Comments on: Does the Sun look smaller to you? http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/ I am an astronomer, writer, and skeptic. I likes reality the way it is, and I aims to keep it that way. My real name is Phil Plait, and I run the Bad Astronomy blog. Thu, 04 Dec 2008 08:23:46 +0000 http://wordpress.org/?v=2.3.1 By: ¿Te pareció que el sol era más pequeño ayer? Era el afelio | Proyecto web http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-123264 ¿Te pareció que el sol era más pequeño ayer? Era el afelio | Proyecto web Sun, 05 Oct 2008 01:52:55 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-123264 [...] y como explican en Bad Astronomy, la diferencia entre el punto más alejado (Afelio) y el más cercano (Perihelio) es de unos cuatro [...] […] y como explican en Bad Astronomy, la diferencia entre el punto más alejado (Afelio) y el más cercano (Perihelio) es de unos cuatro […]

]]> By: Doug Riemer http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-106051 Doug Riemer Sun, 27 Jul 2008 14:37:02 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-106051 The statement, "Of course precession also means that astrology is fundamentally wrong" repeated by several bloggers is also "fundamentally wrong," for it applies only to Western (tropical) astrology, which is based upon the spring equinox. Vedic Astrology (from India) uses the sidereal, "star based" zodiac which does maintain the connection with the actual astronomical positions. And, this is not some minor branch of astrology but is found both in India and increasingly in the West. Science is only well served when all facts are considered. The statement, “Of course precession also means that astrology is fundamentally wrong” repeated by several bloggers is also “fundamentally wrong,” for it applies only to Western (tropical) astrology, which is based upon the spring equinox.

Vedic Astrology (from India) uses the sidereal, “star based” zodiac which does maintain the connection with the actual astronomical positions. And, this is not some minor branch of astrology but is found both in India and increasingly in the West.

Science is only well served when all facts are considered.

]]> By: Irishman http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-97271 Irishman Mon, 07 Jul 2008 20:44:23 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-97271 Blaidd Drwg, DUDE, don't throw DR WHO spoilers in non-DR WHO threads. Jeeze, some of us haven't seen it yet, on account of it not airing here for another couple weeks. Blaidd Drwg, DUDE, don’t throw DR WHO spoilers in non-DR WHO threads. Jeeze, some of us haven’t seen it yet, on account of it not airing here for another couple weeks.

]]> By: Tom Marking http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-97049 Tom Marking Mon, 07 Jul 2008 03:43:08 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-97049 "Oh, one more thing: the Earth precesses, that is, the axis of rotation moves like a wobbling top. It takes a long time for the wobble to make one cycle, well over 20,000 years. But this changes the timing of the seasons compared to the orbit. In a few millennia, we’ll have perihelion at the same time as northern summer, and aphelion at northern winter." The precessional period (25,765 years) of the earth's axis is not the only effect. It turns out that the perihelion point of the earth's orbit also precesses with a period of 112,000 years due to gravitational effects of the other planets in the solar system. Relative to the vernal equinox the date of perihelion cycles with a period of 21,000 years. Thus, 12500 CE would have the perihelion point aligned with the summer solstice in the northern hemisphere, not the 15000 CE mentioned. http://en.wikipedia.org/wiki/Precession_%28astronomy%29#Anomalistic_precession “Oh, one more thing: the Earth precesses, that is, the axis of rotation moves like a wobbling top. It takes a long time for the wobble to make one cycle, well over 20,000 years. But this changes the timing of the seasons compared to the orbit. In a few millennia, we’ll have perihelion at the same time as northern summer, and aphelion at northern winter.”

The precessional period (25,765 years) of the earth’s axis is not the only effect. It turns out that the perihelion point of the earth’s orbit also precesses with a period of 112,000 years due to gravitational effects of the other planets in the solar system. Relative to the vernal equinox the date of perihelion cycles with a period of 21,000 years. Thus, 12500 CE would have the perihelion point aligned with the summer solstice in the northern hemisphere, not the 15000 CE mentioned.

http://en.wikipedia.org/wiki/Precession_%28astronomy%29#Anomalistic_precession

]]> By: Es sol esta mas lejos en el AFELIO | Entrando en mi mundo... http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96911 Es sol esta mas lejos en el AFELIO | Entrando en mi mundo... Sun, 06 Jul 2008 15:57:32 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96911 [...] y como explican en Bad Astronomy, la diferencia entre el punto más alejado (Afelio) y el más cercano (Perihelio) es de unos cuatro [...] […] y como explican en Bad Astronomy, la diferencia entre el punto más alejado (Afelio) y el más cercano (Perihelio) es de unos cuatro […]

]]> By: Blaidd Drwg http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96795 Blaidd Drwg Sun, 06 Jul 2008 04:36:27 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96795 I KNEW that hand would be important! (Doctor Who). Spectacular way to end the season! But bittersweet, seeing as there will now be a hiatus of almost 2 years before we get our weekly 'Who fix' again. Craig, this forum is analogous to Dr. Plait's living room. Keep in mind it is HIS blog, he sets the ground rules. Those who follow the rules are allowed to disagree, even strenuously, provided they remain within the language rules he has set. If you wish to swear, go to PZ's site, or any of the other blogs that are not 'kid friendly'. I KNEW that hand would be important! (Doctor Who). Spectacular way to end the season! But bittersweet, seeing as there will now be a hiatus of almost 2 years before we get our weekly ‘Who fix’ again.

Craig, this forum is analogous to Dr. Plait’s living room. Keep in mind it is HIS blog, he sets the ground rules. Those who follow the rules are allowed to disagree, even strenuously, provided they remain within the language rules he has set. If you wish to swear, go to PZ’s site, or any of the other blogs that are not ‘kid friendly’.

]]> By: Steve Cooperman http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96691 Steve Cooperman Sat, 05 Jul 2008 22:21:12 +0000 http://blogs.discovermagazine.com/badastronomy/2008/07/04/does-the-sun-look-smaller-to-you/#comment-96691 Half a precession cycle from now, we WON'T have summer in December. We follow the "tropical year", which keeps our calendar in step with the seasons. The GOOD news is that instead of seeing Orion at night in the dead of winter and freezing, we'll see it in the summer (if you discount global warming when ALL seasons will be hotter!) Half a precession cycle from now, we WON’T have summer in December. We follow the “tropical year”, which keeps our calendar in step with the seasons. The GOOD news is that instead of seeing Orion at night in the dead of winter and freezing, we’ll see it in the summer (if you discount global warming when ALL seasons will be hotter!)

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