It's not only the pupils at Farthingbottom School that come from famous families, some of the teachers do too. One of these is the popular chemistry teacher, Dr M. Langley. He's a real sun-worshipper and spends a lot of time topping up his tan. Unfortunately he's not in today because he hasn't achieved his target of 811.44 hours exposure (and obviously turning orange is far more important than teaching his pupils).

Today his less popular brother Dr H. Langley is taking his class. He hates chemistry (and incidentally he hates cryptography even more).

"I don't know why my brother has to spend this many weeks lazing around. Here, take these and complete them" he says as he passes out some sheets of paper, "and tell me what record was held for 52 years."

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The pupils look at the pieces of paper and then Felix shouts out "This isn't a periodic table, is it, sir?"
"That's right", answers Dr Langley
"Some of these letter combinations appear more than once", chips in Randolph.
"Of course they do" he replies sharply.
"Are we supposed to be filling in the grey boxes?" asks Marc-Frances.
"No, idiot, the yellow ones", snaps the teacher.
Hesitantly Portia raises her hand and says "Sir, are all these entries up to date and complete?"
"Well, at least there's one bright one in the class", he says. "As of today (1st October, 2015) the entries are correct as I have determined them, but this is not a complete set. I considered there was more than enough information for you without expanding the table any further."

Question: Can you determine which record Dr Langley is referring to?

Edit: After a considerable time during which there had been some muttering, but not a lot of progress, Dr Langley shook his head and said,

"I have heard lots of muttering about stars, but this is not my brother's class. You already know all you need to about his obsession (or would if you could do simple arithmetic). And his obsession should lead the search to find mine. I blame it all on our ancestors. Now hurry up and get finished before I have to throw out the whole chart and start all over again!"

  • $\begingroup$ Does outer-space have anything to do with the actual solving of the puzzle? If not, please take it out. $\endgroup$
    – warspyking
    Oct 1, 2015 at 16:57
  • $\begingroup$ @warspyking Oh yes! Both the answer and the route there. $\endgroup$
    – Gordon K
    Oct 1, 2015 at 17:02
  • 2
    $\begingroup$ This is tough. Is the dY for the H (y-axis being height) or for the letters, hm... This has something to do with stars, I think. Technical names or regions of space. And maybe brightness ratings or distances. $\endgroup$ Oct 1, 2015 at 17:09
  • $\begingroup$ I would also guess it's about stars. My first reaction to dY is declination, and H could be distance (ly) or magnitude? Just musing. $\endgroup$
    – dpwilson
    Oct 1, 2015 at 17:27
  • $\begingroup$ I tried coordinates: stellar-database.com the closest match using the first yellow box was off by a bit, it was using the top number as Y, left number as Z and right number as X. So I'd say that doesnt work. (gave me J. Herschel 5173 at 0.9 ly from that spot btw) $\endgroup$ Oct 1, 2015 at 20:24

1 Answer 1


I believe the blank spaces are


The meaning of these numbers are

Asteroid designations. The dY is the number of years ago (counting from 2015) it was discovered, the H is the absolute magnitude, and the letters plus the "atomic number" (to use the periodic table comparison) make up the provisional designation.

So, for example,

The very first block (in the Hydrogen position) would be asteroid 2004 LJ1, which has an absolute magnitude of 15.4.

The numbered clues, in order, spell out

HERMES, which was an asteroid discovered in 1937. At the time, it was the closest observed near-miss between an asteroid and Earth. This record held until 1989, 52 years later, when a closer orbital pass was observed, this time of asteroid Asclepius.

The amount of time that M Langley sunbathes for, 811.44 hours

Measured in weeks, as suggested by his rude brother, is 4.83, the absolute magnitude of the sun.

The name Langley itself refers to

Samuel Pierpont Langley, who did quite a bit of research on the Sun, and invented a device called the bolometer, which measures absolute magnitude. Magnitudes of stars and Solar System bodies are calculated differently, because putting rocks on the same scale as nuclear furnaces would be meaningless. The absolute magnitude of a star has the symbol M, and the absolute magnitude of a planet/asteroid has the symbol H. Just like the brothers and their respective obsessions.

  • 1
    $\begingroup$ I just realized I read this: "No, idiot, the yellow ones", snaps the teacher. as sarcasm , and never thought twice on it -_- > So I was trying to find the grey boxes $\endgroup$ Oct 9, 2015 at 18:44
  • $\begingroup$ I can't believe I made such a basic mistake (hangs head in shame and quickly corrects the 62 to 52). Well done regardless. Can you explain anything about the H Langley and M Langley and the time spent sunbathing? $\endgroup$
    – Gordon K
    Oct 9, 2015 at 19:46
  • $\begingroup$ Well Samuel Langley did a lot of work with sunspots, and 811.44 hours is somewhere in the region of the sun's rotation period (though it varies between the equator and the poles), but I came up a bit short on those points. $\endgroup$ Oct 9, 2015 at 20:08
  • $\begingroup$ @TheHandofJustice How does Dr H Langley refer to the 811.44 hours? Does that give you a more meaningful number? $\endgroup$
    – Gordon K
    Oct 9, 2015 at 20:24
  • 2
    $\begingroup$ 811.44 hours, in weeks, is 4.83, the sun's absolute magnitude. $\endgroup$ Oct 9, 2015 at 20:29

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