Universe Puzzle

Universe Puzzle No. 2

21 Feb , 2010 by

To start your working week, here’s a little something to help you sharpen your brain (OK, it’s already the end of the day for our viewers in New Zealand and Australia, so for you a little pick-me-up after a hard day’s work).

As with last week’s Universe Puzzle, something that cannot be answered by five minutes spent googling, a puzzle that requires you to cudgel your brains a bit, and do some lateral thinking. And a reminder: this is a puzzle on a “Universal” topic – astronomy and astronomers; space, satellites, missions, and astronauts; planets, moons, telescopes, and so on.

There are no prizes for the first correct answer – there may not even be just one correct answer! – posted as a comment (the judge’s decision – mine! – will be final!), but I do hope that you’ll have lots of fun.

What’s the next number in the sequence? 1655, 1671, 1672

Post your guesses in the comments section, and check back on Wednesday at this same post to find the answer. To make this puzzle fun for everyone, please don’t include links or extensive explanations with your answer, until after the answer has been given. Good luck!

PS There’s an open question on last week’s puzzle too (scroll down to the bottom of the comments).

UPDATE: Answer has been posted below.

Was this too easy perhaps? Maybe only five minutes’ spent googling was all that was needed to find the answer?

Christiaan Huygens discovered the first known moon of Saturn. The year was 1655 and the moon is Titan.

Giovanni Domenico Cassini made the next four discoveries: Iapetus (in 1671), Rhea (in 1672), …

… and Dione (in 1684), and Tethys (also in 1684).

What about Cassini’s discovery of the Cassini Division, in 1675?

Well, the discovery in 1655 was not made by Cassini, the rings of Saturn were discovered by Galileo (in 1610), and so on.

So, no, 1675 is not the next number in the sequence.

So the answer is: 1684

Source: JPL/NASA

It’s amazing to reflect on how much more rapid astronomical discovery is, today, than back then; 45 years from the discovery of Saturn’s rings to Titan, another 20 to the discovery of the Cassini Division; 16 years between the discovery of Titan and Iapetus; … and 74 years from the rings to Dione and Tethys.

And today? Two examples: 45 years ago, x-ray astronomy was barely a toddler; and 74 years ago radio astronomy had just begun. Virtually all branches of astronomy outside the visual waveband went from scratch to today’s stunning results in less time than elapsed between the discovery of Saturn’s rings and its fourth brightest moon!

Check back next week for another Universe Puzzle!


Sort by:   newest | oldest | most voted
Manjula
Member
February 22, 2010 12:36 AM

1789 – Discovery of Mimas and Enceladus by William Herschel

Bill
Member
February 22, 2010 2:45 AM

I agree with bystander. The moons Tethys and Dione were discovered in 1684.
Mimas and Enceladus were discovered in 1789; therefor the next number in the series is :

1684

Bill
Member
February 22, 2010 2:50 AM

It would appear that the famous site that most went to, but didn’t check other sites, is incorrect about the dates of discovery for Tethys and Dione.

J. Major
Member
February 22, 2010 7:26 AM

1675 – Cassini discovers his namesake division in Saturn’s rings.

?

Chrissyo
Member
February 22, 2010 12:27 AM

My guess is the years of discovery of some of Saturn’s moons.

Titan – 1655
Iapetus – 1671
Rhea – 1672

bystander
Member
bystander
February 22, 2010 12:29 AM

8 moons of Saturn were discovered by direct observation.

1655 Titan discovered by Christian Huygens
1671 – 1672 Tethys, Dione, Rhea, and Iapetus discovered by Giovanni Cassini
1789 Mimas and Enceladus discovered by William Herschel
1848 Hyperion discovered by WC Bond, GP Bond, and William Lassell

bystander
Member
bystander
February 22, 2010 12:39 AM

Actually 1684 was when Tethys and Dione were discovered

Chrissyo
Member
February 22, 2010 1:01 AM

Doh! Got caught up in the first three numbers and forgot to post the next number in the sequence! Well, others have beaten me to it. razz

YogieOne
Member
YogieOne
February 22, 2010 1:19 AM

Next in sequence is 1789 –
When William Herschel Discovered Mimas, a satellite of Saturn.

1655 = Christiaan Huygens found Titan Saturns Largest satellite.
1671 = Giovanni Cassini discovered Iapetus, one of Saturns moons.
1672 = Giovanni Cassini discovered Rhea, one of Saturns moons.

Fluffmachine
Member
Fluffmachine
February 22, 2010 8:37 AM

1674 ? Maybe.

pikoia
Guest
pikoia
February 22, 2010 8:51 AM

Next no: 1675: Cassini discerned the Cassini Division
And 1684: Cassini discovered Tethys & Dione
Dates:
1655: Hyugens discovered Titan
1671: Cassini discovered Iapetus
1672: Cassini discovered Rhea

cole
Member
cole
February 22, 2010 9:55 AM

Not 1672.16? History trumps math?

m0okie
Member
m0okie
February 22, 2010 10:59 AM
’68 -Oxford’s Savilian professor of geometry John Wallis publishes “The Arithmetic of Infinitesmals” which assigns numerical values to spatial indivisibles as a way to include negative and fractional exponents in determining ways to find a square whose area is equal to that of a given circle. This allowes for Cassini, after discovering Saturn’s satellite Iapetus in ’71, and his discovery of another sattelite (Rhe), and later or earlier, not sure, but to dare to approximate the distance between the sun and Earth, becoming the first to arrive at a close calculation. Cassini also discovered Tethys and Dione in 1684 after discerning in 1675 the gap in Saturn’s rings, this is later known as Cassini’s Division…. ??? am I… Read more »
Astrofiend
Member
Astrofiend
February 22, 2010 2:42 PM

I’m liking these Jean!

krishna
Member
February 22, 2010 11:11 PM

1789 – Mimas,Enceladus

shah_nikhilesh
Member
shah_nikhilesh
February 23, 2010 12:55 AM

New planetary satellites came into focus: Saturn’s Titan (Huygens, 1655), followed by Lapetus (1671), Rhea (1672), and Tethys and Dione (1684), all discovered by Cassini.

So, my answer is 1684.

If its right, then it took less than 5 minutes on google… smile

mcsejung
Member
mcsejung
February 23, 2010 4:15 AM

1676 – Cassini discovers the Cassini Division between the A Ring and the B Ring.

mbarricarte
Member
mbarricarte
February 23, 2010 5:08 AM

1678

Geology
Member
Geology
February 23, 2010 5:23 AM

The development of intergral calculus:

1655: “Arithmetica Infinitorum” [Infinitesimal Arithmetic] by John Wallis
(3 Dec 1616-?) describes infinite series, and advances towards Integral Calculus

1671: James Gregory discovers what we call the Leibniz Series (an
infinite series that sums to pi/4)

1672: “Il Problema della Quadratura del Circolo” [The Problem of
Circle-Squaring] by Pietro Mengoli (1625-?) has an assortment of infinite
series, infinite products, the sum of the reciprocals of traingular
numbers, and the divergence of the harmonic series (i.e. that the sum
increases without limit of 1/1 + 1/2 + 1/3 + 1/4 + 1/5 + 1/6 + …)

Probably not the correct answer but worth a shot.

Geology
Member
Geology
February 23, 2010 5:36 AM

Left off the last part…

1676: There is a mostly polite but very intense controversy between Newton
and Leibniz as to who invented what parts of Calculus first.

wpDiscuz