Talk:Halley's Comet

Halley's Comet or Comet Halley discussions Perihelion table issues

Pronunciation

Quote "Note. The most standard pronunciation of "Halley" is /hæli/, to rhyme with "valley." The pronunciation /hejli/ (to rhyme with "Bailey") is thought to have originated by relation with the rock group Bill Haley & His Comets."

The "rhymes with valley" pronunciation is very common. However, it is thought that the way Mr Halley said his own name was that the Hall part rhymed with Paul, tall and call, then the ey as the ey in valley.

Patrick Moore once famously said on television that the pronunciation should probably be {first part rhymes with tall} but that {rhymes with valley} was so widley used it could probably not be changed.

Songwriter 23:38 9 Jul 2003 (UTC)

Photograph

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"The 1910 approach was notable for ... being the first approach of which photographs exist"

There's a photo of that on Royal Astronomy Society, which claims to be "copyright 2003" (how can that be so if the photo was taken in 1910?) Are there any photos of this encounter that we could use? Ojw 5 July 2005 12:03 (UTC)

Anything before 1922 is public domain in the US, so any photo at all should be usable. Ken Arromdee 21:01, 22 December 2006 (UTC)

Dear NASA

Dear NASA,

Would you plant a telescope in orbit around Halley's Comet when it returns in 2061? We have plenty of time to plan for it! oneismany 10:45, 15 November 2005 (UTC)

Not a complete sentence

The first sentence is not a complete sentence. If I am incorrect, please tell me.Sidious1701 22:16, 12 January 2006 (UTC)

Location-specific descriptions

The first paragraph, prior to 14/9/2006, read, "Halley's comet last appeared in the inner Solar System in 1986, and will next appear in the summer of 2061."

Please try to avoid such location-specific descriptions as "in the summer", as this is a global wiki, and the same time is the winter for the southern hemisphere.

References

Would anyone object to me switching the article to use the footnotes reference style? Mike Peel 19:51, 15 November 2006 (UTC)

internal contradiction

The article says that people noticed that the comet showed up evey 70 years in 66 CE, yet it also says that no one noticed that it was the same reoccuring object until the 17th century. --Arctic Gnome 09:46, 6 December 2006 (UTC)

The link in the text did not specify that the object described in 66 CE was definitely Halley's Comet. This may or may not be original research. I have added a citation needed tag. (How nice to no longer deal with complaints about the article's name.) Dr. Submillimeter 18:45, 7 December 2006 (UTC)

The following quote IMHO also contradicts with Halley being the first to discover it was a reoccurring object:

"Habitual observations and calculations of appearances after 240 BC are recorded by Chinese, Babylonian, Persian, and other Mesopotamian texts.

Maggy Rond (talk) 11:20, 19 November 2008 (UTC)

Pronunciation Question

It says that the "most standard pronunciation of 'Halley' is /hæli/, to rhyme with 'valley'." Does the æ make that sound? The reason I ask is because I always thought it made a long a sound, as in the end of "Astronomiæ Cometicæ" (which is part of a title cited at the bottom of the page). Could someone clear that up for me?

Lollipop09 04:25, 11 January 2007 (UTC)

This symbol is being used in accordance with the IPA (q.v.); the ae ligature is used to represent the 'a'-sound in 'valley' in RP, amongst other dialects. —Preceding unsigned comment added by 88.105.21.223 (talk) 17:22, 7 October 2007 (UTC)

I understand your confusion, Lollipop09. Having studied Latin at school in the '60s (and Astronomy most of my life), I also would pronounce 'ae', often ligatured as 'æ', long (rhyming with 'eye') in Latin or Latin-derived words.

(There are of course more than one set of Latin pronunciation conventions, as for example "Jooliuss Seezer" vs "Yulius Kaizar" - A. P. Herbert illustrated this amusingly in one of his 'Misleading Cases', when a newly qualified barrister educated in the newer 'historically accurate' school came up against a judge used to the more traditional 'Legal Latin' tradition: I have regrettably mislaid the volume so cannot give a more precise reference.)

However, when IPA was devised it was not intended that the 'æ' symbol should represent the same sound as 'ae' happens to in Latin. 87.81.230.195 (talk) 01:28, 29 March 2008 (UTC)

Four times the size of Venus?

