<p>Guy Ottewell makes a comprehensive <a href="https://www.universalworkshop.com/astronomical-calendar-any-year/" rel="nofollow noreferrer">Astronomical Calendar</a> each year.
From the 2020 edition:</p>

<pre><code>8959.117 Apr 19 SUN 15    Sun enters the astrological sign Taurus, i.e. its
                          longitude is 30°
</code></pre>

<p>That's 2020-04-19 ~15h UT, which falls on April 20 in far eastern terrestrial longitudes and April 19 everywhere else.
The next such event is 1 tropical year (365d 5h 49m) later.</p>

<pre><code>8983.315 May 13 Wed 20    Sun enters Taurus, at longitude 53.48° on the eclip-
                          tic
</code></pre>

<p>The Sun enters the <a href="https://commons.wikimedia.org/wiki/File:Taurus_IAU.svg" rel="nofollow noreferrer">constellation</a> at 2020-05-13 ~20h UT, which falls on May 14 in Asia, Australia, etc., and May 13 everywhere else.
This event recurs 1 sidereal year (365d 6h 9m) later.
In that time, the ecliptic longitude of the constellation boundary increases by 0.014&deg;.</p>

CC BY-SA 4.0
2020-04-09T22:41:11.623Z
`+1` There's that word again! [So, what, exactly, is a tropical period?](https://astronomy.stackexchange.com/q/35553/7982)
uhoh
CC BY-SA 4.0
2020-04-09T23:34:01.407Z
Well, I see that not only I confused... According to this table is on "April 20, 2019: Sun enters sign Taurus (30°)" - https://earthsky.org/human-world/suns-entry-into-each-sign
Reckless Glacier
CC BY-SA 4.0
2020-04-09T23:48:13.750Z
That was 2019. Ottewell's calendar for that year lists the event at 2019-04-20 9h UT. Feb 2020 had a leap day, so the Apr 2020 event occurs 18 hours earlier instead of 6 hours later.
Mike G
CC BY-SA 4.0
2020-04-10T00:03:52.217Z
Thank you very much. You answered my question.
Reckless Glacier
CC BY-SA 4.0
2020-04-10T03:11:16.540Z
Another reference: http://www.abc2home.ru/znaki_zodiaka/constellations/zodiac-signs-sun-2020.html
Reckless Glacier
CC BY-SA 4.0
2020-04-09T19:58:31.920Z
2020-04-09T19:58:31.920Z
Mike G
<p>If <a href="https://en.wikipedia.org/wiki/March_equinox" rel="nofollow noreferrer">March equinox</a> is on 20th March (see the table in the link), according to it, when is the time that the sun enters Taurus? Is it on April 19 or April 20? </p>

CC BY-SA 4.0
2020-04-09T18:49:41.443Z
Looking at Stellarium: Looks like the Sun crosses into Taurus this year around May 13-14.
notovny
CC BY-SA 4.0
2020-04-09T19:16:13.373Z
And from Guide9, about 18.00 UT on 13 May is when its leading edge hits the boundary between Aries and Taurus - at least for the astronomical constellations.
Dr Chuck
CC BY-SA 4.0
2020-04-09T21:08:21.890Z
I'm voting to close this question as off-topic because astrology
James K
CC BY-SA 4.0
2020-04-09T21:36:38.870Z
@James K What astrology in that?  It is pure astronomy! It is the second time you call my question astrology while I'm interested in astrology at all,  but I'm interested in the history of the astronomy.
Reckless Glacier
CC BY-SA 4.0
2020-04-09T22:21:19.143Z
James K has a point, the Sun's λ=30° date is of little interest outside astrology. If there's an astronomical purpose, you need to show what it is, not just claim that there is one.
Mike G
CC BY-SA 4.0
2020-04-09T22:31:53.647Z
My purpose is to understand the differences between the 'previous' **astronomy** to the current one.  Data of astronomy out of date is still astronomy and still studied in astronomy departments at any respected university.
Reckless Glacier
CC BY-SA 4.0
2020-04-09T23:10:31.433Z
Sorry, "it's about history" is not very convincing when the question is about the present year.
Mike G
CC BY-SA 4.0
2020-04-09T23:22:35.213Z
Sorry, what's wrong if I want to learn the history of the astronomy according the present? I compare the methods. It's pure astronomy, nothing with astrology. If you suspect me that it isn't my purpose, so then what it can be? If you insist that I'm astrologist  or believe in this nonsense, I give up.
Reckless Glacier
CC BY-SA 4.0
2020-04-10T21:52:09.983Z
*I want to learn the history of the astronomy according the present*  I have no idea what that means, but asking for a *future* date for something to happen seems quite unconnected to history.  There is, BTW, a [History of Science and Mathematics SE](https://hsm.stackexchange.com/).
StephenG - Help Ukraine
CC BY-SA 4.0
2020-04-10T23:35:52.987Z
If you learnt about something that it's out of date, and you are going to make an experiment about it next month,  in order to understand it historically what was wrong with that, so to your opinion it is unconnected to history?  Thank you for the useful site that I didn't know.
Reckless Glacier
CC BY-SA 4.0
2020-04-11T08:45:37.420Z
You could use stellarium to figure this kind of thing out.
usernumber
<zodiac>
Based on March equinox, when is the time that the sun enters Taurus?
Reckless Glacier
# Based on March equinox, when is the time that the sun enters Taurus?

