APOD and General Astronomy Discussion Forum
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geckzilla wrote:
1. Almost, but not quite. The dope sheet might interest you. Each diamond is a return to original position / 1 revolution. 100 frames = 1 day so 3615 is where the system stands after 36.15 days.
What assumptions does Blender make?geckzilla wrote:Same, even with numbers fail fixed. (Guess it's bedtime.) You can see it in the dope sheet. They don't line up again.
No assumptions that I don't make, myself. I included inclination, but not eccentricities, partly because they are so small that they are nearly perfect circles anyway, and my circles are not circles but a series of segments. Size is accounted for. Here's a video I made earlier showing one of the planets passing by another.alter-ego wrote:What assumptions does Blender make?geckzilla wrote:Same, even with numbers fail fixed. (Guess it's bedtime.) You can see it in the dope sheet. They don't line up again.
The orbits have inclination differences and eccentricities. Also, Trappist-1 subtends an angle ranging from 5.5° to 1.4°for planets b thru g.
Regarding angular size alone, if you are not accounting for an extended stellar size, than you could easily be missing a multi-transit event (i.e. the diamonds don't exactly have to line up).
More, because you've left out h.neufer wrote:If these planets ever do line up then:
- 1) every 36.15 days the planets realign
2) every 41st realignment (i.e., 1482.15 days)
the planets are back to their original positions:
---------------------------------------------
41 x 36.15 days = 1482.15 days
......................................
990.991 orbits of b (Gretl)
611.998 orbits of c (Marta)
365.998 orbits of d (Brigitta)
242.991 orbits of e (Kurt)
160.986 orbits of f (Louisa)
119.984 orbits of g (Friedrich)
(More or Less)
It could be... but you'll need a non-scoring blank tile to pull it off, since there are only two "Y" tiles in a normal English game set.BDanielMayfield wrote:Syzygy, a great word to know when playing scrabble.
With an orbital period of 20+15−6 days we're veryBDanielMayfield wrote:More, because you've left out h.neufer wrote:If these planets ever do line up then:
- 1) every 36.15 days the planets realign
2) every 41st realignment (i.e., 1482.15 days)
the planets are back to their original positions:
---------------------------------------------
41 x 36.15 days = 1482.15 days
......................................
980.991 orbits of b (Gretl)
611.998 orbits of c (Marta)
365.998 orbits of d (Brigitta)
242.991 orbits of e (Kurt)
160.986 orbits of f (Louisa)
119.984 orbits of g (Friedrich)
(More or Less)
Which three were thoseBDanielMayfield wrote:
Syzygy, a great word to know when playing scrabble. At least three of these TRAPPIST-1 planets have already been observed in transit at the same time. So TRAPPIST-1, three of its ducklings, and the Earth all got in a row.
Chris Peterson wrote:It could be... but you'll need a non-scoring blank tile to pull it off, since there are only two "Y" tiles in a normal English game set.BDanielMayfield wrote:
Syzygy, a great word to know when playing scrabble.
https://en.wikipedia.org/wiki/Scrabble_letter_distributions#Welsh wrote: Welsh-language Scrabble sets use these 105 tiles:
2 blank tiles (scoring 0 points)
1 point: A ×10, E ×8, N ×8, I ×7, R ×7, Y ×7, D ×6, O ×6, W ×5, DD ×4
2 points: F ×3, G ×3, L ×3, U ×3
3 points: S ×3, B ×2, M ×2, T ×2
4 points: C ×2, FF ×2, H ×2, TH ×2
5 points: CH ×1, LL ×1, P ×1
8 points: J ×1
10 points: NG ×1, RH ×1
Since there are specific tiles for the digraphs that are considered to be separate letters in Welsh orthography (such as DD), it is not permissible to use the individual letters to spell these out. Diacritics on letters are ignored. The digraph PH also exists in Welsh, but is omitted because it is used almost exclusively in mutated words, which the rules disallow. K, Q, V, X and Z also do not exist in Welsh. J does not exist in traditional Welsh either, but it is included as it is used in some borrowed words.>>
While "Z" may not exist in traditional Welsh, it is used. In fact, the common Welsh translation of "syzygy" appears to be... "syzygy" (to the extent that there is no actual Welsh word for that, hence the default being to utilize a borrow word from English... which would be acceptable in friendly Scrabble play).neufer wrote:Chris Peterson wrote:It could be... but you'll need a non-scoring blank tile to pull it off, since there are only two "Y" tiles in a normal English game set.BDanielMayfield wrote:
Syzygy, a great word to know when playing scrabble.
