Comments on: Top o' the orbit to ya! http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/ Wed, 21 Nov 2012 15:12:45 +0000 hourly 1 http://wordpress.org/?v=3.4.2 By: Centrifugal Forces and Trojan Horses « Galileo's Pendulum http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295956 Centrifugal Forces and Trojan Horses « Galileo's Pendulum Wed, 17 Aug 2011 18:17:27 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295956 [...] is moving. At the farthest point from the Sun where the force of gravity is weakest (the aphelion, which was a little over a month ago), Earth is moving more slowly and feels a smaller centrifugal force. At the closest point (the [...] [...] is moving. At the farthest point from the Sun where the force of gravity is weakest (the aphelion, which was a little over a month ago), Earth is moving more slowly and feels a smaller centrifugal force. At the closest point (the [...]

]]> By: Neil Haggath http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295955 Neil Haggath Tue, 12 Jul 2011 21:01:11 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295955 #50 Finlay et al: "App-helion" is correct. The P and H are definitely <i>not</i> pronounced as an F; they are two separate consonants, belonging to two separate syllables. The "ap" is a separate syllable, as is obvious if you consider the composition of the word. The opposite term, for the closest point in the Earth's orbit, is "perihelion". "Helion" comes from Helios, the Greek word for the Sun, "peri" and "ap" are prefixes appended to it. Similarly, the closest and furthest points of the Moon's orbit around the Earth are called perigee and apogee; for the orbit of a satellite of Jupiter, the words are perijove and apojove; for the orbit of the secondary around the primary in a binary star system, they are periastron and apastron. There are even a pair of generic words - periapsis and apoapsis - which can be applied to any orbit. So we see that "ap" is a prefix appended to a whole range of words; so the pronunciation is "app-helion". QED. #50 Finlay et al:
“App-helion” is correct. The P and H are definitely not pronounced as an F; they are two separate consonants, belonging to two separate syllables. The “ap” is a separate syllable, as is obvious if you consider the composition of the word.
The opposite term, for the closest point in the Earth’s orbit, is “perihelion”. “Helion” comes from Helios, the Greek word for the Sun, “peri” and “ap” are prefixes appended to it. Similarly, the closest and furthest points of the Moon’s orbit around the Earth are called perigee and apogee; for the orbit of a satellite of Jupiter, the words are perijove and apojove; for the orbit of the secondary around the primary in a binary star system, they are periastron and apastron. There are even a pair of generic words – periapsis and apoapsis – which can be applied to any orbit.
So we see that “ap” is a prefix appended to a whole range of words; so the pronunciation is “app-helion”. QED.

]]> By: Finlay http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295954 Finlay Thu, 07 Jul 2011 23:02:34 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295954 >>>I pronounce it app-HEEL-eeyun, if you care. I recently read the wikipedia article that said it should be pronounced like afelion. I now feel less alone for having always pronounced it ap-helion like you. Hooray! >>>I pronounce it app-HEEL-eeyun, if you care.
I recently read the wikipedia article that said it should be pronounced like afelion. I now feel less alone for having always pronounced it ap-helion like you. Hooray!

]]> By: Neil Haggath http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295953 Neil Haggath Wed, 06 Jul 2011 11:44:08 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295953 #47 Scarlet: Please, <i>please</i> tell me that was a joke...! In a recent UK survey into education standards, one of the "general knowledge" questions which a sample of adults were asked was, "Does the Earth go around the Sun, or the Sun around the Earth?" The number who answered correctly was... wait for this... <i>67%</i>!!!!! 19% actually got it wrong, and 14% said they didn't know! Head, meet wall. #47 Scarlet:
Please, please tell me that was a joke…!

In a recent UK survey into education standards, one of the “general knowledge” questions which a sample of adults were asked was, “Does the Earth go around the Sun, or the Sun around the Earth?” The number who answered correctly was… wait for this… 67%!!!!! 19% actually got it wrong, and 14% said they didn’t know!
Head, meet wall.