The article says that on its 1066 appearance it was "four times the size of Venus, and ... shone with a light equal to a quarter of that of the Moon." Has there been vandalism? Is that the wrong way around? Venus has no visible disc to the naked eye, so "four times the size of Venus" is sort of meaningless. Dpbsmith (talk) 20:22, 2 March 2007 (UTC)

Well, it's been that way since the article was created in 13:40, 26 March 2002! Dpbsmith (talk) 20:24, 2 March 2007 (UTC)

Apparently this is indeed what the 1911 Britannica says:[1]. I'm sure it's an error. Wouldn't it be neat to have found an error in Wikipedia and the Encyclopaedia Britannica on the same day... in fact, the same error? Dpbsmith (talk) 20:29, 2 March 2007 (UTC)

Halley's comet - a comi ttht takes 76 years to journey from beyond Neptune to around the sun and back; last seen in 1986

Although Venus is not resolvable as a disc to the average eye (some have claimed to see the crescent phase, however) - you can definitely tell that is has a reasonably large angular diameter - i.e. you can tell that it is not a point source of light like the stars appear to be. At closest approach to Earth, Venus' diameter is of the order of 1 arcminute - around 1/30th of that of the Moon. So "4 times the size of Venus" doesn't mean nothing - you can percieve that Venus does have a "size". I suspect, however, that in this instance, size might mean brightness - from what I have seen in some older texts, brightness and size can be almost interchangable. Richard B 13:04, 19 March 2007 (UTC)

See Angular diameter and naked eye. Venus appears relatively large as well as very bright. -- Kheider (talk) 17:02, 20 November 2007 (UTC)

Future of the comet

but of a stupid question, but is the comet shrinking? becuase the tail of the comet is due to parts of the comet breaking off and dust, ice and parts of the comet being thrown into space. therefore does that mean that eventually the comet will be destroyed? or does it 're-build' itself in space, maby by impacting with other objetcs. —The preceding unsigned comment was added by 168.224.1.14 (talk) 07:57, 4 April 2007 (UTC).

Eventually, yes. When I don't know. Halley looks a bit like a peanut, and some have speculated that it is in the process of breaking into two separate objects. Serendipodous 07:59, 4 April 2007 (UTC)

History of the comet

roughly translated quote from Dutch Wikipedia:

"Observation of other comets shows that comets in general have a shorter life when it comes near the sun more often. 
"Dutch astronomer Jan Hendrik Oort supposed the existence of a distant cloud with millions of comets. 
"Logical question is how a short period comet like Halley's can exist so long. 
"The answer is that this comet also once escaped from the Oort cloud, perhaps about 1000 years ago. 
"Because of its relatively low mass it gets easily pulled out of its orbit. 
"This is how it became a short period comet. 
"This also meant the faith of the comet, in a few centuries it will cease to exist.

If the writer is correct, it would mean that most sightings before about Charlemagne might will be one or several other comets. Anyhow the very precise calendar dates given in this article even for sightings in middle ages and BC seem a bit ridiculous to me. We all know that a comet does not "pop up" or disappears on a single date. The time tables of several civilisations have changed significantly over the centuries. And I know two perfect examples of Dutch Renaissance people who didn't even know the exact year they were living in. -compare the dates of Erasmus' letters with the facts he describes; he was either clearvoyant (very unlikely) or he simply didn't know which year it was. -In the Dutch city of Bergen op Zoom around 1634/1639 there were two church ministers recording their baptisms in the same book. One was convinced it was 1634, the other that it was 1639. In that area and in those days you either see the year only once on the page of the first of Januari or in some cases on top of each page. These two wrote the year behind each date, regularly crossing out the years written by the other. These records can be seen on markiezenhof and further. Notice the difference in handwriting, they even used different pens. Maggy Rond (talk) 11:15, 19 November 2008 (UTC)

Recent added paragraph

I've tidied up the recently added paragraph on Halley's composition but it could use some refs. Serendipodous 12:52, 15 May 2007 (UTC)

Unfair?

