<p>I've checked several sources. Where this term appears in dictionaries, it is translated with a definition, and not a gloss (usually if a direct translation exists in English only a gloss is given) For example <a href="https://en.wiktionary.org/wiki/mezzocielo" rel="noreferrer">https://en.wiktionary.org/wiki/mezzocielo</a> <em>intersection of the meridian of a given place with the celestial equator.</em>  </p>

<p>I conclude that English speaking astronomers have not had the benefit of single word translation of <em>mezzocielo</em>.</p>

CC BY-SA 4.0
2020-03-31T15:45:35.113Z
2020-03-31T15:45:35.113Z
James K
<p>What is the name of the point of intersection of the great circle passing through the celestial north pole P and the Zenith Z, with the celestial equator? (Point T in the figure)</p>
<p>In Italian this point is called &quot;<a href="https://it.wikipedia.org/wiki/Mezzocielo" rel="nofollow noreferrer">Mezzocielo</a>&quot; (<a href="https://translate.google.com/translate?sl=auto&amp;tl=en&amp;u=https://it.wikipedia.org/wiki/Mezzocielo" rel="nofollow noreferrer">English machine translation</a>), which translates into mid-sky, since it is located halfway between the Zenith and the horizon for an observer in Italy (<span class="math-container">$\phi \approx 40^{\circ}$</span>).
<a href="https://i.sstatic.net/H87r9.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/H87r9.png" alt="Point B in the figure" /></a></p>

CC BY-SA 4.0
2020-03-30T20:59:41.340Z
I don't believe that that point has a specific name in English.
James K
CC BY-SA 4.0
2020-03-31T15:29:55.217Z
It actually is quite an important point, since the Hour Angle (HA) is measured from it. Shouldn't we give it a name :)?
JustThinking
CC BY-SA 4.0
2020-03-31T15:39:27.467Z
"Should" is a different question.
James K
CC BY-SA 4.0
2020-03-31T16:06:45.517Z
The hour angle is really a measure of the angle between the plane of the meridian and the plane passing through the object, so it does not need to be measured along the equator. Like James K, I do not know of a single work to describe point T. The closest would be "equator culmination".
JohnHoltz
CC BY-SA 4.0
2020-03-31T16:54:02.430Z
@JohnHoltz sometimes, however, HA is defined as an arc width, rather than an angle.  In this case it is important to measure it along the celestial equator. For instance the above image is incorrect, because it shows HA measured as an arc width on the wrong parallel of declination, leading to a measurement of HA/cos(delta).
JustThinking
CC BY-SA 4.0
2020-03-31T20:42:45.933Z
*It actually is quite an important point ... shouldn't we give it a name*  I've gone over fifty years without having a name for this point (and many other scientific/mathematical things).  It's just not practical to name everything someone finds important and then expect people to memorize all these names (which are essentially random labels in multiple languages).  In astronomy it's a particular issue as there are far more objects that someone somewhere finds interesting than we could possibly ever name usefully.
StephenG - Help Ukraine
CC BY-SA 4.0
2020-03-31T23:07:09.320Z
The declination is an angle between two lines, such as BOX, but the hour angle is not the angle UOX. So H*cos(delta) is not a factor. Even if the arrow showing the hour angle is drawn from U to X (or near the zenith as in this diagram), it should be interpreted as the angle between the planes TOP and BOP.
JohnHoltz
CC BY-SA 4.0
2020-12-28T13:51:54.587Z
There's a related point called the [midheaven](https://en.wikipedia.org/wiki/Midheaven) (abbreviated as MC from Latin Medium Coeli), which is the intersection of the meridian with the ecliptic (not the celestial equator).
PM 2Ring
<coordinate><terminology><naming>
Astronomical Term *Mezzocielo*
JustThinking
# Astronomical Term *Mezzocielo*

(Asked by: username_0 on 2020-03-30)

What is the name of the point of intersection of the great circle passing through the celestial north pole P and the Zenith Z, with the celestial equator? (Point T in the figure)

In Italian this point is called "[Mezzocielo](https://it.wikipedia.org/wiki/Mezzocielo)" ([English machine translation](https://translate.google.com/translate?sl=auto&tl=en&u=https://it.wikipedia.org/wiki/Mezzocielo)), which translates into mid-sky, since it is located halfway between the Zenith and the horizon for an observer in Italy ($\phi \approx 40^{\circ}$).
[![Point B in the figure](https://i.sstatic.net/H87r9.png)](https://i.sstatic.net/H87r9.png)

**Tags:** coordinate, terminology, naming
> **Comments:**
> **username_1**: I don't believe that that point has a specific name in English.  
> **username_0**: It actually is quite an important point, since the Hour Angle (HA) is measured from it. Shouldn't we give it a name :)?  
> **username_1**: "Should" is a different question.  
> **username_2**: The hour angle is really a measure of the angle between the plane of the meridian and the plane passing through the object, so it does not need to be measured along the equator. Like James K, I do not know of a single work to describe point T. The closest would be "equator culmination".  
> **username_0**: @JohnHoltz sometimes, however, HA is defined as an arc width, rather than an angle.  In this case it is important to measure it along the celestial equator. For instance the above image is incorrect, because it shows HA measured as an arc width on the wrong parallel of declination, leading to a measurement of HA/cos(delta).  
> **username_3**: *It actually is quite an important point ... shouldn't we give it a name*  I've gone over fifty years without having a name for this point (and many other scientific/mathematical things).  It's just not practical to name everything someone finds important and then expect people to memorize all these names (which are essentially random labels in multiple languages).  In astronomy it's a particular issue as there are far more objects that someone somewhere finds interesting than we could possibly ever name usefully.  
> **username_2**: The declination is an angle between two lines, such as BOX, but the hour angle is not the angle UOX. So H*cos(delta) is not a factor. Even if the arrow showing the hour angle is drawn from U to X (or near the zenith as in this diagram), it should be interpreted as the angle between the planes TOP and BOP.  
> **username_4**: There's a related point called the [midheaven](https://en.wikipedia.org/wiki/Midheaven) (abbreviated as MC from Latin Medium Coeli), which is the intersection of the meridian with the ecliptic (not the celestial equator).  

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## 1 answers

### Answer by username_1 on 2020-03-31. Score: 5 | Accepted answer

I've checked several sources. Where this term appears in dictionaries, it is translated with a definition, and not a gloss (usually if a direct translation exists in English only a gloss is given) For example <https://en.wiktionary.org/wiki/mezzocielo> *intersection of the meridian of a given place with the celestial equator.*

I conclude that English speaking astronomers have not had the benefit of single word translation of *mezzocielo*.


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