- And the Welsh-language set has no Z :!:
https://en.wikipedia.org/wiki/Scrabble_letter_distributions#Welsh wrote: Since there are specific tiles for the digraphs that are considered to be separate letters in Welsh orthography (such as DD), it is not permissible to use the individual letters to spell these out. Diacritics on letters are ignored. The digraph PH also exists in Welsh, but is omitted because it is used almost exclusively in mutated words, which the rules disallow. K, Q, V, X and Z also do not exist in Welsh. J does not exist in traditional Welsh either, but it is included as it is used in some borrowed words.>>
Chris Peterson wrote:
While "Z" may not exist in traditional Welsh, it is used. In fact, the common Welsh translation of "syzygy" appears to be... "syzygy" (to the extent that there is no actual Welsh word for that, hence the default being to utilize a borrow word from English... which would be acceptable in friendly Scrabble play).
I've been trying to backtrack through the sites I've been reading to find it without success so far, but I saw a graphic last week that showed a TRAPPIST-1 light curve with three partially overlapping transit signals. (For any wishing to help find this info, in addition to this site and Wikipedia I've been reading about this system on the Centauri Dreams and oklo.org websites. Somehow, in following links on one of these sites I was able to peek around Nature's paywall [we no like no stinkin' walls] and I was able to scan a preprint of the discovery paper!) Edit: please disregard the last sentence. See my next post.neufer wrote:Which three were thoseBDanielMayfield wrote:At least three of these TRAPPIST-1 planets have already been observed in transit at the same time.
Thanks, Bruce.BDanielMayfield wrote:
To answer Art's question, the three planet overlapping transit was of the b, c and g planets. Edit: Please apend 'I think' to the previous sentence. However, I just found the source of the three overlapping transit graphic! It is one of the hidden figures located on page 23 of the above pdf. This poorly labed graphic is called "Extended Data Figure 1: Light curve of a tripple transit of planets c-e-f" on page 19.
So I think there may have actually been two tripple plays scored so far: b-c-g and c-e-f!
Er, what are you asking Art? Consecutive how, exactly? And did you mean to moon us here? I thought we were discussing planets.neuter wrote:I wonder if a syzygy of 3 consecutive moons ever happens(...or is that dynamically unstable).
The entire system is dynamically unstable, as is any real-world system with more than two bodies. As a rule, I'd think the sort of syzygy you're considering would be a consequence of orbital resonances, which tend to increase metastability.neufer wrote:Thanks, Bruce.BDanielMayfield wrote:
To answer Art's question, the three planet overlapping transit was of the b, c and g planets. Edit: Please apend 'I think' to the previous sentence. However, I just found the source of the three overlapping transit graphic! It is one of the hidden figures located on page 23 of the above pdf. This poorly labed graphic is called "Extended Data Figure 1: Light curve of a tripple transit of planets c-e-f" on page 19.
So I think there may have actually been two tripple plays scored so far: b-c-g and c-e-f!
I wonder if a syzygy of 3 consecutive moons ever happens(...or is that dynamically unstable).
Principal McGee: We have pictures of you so-called mooners. And just because the pictures aren't of your faces doesn't mean we can't identify you. At this very moment those pictures are on their way to Washington where the FBI has experts in this type of identification. If you turn yourselves in now, you may escape a Federal charge.BDanielMayfield wrote:Er, what are you asking Art? Consecutive how, exactly? And did you mean to moon us here? I thought we were discussing planets.neuter wrote:
I wonder if a syzygy of 3 consecutive moons ever happens(...or is that dynamically unstable).
