Observations

The daily motion of the Sun throughout the year as seen from the southern hemisphere

Motion Sun solstices equinoxes diagram by Nick Lomb

An animated diagram showing the daily motion of the Sun at the turning points of the year, the summer and winter solstices and the spring and autumn equinoxes, as seen from southern latitudes at places such as Sydney, Melbourne or Perth. Diagram Nick Lomb

Jim asked:

Would like to ask a question regarding the direction of Sun rise and set during Summer here in Perth. W.A.

I have been taking compass bearings of the direction the Sun has been rising and setting during Dec here in Perth.

I have found that the Sun is rising in the South East and sets in the South West.

I would have expected that the Sun would rise in the North East and set in the North West. Obviously my reasoning is flawed and I was hoping you could explain why.

My reasoning is that the furthest South the Sun gets is 23.5 degrees latitude on the Summer Solstice (22 Dec 13). As Perth’s latitude is nearly 32 degrees it would mean that the Sun is to the North of Perth and because of this I would have expected that the sun would rise to the North of East and set to the North of West.

Thanks for considering this question.

Regards

Jim

Answer:

As can be seen in the diagram above, during each day the Sun moves in an arc that is always tilted at 32° (Perth’s latitude) to the vertical and with the highest point towards the north.

At the March (autumn) and September (spring) equinoxes the Sun rises in the east, moves toward the north and sets in the west. These are the only times in the year that the Sun rises due east and sets due west. At the highest point of the daily arc at the equinoxes the Sun is 32° (Perth’s latitude) to the north of the zenith, the point overhead.

At the June (winter) solstice the Sun rises north of east, makes a small circle towards the north and sets north of west. At the highest point of its daily arc the Sun is 55.5° (32° + 23.5° (the tilt of the Earth’s axis)) to the north of the zenith.

At the December (summer) solstice it rises south of east, makes a large circle and sets south of west. At the highest point of its daily arc the Sun is 8.5° (32° – 23.5°) to the north of the zenith.

The above calculation makes the significance of the Tropic of Capricorn obvious. At a southern latitude of 23.5° at the summer solstice the Sun is overhead. In Australia the Tropic of Capricorn passes just to the south of the city of Rockhampton.

Sunset over Balmain as seen from Sydney Observatory on 29 August 2005 photographed by Nick Lomb

The Sun setting over Balmain, as seen from Sydney Observatory, on 29 August 2005. Over the next few weeks sunset moved to the left or south and by 23 September, spring equinox, it set behind the tower near the left hand edge of the picture. Photo Nick Lomb

The yearly back and forth movement of the rising and setting Sun along the eastern and western horizons, respectively, provides a useful calendar of sorts. When the Sun sets furthest to the north it is winter, when it sets due west it is spring or autumn and when it sets at its furthest to the south it is summer.

I hope that this diagram and text have helped to clarify the daily motion of the Sun at the different seasons of the year.

96 responses to “The daily motion of the Sun throughout the year as seen from the southern hemisphere

  • I live in the USA at 30°N. The sun has always come up in the east and slightly south. It has always set in the west and slightly south. I have noticed lately that it is coming up in the east and slightly north and setting in the west and slightly north. It’s just so weird.
    Correction: I am at 35°N.

  • I have often wondered at a particular point (longitude/latitude) in time when one welcomes the sun (at sunrise) which corresponding particular point (longitude/latitude) bids farewell to the sun (at sunset).

    Is there a formula to compute this?

    I have toyed with the daylight map and have noticed though I am able to roughly estimate a corresponding point where the sun rises when I watch the sun set this does not hold true throughout the year.

    • MG, There is probably more an algorithm than a formula for determining this. The daylight maps (for example the Day and Night World Map) are projections onto a flat surface of sunlight falling on to a spherical globe. The Sun’s nadir position (the point on the ground where the Sun would be at the zenith) changes over a day and through the seasons and sunlight illuminates exactly half the globe at once, plus a bit more if we include the three twilights. Knowing all that your algorithm could determine the line along the globe at which the Sun is rising and a corresponding line at which the Sun is setting, as precisely as you desired. That sounds like a great project for a PC and Python code – wish I had time to code it up!

    • Trying to determine the point on my compass where the sun comes up over the horizon. Tomorrow being our Winter Solstice. We have clear views of the ocean from our home 600 feet above sea level. Sadly clouded today and tomorrow. We live at Lat. 30.23. Without being able to spot the sunrise, how do I calculate the point at which it rises. ???

