<h1>Dynamic daylighting</h1>
<p><a href="http://andrewmarsh.com/software/daylight-box-web/" rel="nofollow noreferrer">Dynamic Daylighting</a> is an impressive, free, online tool written by <a href="http://andrewmarsh.com/" rel="nofollow noreferrer">Andrew Marsh</a>.</p>
<blockquote>
<p>This app investigates real-time dynamic daylight analysis within a
simple rectangular room based on detailed sky distributions. The room
size, windows, external shading devices and work plane height can all
be interactively manipulated with the internal daylight distribution
updating in real time. You can add any number of windows, external
shading devices or site obstructions, and experiment with different
surface reflectances and window transmittances.</p>
</blockquote>
<p>You can specify the location of the building, resize it, rotate it and add external buildings.</p>
<p><a href="https://i.sstatic.net/7Rf5B.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/7Rf5B.jpg" alt="screenshot" /></a></p>
<p>You can also download weather data, import it and launch a simulation for a whole year, which outputs hours of sun per year.</p>
<h1>Other tools</h1>
<p>You might also be interested in other apps written by Andrew, e.g.:</p>
<ul>
<li><a href="http://andrewmarsh.com/software/sunpath3d-web/" rel="nofollow noreferrer">3D Sun-Path</a>
<a href="https://i.sstatic.net/Yrykg.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Yrykg.jpg" alt="enter image description here" /></a></li>
</ul>
<p>and more in accordance with AstronomyStackExchange:</p>
<ul>
<li><a href="http://andrewmarsh.com/software/web-earthsun/" rel="nofollow noreferrer">Earth and Sun</a>
<a href="https://i.sstatic.net/LD812.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/LD812.jpg" alt="enter image description here" /></a></li>
</ul>

CC BY-SA 4.0
2021-03-07T17:59:18.877Z
2021-03-07T17:59:18.877Z
Eric Duminil
<p>Merriam-Webster defines <a href="https://www.merriam-webster.com/dictionary/diurnal%20arc" rel="noreferrer">diurnal arc</a>:</p>
<blockquote>
<p>the portion of the diurnal circle of a celestial body that is above the observer's horizon</p>
</blockquote>
<p>and <a href="https://www.merriam-webster.com/dictionary/diurnal%20circle" rel="noreferrer">diurnal circle</a>:</p>
<blockquote>
<p>the apparent circle or parallel of <a href="https://en.wikipedia.org/wiki/Declination" rel="noreferrer">declination</a> described by a celestial body in consequence of the earth's rotation</p>
</blockquote>
<p>The <a href="https://www.esrl.noaa.gov/gmd/grad/solcalc/" rel="noreferrer">NOAA Solar Calculator</a> does not implement the exact feature in question but can show the Sun's <a href="https://en.wikipedia.org/wiki/Azimuth" rel="noreferrer">azimuth</a> for any given location, date, and time.</p>

CC BY-SA 4.0
2021-03-06T16:49:55.030Z
2021-03-06T16:49:55.030Z
Mike G
<p>The apparent path of the Sun in the sky is called just that, 'apparent path of the sun'. Sure enough it varies with location and with time-of-year, especially the further you live from the equator. The Sun will rise and set exactly East and West on the equinoxes, and be highest in the sky at noon in Summer on mid-summer (21th June or 21st December) and lowest at noon at winter solistice. Between rise and set for any day you can approximate the <a href="https://en.wikipedia.org/wiki/Position_of_the_Sun#Declination_of_the_Sun_as_seen_from_Earth" rel="noreferrer">apparent path's height</a> (or <a href="https://en.wikipedia.org/wiki/Solar_zenith_angle" rel="noreferrer">zenith angle</a>) quite well with a parabola (a sine curve is better).</p>
<p><a href="https://app.photoephemeris.com/" rel="noreferrer">The photographer's ephemeris</a> is a nice tool which visualizes the Sun's and Moon's path for any chosen location and date and which can also take into account the topography. Registration is free.</p>

CC BY-SA 4.0
2021-03-06T09:59:28.023Z
2021-03-06T10:13:46.577Z
2021-03-06T10:13:46.577Z
planetmaker
<p>&quot;Path of the sun&quot; would seem to be a sufficient term.</p>
<p>The <a href="https://www.suncalc.org/#/38.3419,-98.0867,3.9999884584858387/2021.03.06/12:43/1/3" rel="nofollow noreferrer">SunCalc</a> app can give you want you need.  It can tell you the position of the sun in the sky at any time and on any date  So it can tell you that on March the 6th in Lyons KS, the sun rises at 6:56, on a bearing of 096 (about 4 degrees south of east) reaches a maximum height at 12:43, when it is due south and an elevation angle of 46 degrees above the horizon, and sets at 18:31.</p>

CC BY-SA 4.0
2021-03-06T10:41:11.123Z
2021-03-06T10:41:11.123Z
James K
<p>I want to buy a house and I'm asking myself what quantity of daylight the various sides of the house receive.</p>
<p>I know the house is roughly oriented in the east-west direction.</p>
<p>But I'd like to know the exact apparent path of the Sun around the house depending on seasons, with (ideally) the elevation angle of the Sun.</p>
<p>Is there a technical term for &quot;the apparent path of the sun at a given point of the Earth, at a given time of the year&quot;?</p>
<p>Also, is there an online tool that allows one to visualize this path on a map?</p>

