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How do I find some of the constellations of the zodiac without remembering their locations on the sky?

I think it should be quite simple if you are located in the northern hemisphere and you know 1) which astrological sign it is right now (this month) 2) where the sun set 3) the number of hours left until sunrise 4) the order of the constellations in the circle of the zodiac: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces.

Straight forward logic says that it is enough to make calculations in order to understand where they should be, but I can't find any such rule on the internet. Maybe it is not so simple. Have you seen such a rule?

Alphecca
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Roman Pokrovskij
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  • Note that when astrology says the Sun is in Aries at the vernal equinox, it's wrong by almost a full sign: the vernal equinox currently points to Pisces, and will in a few hundred years point to somewhere in Aquarius. This is the precession of the equinoxes. And if you work out which constellation the Sun is actually in, that's not much help at night. You also need to know where the ecliptic lies, and this changes from season to season. Too complicated! There are plenty of free apps that will give you a map of the constellations as you see them from your location. – Chappo Hasn't Forgotten Dec 14 '18 at 22:35
  • I know about apps. But trying to understand how it works by itself is better. – Roman Pokrovskij Dec 14 '18 at 22:38
  • It is usually not complex to understand where is ecliptic since you remember where was point of sunset and there is usually a planet like Mars on a sky. So somewhere on this halfcircle. Isn't it? – Roman Pokrovskij Dec 14 '18 at 22:40
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    It's only (roughly) a half-circle in high summer; at other times it's a smaller arc. But another problem is that astrology divides the ecliptic into 12 equal divisions, whereas the constellations themselves aren't equally spaced along the zodiac. Your method will certainly help you understand the sky better, primarily because you will have to work quite hard to subtract precessional drift, estimate the ecliptic's arc, and guess what part of the constellation intersects the ecliptic. – Chappo Hasn't Forgotten Dec 14 '18 at 22:50
  • Because it is a great circle, half of the ecliptic is visible at all times. Likewise, half of the celestial equator is always above the horizon. – JohnHoltz Dec 15 '18 at 01:40
  • @JohnHoltz ah, I see where my error is - my apologies. I'm confusing the Sun's diurnal path across the observer's sky with its annual path on the celestial sphere (along the ecliptic). At midwinter the Sun remains below the horizon but the other half of the ecliptic is above the horizon. I'll delete my comments... – Chappo Hasn't Forgotten Dec 16 '18 at 21:49
  • @JohnHoltz I can't understand how it could be valid together 1) stars never set 2) the ecliptic is visible from 0 hours to 12 hours. If stars never set where could gone the eclipitc ? If you see Areas 24h means you see Areas 24h - and the ecliptic can't be in other concelation on the pole. – Roman Pokrovskij Dec 16 '18 at 22:17
  • Hi @RomanPokrovskij. My comment (which I have deleted to clean up the thread) should have made a distinction between the coordinates of right ascension (RA) which is measured in hours and time of day (in hours). The portion of the ecliptic visible from the N Pole is between 0 hrs RA through 12 hrs RA (Pisces through Virgo). That section is visible 24 hours a day. The portion of the ecliptic from 12 hrs RA through 24 hrs RA (Virgo through Aquarius) is not visible from the pole at any time of the day/night/year. – JohnHoltz Dec 17 '18 at 17:28

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This is far too complicated. You can find any asterism in the sky far more simply by remembering its shape and its position relative to other (perhaps brighter) constellations.

For the Zodiac constellations, they are all in a band that (in the Northern hemisphere) goes from East through South, to West. In the winter, that band will be high is the sky. In summer it will be low.

And then you learn the sky.

In winter you first learn Orion and from there you can find your way to Gemini, the V of the Hyades in Taurus. Cancer is dim (but has that nice cluster), but next in line, Leo, is nice and bright.

If you want to find out what is actually visible right now, go outside! If you want to check on the location or visibility of a particular constellation right now, use planetarium software.

You don't need to calculate anything.

James K
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  • Usually there is not enough visibility (especially near horizon) so its look like anyway I would have only directions :) Also it would simplify things to know which concelations are visible right now (not all of them visible half of them are hidden by horizon, as I understand). – Roman Pokrovskij Dec 14 '18 at 22:32
  • I have never thought that winter time when sun is low the same time at night the ecliptic is high. Thank you. – Roman Pokrovskij Dec 14 '18 at 22:41