      • Gren, Yes, it is Winter Solstice tomorrow, June 21, 2017. You could use TimeAndDate, enter your location and check the Sunrise/Sunset details where the sunrise azimuth for the Sun is given. For Coffs Harbour (near 30.3-degrees south latitude) the sunrise azimuth is 63-degrees true. To convert to a compass, or magnetic, bearing you need to correct for the magnetic declination for your area. Geoscience Australia has an online calculator that will give you this value. I looked up the declination for Coffs Harbour and get a value of 11.9-degrees (east of north). That makes the magnetic/compass azimuth of sunrise on winter solstice 2017 (June 21, 2017) 51-degrees, to the nearest degree. Weather forecasts are just that: predictions with uncertainties. It’s the actual observation that counts!

    • MG, there is a sun/solar chart that I was given when I studied architecture @25 years ago. It is specific to your latitude. I am at 42 degrees South. From the chart (which looks a little like a protractor), you can find a day and determine on that day, where the sun will rise and where it will set (these positions are the same distance but East and West relative to North). It is a very clever chart, which I unfortunately no longer have and have not been able to find again. If anyone knows where it can be found, I would love to know.

  • Thank you so much for the animated diagram. I am presently photographing a large Sydney suburb for a heritage project. Now that I understand the sun is moving North at this time of year, I realise I’ll have to start the photography much earlier to photograph South facing areas.

  • Yep the sun rise/set was further south this summer. I made a note last year of positions. I concure. With the sun rise earlier.
    Winter sun rise/set was also further north. And sunset very early.

  • The nautical almanac has priced itself out my financial reach.
    Is there a web site where I can find the Latitude/Longitude (GHA), of the sun, north or south of the Equator, for any specific day of the year, and UTC.
    I’m trying to keep the dust of my sextant.
    A short email response would be appreciated as I only found your site by chance, have written site down, but may not find it again.
    Many thanks ~Juri

    • Juri, I’m more familiar with astronomical applications than nautical ones. You could try the JPL Horizons system (introduction to it here). You could also purchase the Multiyear Interactive Computer Almanac (MICA) – more or less an equivalent to the hardcopy Astronomical Almanac. There may be an equivalent for the Nautical Almanac, but I am not aware of this. You might still have to do a few calculations to find GHA (Greenwich Hour Angle). [reply also sent via email]

  • The movement of the sun doesn’t make sense to some people until they realize that the sun is only small and rotates above the flat round earth than things will start to make sense. Don’t believe blindly what scientists tell you. Observe and learn. The sun moves and the earth stands still.

    • Jerry, “Observe and learn” is not enough. The process is Observe, Hypothesise (make an educated guess at an explanation), Test/Experiment, Record data, Analyse, Refine Hypothesis (or abandon it if wrong), Repeat. Two thousand years of this process has convinced us to abandon the flat earth hypothesis. Instead we know the Sun is 1.4 million kilometres in diameter (big!) and 150 million kilometres away. Earth is a globe and moves around the Sun. Yes, the Sun moves, but it moves around the Milky Way galaxy and it carries Earth and all the other planets along with it.

        • Chad, They have moved. You can’t detect the movement of most stars by eye but it is measurable with a telescope, camera and enough time, or with a spacecraft such as GAIA. Even a pair of binoculars and a few years of your time will show you that the star 61 Cygni is moving – and over the course of a lifetime you would be able to detect its movement with your naked eye.

  • Hi andrew,i live in sydney and i understand the pattern of the sun that you put up,my green house runs from east to west and faces south (the only way i can have it)my question is ,i watched the suns movements last year as most of my orchids a winter flowering and the was slightly ne as it went over the top,but this year it seems to be a lot further back,can this be correct or have missed calculated somewhere,thanks peter.

      • Peter, my apologies, sometimes posts slip through, particularly in busy times. I understand how your greenhouse is oriented but I’m not quite sure what you mean by ‘the [sun?] was slightly ne [north-east?] as it went over the top’. Regardless, the Sun’s motion across the sky repeats each year, on any date in any year its movement across the sky will be the same, i.e. its rise & set positions on the horizon are the same, its altitude at noon is the same, the arc across the sky is the same. It shouldn’t appear ‘further back’ in any sense. Could you have missed something?