CC BY-SA 4.0
2021-03-06T22:36:02.300Z
Unless you're comparing houses that are very, very far apart, the main difference in sunlight is going to have to do more with the local topography. One hill or tree in the right place can make a huge difference.
user3067860
CC BY-SA 4.0
2021-03-07T22:54:33.903Z
"sunward"; cf. [deasil](https://en.wiktionary.org/wiki/deasil#English)
Luke Sawczak
<the-sun><light><software>
Is there a term for "path of the Sun at a given point of the Earth"
Floridus Floridi
# Is there a term for "path of the Sun at a given point of the Earth"

(Asked by: username_0 on 2021-03-06)

I want to buy a house and I'm asking myself what quantity of daylight the various sides of the house receive.

I know the house is roughly oriented in the east-west direction.

But I'd like to know the exact apparent path of the Sun around the house depending on seasons, with (ideally) the elevation angle of the Sun.

Is there a technical term for "the apparent path of the sun at a given point of the Earth, at a given time of the year"?

Also, is there an online tool that allows one to visualize this path on a map?

**Tags:** the-sun, light, software

> **Comments:**
> **username_1**: Unless you're comparing houses that are very, very far apart, the main difference in sunlight is going to have to do more with the local topography. One hill or tree in the right place can make a huge difference.  
> **username_2**: "sunward"; cf. [deasil](https://en.wiktionary.org/wiki/deasil#English)  

---

## 4 answers

### Answer by username_3 on 2021-03-07. Score: 3 | Accepted answer

# Dynamic daylighting

[Dynamic Daylighting](http://andrewmarsh.com/software/daylight-box-web/) is an impressive, free, online tool written by [Andrew Marsh](http://andrewmarsh.com/).

> This app investigates real-time dynamic daylight analysis within a
> simple rectangular room based on detailed sky distributions. The room
> size, windows, external shading devices and work plane height can all
> be interactively manipulated with the internal daylight distribution
> updating in real time. You can add any number of windows, external
> shading devices or site obstructions, and experiment with different
> surface reflectances and window transmittances.

You can specify the location of the building, resize it, rotate it and add external buildings.

[![screenshot](https://i.sstatic.net/7Rf5B.jpg)](https://i.sstatic.net/7Rf5B.jpg)

You can also download weather data, import it and launch a simulation for a whole year, which outputs hours of sun per year.

# Other tools

You might also be interested in other apps written by Andrew, e.g.:

* [3D Sun-Path](http://andrewmarsh.com/software/sunpath3d-web/)
  [![enter image description here](https://i.sstatic.net/Yrykg.jpg)](https://i.sstatic.net/Yrykg.jpg)

and more in accordance with AstronomyStackExchange:

* [Earth and Sun](http://andrewmarsh.com/software/web-earthsun/)
  [![enter image description here](https://i.sstatic.net/LD812.jpg)](https://i.sstatic.net/LD812.jpg)


---

### Answer by username_4 on 2021-03-06. Score: 7

Merriam-Webster defines [diurnal arc](https://www.merriam-webster.com/dictionary/diurnal%20arc):

> the portion of the diurnal circle of a celestial body that is above the observer's horizon

and [diurnal circle](https://www.merriam-webster.com/dictionary/diurnal%20circle):

> the apparent circle or parallel of [declination](https://en.wikipedia.org/wiki/Declination) described by a celestial body in consequence of the earth's rotation

The [NOAA Solar Calculator](https://www.esrl.noaa.gov/gmd/grad/solcalc/) does not implement the exact feature in question but can show the Sun's [azimuth](https://en.wikipedia.org/wiki/Azimuth) for any given location, date, and time.


---

### Answer by username_5 on 2021-03-06. Score: 5

The apparent path of the Sun in the sky is called just that, 'apparent path of the sun'. Sure enough it varies with location and with time-of-year, especially the further you live from the equator. The Sun will rise and set exactly East and West on the equinoxes, and be highest in the sky at noon in Summer on mid-summer (21th June or 21st December) and lowest at noon at winter solistice. Between rise and set for any day you can approximate the [apparent path's height](https://en.wikipedia.org/wiki/Position_of_the_Sun#Declination_of_the_Sun_as_seen_from_Earth) (or [zenith angle](https://en.wikipedia.org/wiki/Solar_zenith_angle)) quite well with a parabola (a sine curve is better).

[The photographer's ephemeris](https://app.photoephemeris.com/) is a nice tool which visualizes the Sun's and Moon's path for any chosen location and date and which can also take into account the topography. Registration is free.


---

### Answer by username_6 on 2021-03-06. Score: 3

"Path of the sun" would seem to be a sufficient term.

The [SunCalc](https://www.suncalc.org/#/38.3419,-98.0867,3.9999884584858387/2021.03.06/12:43/1/3) app can give you want you need. It can tell you the position of the sun in the sky at any time and on any date So it can tell you that on March the 6th in Lyons KS, the sun rises at 6:56, on a bearing of 096 (about 4 degrees south of east) reaches a maximum height at 12:43, when it is due south and an elevation angle of 46 degrees above the horizon, and sets at 18:31.


---

