joe.

[messier 111]

total disaster, 20%
Thanks for the quiz Joe.
much easier with the reading side translation.

[Juno16]

30% in 5 min (not sure if time is relevant).

10 guesses with 3 hits!

Thanks Joe! @OzEclipse

[OzEclipse]

30% in 5 min (not sure if time is relevant).

10 guesses with 3 hits!

Thanks Joe! @OzEclipse

Hi Jim,
Time is not especially relevant.
I have to set a time limit in order to submit the quiz. If two people both get 100%, I’ll rank them by completion time. This is usually only required in the easy quizzes where everyone is bunched up on 80, 90, 100 %. It’s rarely an issue for these challenging quizzes.
Cheers
Joe

[JayTee]

70%. Paying for some poor guesses.

[Graeme1858]

70%

Graeme

[bobharmony]

70% - I'll take it!

Bob

[OzEclipse]

December 2023 Quiz Followup

The current quiz tool we are using does not allow for any explanatory statements with the marking sheet. For anyone confused by any of the answers, I have prepared the notes below.

Q1. You are standing on Antarctica at the Earth's south pole. Approximately when does the sun rise?


Answer: September 21
Comments: Standing at the south pole, the celestial equator traces 360 degrees all around the horizon. The Sun, crosses the celestial equator and moves into the southern hemisphere at the autumnal equinox on September 21 thus rising at the south pole.




Q2. You're still at the south pole. When you watch the sun rise, what direction does it rise? (for the pedants – we're looking for the true bearing not magnetic)


Answer: North
Comments: This one wasn't complicated. Standing at the south pole, every direction you look is north.




Q3. What is the meaning of the term “Local Hour Angle” when used in astronomy and surveying?

Answer: The angle from the meridian of the observer's location to the meridian of an astronomical object of interest.

Comments: The local hour angle measures the angle, expressed in hours of RA, an object of interest is located before or after transiting. It is used in the formula to calculate rise and set time of an object above a zero or an artificial non-zero horizon.

The hour angle is defined as “the angle between the meridian running through the observer’s position and the meridian passing through the celestial body”.




Q4. The annual Leonid meteor shower results from the Earth passing through a debris field left in the orbit of comet Tempel-Tuttle. Periodically, the Earth passes through a denser part of this debris field resulting in an incredible shower of fireballs with a very high hourly rate. One such display in the past produced 1000 Leonids in fifteen minutes. How many years is this period?

Answer: 33 years/ans

Comments: Historical records contain records of large outbursts every 33 years. These were recognised empirically until the 20th century when Research by Kondrat'eva, Reznikov and colleagues[42] at Kazan University had shown how meteor storms could be accurately predicted, but for some years the worldwide meteor community remained largely unaware of these results. The work of David J. Asher, Armagh Observatory and Robert H. McNaught, Siding Spring Observatory[8] and independently by Esko Lyytinen[43][44] in 1999, following on from the Kazan research, is considered by most meteor experts as the breakthrough in modern analysis of meteor storms. Whereas previously it was hazardous to guess if there would be a storm or little activity, the predictions of Asher and McNaught timed bursts in activity down to ten minutes by narrowing down the clouds of particles to individual streams from each passage of the comet, and their trajectories amended by subsequent passage near planets. However, whether a specific meteoroid trail will be primarily composed of small or large particles, and thus the relative brightness of the meteors, was not understood. But McNaught did extend the work to examine the placement of the Moon with trails and saw a large chance of a storm impacting in 1999 from a trail while there were less direct impacts from trails in 2000 and 2001 (successive contact with trails through 2006 showed no hits).[41]

The next 33 year maximum occurs in 2033/34. Analysis of streams has predicted storm peaks in both years with ZHR peaks of 300-400. No storms with thousands per hour are predicted for those years.




Q5. Who defined the 88 constellation names and physical boundaries commonly in use today?


Answer: The International Astronomical Union in 1928


Comments: Although all the listed civilisations and organisations named some constellations, the constellations and their boundaries were not formally and precisely defined until the IAU did it in 1928.




Q6. Through which zodiac or ecliptic constellation does the 0 hrs Right Ascension meridian pass?
Answer: Pisces / Poissons
Comments: Although traditionally the midnight transit of the star Hamal in Aries/Verseau was used to determine the vernal equinox and the zero hour of RA, Zero RA crosses the ecliptic in Pisces.




Q7. Which constellation contains the most northern declination of the ecliptic?

Answer: Taurus and Gemini (equal)

Comments: The ecliptic hits its northernmost point almost equally in Taurus and Gemini so I allowed both as correct answers. Other answer constellations are further north but the ecliptic passes close but does not pass through these constellations.




Q8. Pulsars can pulse very quickly indicating spins of hundreds of RPM up to 43000 RPM for the fastest known puslar rotation. What is thought to cause them to rotate so fast?

Answer: Conservation of angular momentum. As the neutron star collapses, conservation of angular momentum causes a corresponding increase in rotation rate.

Pulsars are neutron stars. When the progenitor star collapses, like an ice skater tucking their arms in during a spin, the rotational speed increases due to conservation of angular momentum. We can infer that a star that rotates at 43000 RPM has undergone a much greater collapse than a star rotating at a slower speed.




Q9. When looking through a simple straight through optical finderscope with eyepiece fitted, the image you observe is?

Answer: Inverted and reversed left to right.


Comment: This is similar to a question in a previous quiz. Refracting lenses are radially symmetric. The objective both inverts and reverses the image. The eyepiece simply allows magnified inspection of that image.



Q10. Which constellation contains the 1st magnitude star Fomalhaut?

Answer: Pisces Austrinus / Poissons Austrinus

Comment: Formalhaut is the 18th brightest star in the sky, Mag 1.16 and 0.02 mag fainter than 17th brightest star Pollux, and located in the constellation of Pisces Austrinus near Aquarius.

[OzEclipse]

Here are the December results. As usual, I only identify the high scorers leaving it up to individuals to publish lower scores or not.

Congratulations Steve Bodin who won the quiz with a perfect score. Kathy and Owen came in equal second with 80% each.