]]> By: hhEb09'1 http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295952 hhEb09'1 Wed, 06 Jul 2011 01:58:43 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295952 @Nigel That sentence is exactly correct, by itself. If there were no other change but precession, the dates would change, because the precession has caused us to use a calendar that is not tied to the stars. @Nigel
That sentence is exactly correct, by itself. If there were no other change but precession, the dates would change, because the precession has caused us to use a calendar that is not tied to the stars.

]]> By: Scarlet http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295951 Scarlet Wed, 06 Jul 2011 00:31:29 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295951 @Neil Haggath: Yes, that is rather disheartening! Just as sad is an experience I once had in an introductory college astronomy class. After completing the unit on the Sun and discussing the telescopes on campus, one student inquired, "So, how do you take pictures of it? At night, when it's far away?" @Neil Haggath: Yes, that is rather disheartening! Just as sad is an experience I once had in an introductory college astronomy class. After completing the unit on the Sun and discussing the telescopes on campus, one student inquired, “So, how do you take pictures of it? At night, when it’s far away?”

]]> By: TheMathSkeptic http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295950 TheMathSkeptic Tue, 05 Jul 2011 14:40:48 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295950 39. Mike Says: July 5th, 2011 at 5:33 am Astrology is more than 2200 years old, which means it’s just over one constellation off by now. Somehow that doesn’t seem to bother astrologers. ------ Apparently you missed the horoscopes in The Onion from earlier this year when Ophiuchus was being discussed as the "13th sign": http://www.theonion.com/articles/your-horoscopes-week-of-january-18-2011,18855/ 39. Mike Says:
July 5th, 2011 at 5:33 am
Astrology is more than 2200 years old, which means it’s just over one constellation off by now. Somehow that doesn’t seem to bother astrologers.
——
Apparently you missed the horoscopes in The Onion from earlier this year when Ophiuchus was being discussed as the “13th sign”: http://www.theonion.com/articles/your-horoscopes-week-of-january-18-2011,18855/

]]> By: Nigel Depledge http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295949 Nigel Depledge Tue, 05 Jul 2011 14:35:41 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295949 @ Mike (42) - Yes, it looks like you're right about those numbers. The wikipedia page I found seems to have got its figures confused. However, that does not change that your earlier post (27) seemed to conflate two of the different types of precession. I refer in particular to this sentence: <blockquote>However the Earth precesses (the north pole wobbles around the perpendicular to our orbit once every 26,000 years) so the date of the aphelion will change.</blockquote> This is what I initially thought wasn't right. Then I found the wiki page on Apsis and got a different set of numbers from yours as well. @ Mike (42) -
Yes, it looks like you’re right about those numbers. The wikipedia page I found seems to have got its figures confused.

However, that does not change that your earlier post (27) seemed to conflate two of the different types of precession. I refer in particular to this sentence:

However the Earth precesses (the north pole wobbles around the perpendicular to our orbit once every 26,000 years) so the date of the aphelion will change.

This is what I initially thought wasn’t right. Then I found the wiki page on Apsis and got a different set of numbers from yours as well.

]]> By: Makoto http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295948 Makoto Tue, 05 Jul 2011 13:56:56 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295948 37. Messier Tidy Upper: "So the tallest humans – the basketballers and circus giants – that are 7 or 8 feet high are going to be in a lot of trouble when they jump then? Oh & mountaineers and divers. What .. The ..!!! *Facepalm*" Exactly.. exactly. It really makes one wonder about people sometimes, doesn't it? 37. Messier Tidy Upper:
“So the tallest humans – the basketballers and circus giants – that are 7 or 8 feet high are
going to be in a lot of trouble when they jump then? Oh & mountaineers and divers. What .. The ..!!! *Facepalm*”

Exactly.. exactly. It really makes one wonder about people sometimes, doesn’t it?

]]> By: Jesse http://blogs.discovermagazine.com/badastronomy/2011/07/04/top-o-the-orbit-to-ya/#comment-295947 Jesse Tue, 05 Jul 2011 12:56:27 +0000 http://blogs.discovermagazine.com/badastronomy/?p=34119#comment-295947 And now for something completely different. When greeting your fellow astronomers today, use the old hippy standby: "Far out!" And now for something completely different.

When greeting your fellow astronomers today, use the old hippy standby:
“Far out!”

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