(Asked by: username_0 on 2020-04-09)

If [March equinox](https://en.wikipedia.org/wiki/March_equinox) is on 20th March (see the table in the link), according to it, when is the time that the sun enters Taurus? Is it on April 19 or April 20?

**Tags:** zodiac
> **Comments:**
> **username_1**: Looking at Stellarium: Looks like the Sun crosses into Taurus this year around May 13-14.  
> **username_2**: And from Guide9, about 18.00 UT on 13 May is when its leading edge hits the boundary between Aries and Taurus - at least for the astronomical constellations.  
> **username_3**: I'm voting to close this question as off-topic because astrology  
> **username_0**: @James K What astrology in that?  It is pure astronomy! It is the second time you call my question astrology while I'm interested in astrology at all,  but I'm interested in the history of the astronomy.  
> **username_4**: James K has a point, the Sun's λ=30° date is of little interest outside astrology. If there's an astronomical purpose, you need to show what it is, not just claim that there is one.  
> **username_0**: My purpose is to understand the differences between the 'previous' **astronomy** to the current one.  Data of astronomy out of date is still astronomy and still studied in astronomy departments at any respected university.  
> **username_4**: Sorry, "it's about history" is not very convincing when the question is about the present year.  
> **username_0**: Sorry, what's wrong if I want to learn the history of the astronomy according the present? I compare the methods. It's pure astronomy, nothing with astrology. If you suspect me that it isn't my purpose, so then what it can be? If you insist that I'm astrologist  or believe in this nonsense, I give up.  
> **username_5**: *I want to learn the history of the astronomy according the present*  I have no idea what that means, but asking for a *future* date for something to happen seems quite unconnected to history.  There is, BTW, a [History of Science and Mathematics SE](https://hsm.stackexchange.com/).  
> **username_0**: If you learnt about something that it's out of date, and you are going to make an experiment about it next month,  in order to understand it historically what was wrong with that, so to your opinion it is unconnected to history?  Thank you for the useful site that I didn't know.  
> **username_6**: You could use stellarium to figure this kind of thing out.  

---

## 1 answers

### Answer by username_4 on 2020-04-09. Score: 3 | Accepted answer

Guy Ottewell makes a comprehensive Astronomical Calendar each year.
From the 2020 edition:
8959.117 Apr 19 SUN 15    Sun enters the astrological sign Taurus, i.e. its
                          longitude is 30°

That's 2020-04-19 ~15h UT, which falls on April 20 in far eastern terrestrial longitudes and April 19 everywhere else.
The next such event is 1 tropical year (365d 5h 49m) later.
8983.315 May 13 Wed 20    Sun enters Taurus, at longitude 53.48° on the eclip-
                          tic

The Sun enters the constellation at 2020-05-13 ~20h UT, which falls on May 14 in Asia, Australia, etc., and May 13 everywhere else.
This event recurs 1 sidereal year (365d 6h 9m) later.
In that time, the ecliptic longitude of the constellation boundary increases by 0.014°.

> **Comments:**
> **username_7**: `+1` There's that word again! [So, what, exactly, is a tropical period?](https://astronomy.stackexchange.com/q/35553/7982)  
> **username_0**: Well, I see that not only I confused... According to this table is on "April 20, 2019: Sun enters sign Taurus (30°)" - https://earthsky.org/human-world/suns-entry-into-each-sign  
> **username_4**: That was 2019. Ottewell's calendar for that year lists the event at 2019-04-20 9h UT. Feb 2020 had a leap day, so the Apr 2020 event occurs 18 hours earlier instead of 6 hours later.  
> **username_0**: Thank you very much. You answered my question.  
> **username_0**: Another reference: http://www.abc2home.ru/znaki_zodiaka/constellations/zodiac-signs-sun-2020.html  

---