        • My apologies to beg to differ, the sun follows the solar system very centre and the Earth’s polar motion will make the sun appear in a slightly different position each year.

          • Mick, Sure, if we include effects such as nutation, change in obliquity, continental drift and many others, some of which are cyclical, there are tiny changes in the Sun’s position from year to year. But these amount to no more than a small fraction of the Sun’s apparent diameter. For naked eye observations of the Sun with respect to a greenhouse there is no obvious change!

  • I am just wanting to know in Townsville Australia does the sun rise a little different in our winter? I have noticed of late that i am blinded by the morning sun in my kitchen which was not the case a month ago. Just wondering if it sits slightly different in the sky in winter even though we do not have day light savings. Thanks for any help.

    • Michelle, As our post points out the Sun rises at different points on the horizon depending on the time of year. Day light saving makes no difference to this. If you watch where the Sun rises over the next month (it now being just after the winter solstice) you will notice it will rise more northerly each day.

  • I am confused about why the suns path should be exactly the same during the autumn and spring solstice. In fact this seems to be an impossibility. furthermore if a person lives on the equator, why would they expect to see the sun rise and set exactly due east and due west? At these times the earth is tilted at a 23 degree angle relative to the sun. how is this possible?

    • Mark, the axis of the Earth is tilted at 23.5-degrees relative to the plane of its orbit around the Sun. However, the axis remains pointed at the same star in the sky (the north pole points towards star Polaris) and does not ‘spin around’ to point ‘over’ the Sun as the Earth orbits the Sun. A gyroscope demonstrates this constant pointing nicely – and the Earth is a big spinning gyroscope. The diagram in this post shows the situation. In the southern summer the south pole is tilted towards the Sun (left hand Earth in diagram). At the equinoxes neither pole is tilted towards the Sun (top and bottom Earths) because the axis is still pointing to the same distant star, Polaris.

  • I’ve got a question rather than a comment:
    Does the setting sun’s apparent rate of movement along the horizon
    remain constant as we move towards the solstice, or is there an acceleration as we approach each end of the cycle? Just curious. . .

    • Robert, The Sun’s rate of movement along the horizon is not constant. It is fastest near the equinoxes, i.e. as it is passing due West (for the setting Sun). The rate changes very slowly at the solstices.

  • Please comment on how the angle that the day/night line (terminator?) makes with the lines of longitude varies over the year. I live in Mackay (21degrees 8mins 28secs south latitude) and yes the bearing of sunrise by my naked eye estimate swings through about 45 degrees (solstice to solstice) over the year. The sun is south of us from about 27th November to around 16th January. I have always thought the ridicule of Queenslanders for rejecting daylight saving, and especially those in the north and west of the state, by the southern, especially metropolitan dwellers demonstrates a certain ignorance of both astronomy and the geography of Australia. Please comment more on astronomy in the low southern latitudes of north Australia. Great stuff!

    • Joan, It is probably easiest to watch an animation of the change in angle of the terminator to understand how it varies during the year. Time and Date has a good display of this. On the equinoxes the terminator will be parallel with Earth’s longitude lines, on other dates you can see it is ’tilted’. Your observation that the the Sun rises south of due East for part of the year is correct given that you are north of the Tropic of Capricorn. Inevitably, being based in Sydney, we have a certain bias to the conditions we observe daily. However, we are aware our audience is Australia wide, and beyond, so do try be inclusive where we are able to be.

  • Hi
    I live in Hobart (Tasmania) and have noticed the sun setting further south than normal. I measured the angle at sunset and was 237 deg from north. High school geography tells me the the sun moves between the Tropic of Capricorn through the Equator to the Tropic of Cancer during the year as per your animation at the top of your web page. So during the summer solstice if I was standing on the Tropic of Capricorn the sun should be setting due west or very close to it. As Hobart is approx 42 deg south, the sun I would expect to be setting on the northerly side of 270 deg west, and not 33deg further south of west.
    Can you help on this

    Regards
    Andrew

    • Andrew, Yes, the Sun does move between the Tropic of Capricorn through the Equator to the Tropic of Cancer during the year. However, an observer at any latitude will see the Sun rise (and set) due east (west) only on the equinoxes. An observer on the Tropic of Capricorn, at the (southern) summer solstice will see the Sun rise (and set) south of due east (west). Perhaps a Rockhampton resident can confirm this for us? Now, imagine yourself moving further south, beyond Tasmania and towards Antarctica…as you move south the Sun would appear to rise and set even further to the south. Just before you reached the Arctic Circle on the (southern) summer solstice, the Sun would set, and then rise instantly, due south of you. Beyond the Arctic Circle it would remain above the horizon, as we know it does during the summer months.