I think the following paragraph: "The 1986 approach was the least favourable for Earth observers of all recorded passages of the comet throughout history: (...) Further, the comet appeared brightest when it was almost invisible from the northern hemisphere in March and April, prompting many amateur astronomers to travel to the southern hemisphere for a glimpse of the interloper." is clearly Northern Hemisphere-centered, as it states one of the reasons the 1986 visit was "the least favourable" is that it was almost invisible in the north, and that people had to go south. —Preceding unsigned comment added by 200.124.57.108 (talk) 07:29, 11 November 2007 (UTC)

That entire paragraph is unsourced and is going to have to be revised. Serendi^podous 09:01, 11 November 2007 (UTC)

I don't think this is really as biased as it appears at first glance. Firstly, the general unfavourability of the 1986 apparition applied to the whole world, due to distance and relative Sun positions; this should not be conflated with the additional unfavourability for Northern Hemisphere observers around the time of closest approach to Earth.

Secondly, the large majority of (though of course not all) amateur astronomers did in 1986 and do today live in the NH, due simply to the geographical distribution of the continents and of human populations within them. I think a straightforward geographical fact is in danger of being taken for some sort of anti-SH-resident bias.

Certainly a good many NH amateurs did indeed 'fly south for the comet' in 1986. I agree the para may need tweaking and citations (I'll dig into my paper archives of 'Sky & Telescope Magazine' to see if I can find some), but it's not substantially incorrect. 87.81.230.195 (talk) 02:08, 29 March 2008 (UTC)

Picture from Giotto

Why not include the picture of the nucleus from the Giotto spacecraft flyby back in 1986? —Preceding unsigned comment added by 138.227.189.9 (talk) 12:52, 17 January 2008 (UTC)

Fiction novels

Heart of the Comet (1986) is a great SF novel where a colony was set up inside Halley's comet on its 2061 return to perihelion. If you ain't read it yet, this is the one for you! Pomona17 (talk) 12:48, 14 February 2008 (UTC)

Comet Halley, NOT "Halley's Comet"

The proper way to say the name of a comet is to say the word comet before a name. I think "Halley's Comet" should be placed after "Comet Halley" in the opening sentence. This would be much more proper. TheOtherSiguy (talk) 22:24, 4 March 2008 (UTC)

Let's not do this again. "Halley's Comet" is overwhelmingly the common name. --Trovatore (talk) 02:19, 5 March 2008 (UTC)

The common name policy refers to the article name, not the text. Saros136 (talk) 08:19, 5 March 2008 (UTC)

Best to let this one go, but the Wikipedia naming conventions for astronomy recommends Comet Halley . But Halley's Comet, for the article name. Saros136 06:15, 5 March 2008 (UTC)

Hence the value of REDIRECT pages. Baseball Bugs ^{What's up, Doc?} 06:32, 5 March 2008 (UTC)

The usage in the articles and in the titles(redirects) are different issues. Encyclopedia Britannica's article , for one, has Halley's Comet in the title and Comet Halley in the article. Saros136 (talk) 07:55, 5 March 2008 (UTC)

Actually if you look closely it says "also called Comet Halley". There's a picture that interrupts the text (in my browser and font sizes at least) so it's not completely obvious that the "also called" goes with the "Comet Halley", but I'm pretty sure that's what's intended. --Trovatore (talk) 09:28, 5 March 2008 (UTC)

You're right. I got confused. Another of the Britannica articles uses Comet Halley. Saros136 (talk) 23:31, 5 March 2008 (UTC)

What I meant was that the opening sentence should say something like "Comet Halley, often called Halley's Comet..." or something like that instead of "Halleys Comet, also known as Comet Halley...". TheOtherSiguy (talk) 20:57, 5 March 2008 (UTC)

And I think you're wrong; it shouldn't. We don't blindly follow the pronouncements of organizations that decide they want to engage in language reform. Acetylene, not "ethine". --Trovatore (talk) 21:06, 5 March 2008 (UTC)

Last Observation

When was Halley's Comet last observed? Can it in 2008 still be observed with very large telescopes? Is the Hubble Space Telescope regulary pointed to it, in order to determine its orbit? —Preceding unsigned comment added by 91.46.224.25 (talk) 19:06, 14 April 2008 (UTC)