    • Fletcher, the simple answer is that most of us simply look it up using an app, a PC planetarium program or online – for example at timeanddate. On a more practical and historical level ancient people observed that its rise and set positions repeated in an annual cycle. Placing sticks or stones in the ground marked the rise or set position on important dates, e.g. the midwinter sunrise and set at Stonehenge. But I think you want to know: How do we calculate the positions? Mathematical equations. The ones used are written down in the Astronomical Almanac (the book version not their online site). However, a taste of what’s involved is described here. Typically you first need to calculate the time of sunrise or set at your location (specified by its geographical latitude and longitude) followed by a calculation of the azimuth of the Sun at that time. Over time the calculations have become increasingly sophisticated and complex. I don’t know anyone who has ever calculated a sunrise from scratch! As I noted earlier most scientists simply look up a table or website…and quietly thank someone for putting in a lot of careful hard work.

    • Roy, the simplest answer is: 180-degrees of longitude away from Sydney, i.e. at about 30-degrees west longitude, or in the middle of the Atlantic ocean. However, its a bit more complex than that. At any moment the Sun illuminates half of the globe. The line forming the boundary between night and day is a circle. Half of this circle is experiencing a sunrise, the other half a sunset. As the seasons change the tilt of the Earth causes the circle of sunsets and sunrises to oscillate back and forth over the poles. At the equinoxes this circle intersects both north and south poles. A good visual demonstration of the sunrise and sunset locations shows how this all works.

  • “At the December (summer) solstice it rises south of east, makes a large circle and sets south of east.”

    Surely the last word in that sentence should be “west”!

  • i do realise this, but what im saying – is that over the past 14 years in my current location – this is the furthest South I’ve ever seen the Sun Rise and Set

    this seem to be having a large effect on our weather as to which no one in the scientific community is talking about.

    its like they don’t want to mention this as it goes against their propaganda of the Global Warming garbage.

    winter was a month late in last year and this has all pushed through into summer as well. how cool was January? – this has silenced the disciples of the Climate Change Church this summer thus far.

    there is also a lot of chatter on the net with the people in the Northern Hemisphere about the Earth tilt and sun position.

    • I’m glad you are making observations, they are the basis of all science. However, I haven’t noticed the Sun rising or setting any different to normal. Our telescopes are still working perfectly – tracking the Sun and stars – without any need to adjust for any supposed, but non-existent, change in Earth’s tilt. I see no evidence for unusual behaviour.

  • like the above author, this year 2014/15 summer – I have never seen the Sunrise so far to the South of East and the Sunset, so far South of West – I live in Southern Victoria on the coast at around 38*

    I understand the animation above but I have never seen it like this in my current location over the past 14 years

    its always been Sunrise to the East or North of East – Sunset is West or North or west

    also, Winter was around a month late this year with also a cooler January

    • Andrew, Keep watching as its rise and set positions move northwards over the next few months. You will find it rises and sets almost exactly east and west on the solstice.

  • Hi,

    one question I have not yet found answered is:
    on the summer solstice, how far south of east (in degrees) does the sun rise. am particularly interested for Perth (32Deg south), but would also like to know the formula for calculating for any position on the planet.
    Cheers

  • Hi, I live at 43 degrees north, near Chicago. When visiting southern Chile In January, I was surprised to see the sun overhead to the north, the complete opposite of what I was used to. Sometimes this made finding our way around more challenging if we didn’t keep this in mind. Love your diagram of the sun’s path and website!
    Thanks, Penny

  • Similarly, does this mean that in the northern hemisphere the sun arcs to the south? And if so might this be a reason why I (having been raised in the southern hemisphere) have difficulty with a sense of direction when in the northern hemisphere?

    • Hello John. Yes, in the northern hemisphere the Sun is highest towards the south in the middle of the day. And yes, it is confusing to us southern hemisphere people. Note also that sundials made for the northern hemisphere are useless for the southern.

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