I need the inverse of that - an app that predicts how badly a given street will be baked by the sun at current or near-future time, will there be any shadow zone from the buildings, how far will the usable extent of it reach (e.g. not much use of shadow if my head or body stick up beyond the shaded volume). Ideally available on a smartphone. Bonus points for being able to route navigation paths to minimize direct sun exposure.
Motivation: I hate it when it's hot, but my kid has actual issues with heat/sun exposure, and e.g. I had to navigate our way around the city through shaded zones today, just so she doesn't get exhausted in under 30 minutes.
Plenty similar apps are made to sell people photovoltaics, but I'd love to see something to help humans avoid sun.
This is exactly what I am working on for my city (Berlin). Right now it gives you sun/shade times for outside areas of cafes and restaurants as well as heatmaps for public parks and playgrounds.
The idea is to eventually offer a sun or shadow mode and the app will then surface areas, squares, and streets with more sun or shade and eventually offer walking and biking routes with more or less sun.
Smartphones have the huge advantage of direction sensors (3D magnetometer and gyro). I remember using apps like Google sky map (or something like that) way back in 2011 to look at satellites and planets.
It uses the Python lib Astral, which uses "equations from Astronomical Algorithms, by Jean Meeus", to find location of the Sun in the sky. That method assuming earth motion without gravitational pull from other planets or the Moon, and has accuracy of 0.01 arc degree. Meeus is a rock star in these kinds of calculations. He also gave a truncted version of VSOP87 that has error less than 1 arc second in finding Sun's location.
The method Astral uses for calculate Moon's location has precision of 1 arc minute. For higher precision, LEA-406 [1] can be used.
Interesting, I've planned similar shots before and used different tools that serve a similar purpose. The Photographer’s Ephemeris has nice visualizations: https://photoephemeris.com/
NASA's Horizons ephemeris is also pretty good at preparing data for this. I've used it with a little script to check when the sun/moon will be in a given box. This hengefinder looks neat and really streamlined for its purpose though.
Very interesting, but sounds like an extra complication to use binary search on time to find the right position of the sun, when you can just directly calculate this, eg. using the formulas in here: https://gml.noaa.gov/grad/solcalc/solareqns.PDF
I lived a long time in a city near the equator with a prominent east-west street. Commuting west to east in the morning and east to west in the evening meant frequent hengings. The roads don't feel particularly safe when you can't see anything. The town planners might have considered this.
Living in the US Midwest, there are lots of towns that are laid out on north-south grids, including portions of mine. As a cyclist, I take note of the days when the sun is coming up over east-west streets, because the car drivers can barely see where they're going. I once saw a multi-car crash on my own street (fortunately at very low speed) that I attributed to this effect.
Any angle within 23º of east-west will have henging at some time of year. You'd have to have the entire street grid be aligned diagonal rather than cardinal.
Additionally I have visited Stonehenge and it's sterilised and disappointing being unable to walk amongst the stones. Thank you for your attention to this matter.
On a similar note, for this August's total solar eclipse (in Europe), I 3D modelled the sun's position in the sky from the viewpoint that I am planning to go to. The eclipse will happen late in the day when the sun will be low, so I wanted to make sure that nothing will obstruct my view!
I’d like to subscribe to stick™ pro! I tried a piece of string and it waved around in the wind and didn’t work, so I think I may need a paid service for this.
Nice, and awesome that it works internationally. One little feature request: provide an .ics download, so that I can add a calendar event, add a link to the original calculation to the the calendar entry.
Yep, if I use street name it attaches to wrong part of the street, if I use a place next to the street it attaches to the place, not the street. Couldn't figure out how to drag the origin point of the arrow
I need the inverse of that - an app that predicts how badly a given street will be baked by the sun at current or near-future time, will there be any shadow zone from the buildings, how far will the usable extent of it reach (e.g. not much use of shadow if my head or body stick up beyond the shaded volume). Ideally available on a smartphone. Bonus points for being able to route navigation paths to minimize direct sun exposure.
Motivation: I hate it when it's hot, but my kid has actual issues with heat/sun exposure, and e.g. I had to navigate our way around the city through shaded zones today, just so she doesn't get exhausted in under 30 minutes.
Plenty similar apps are made to sell people photovoltaics, but I'd love to see something to help humans avoid sun.
There’s a few sites that do what I think you’re asking for, not navigation though. This is one I’ve used recently: https://shademap.app/
This is exactly what I am working on for my city (Berlin). Right now it gives you sun/shade times for outside areas of cafes and restaurants as well as heatmaps for public parks and playgrounds.
The idea is to eventually offer a sun or shadow mode and the app will then surface areas, squares, and streets with more sun or shade and eventually offer walking and biking routes with more or less sun.
This could also be a legitimate lifesaver in places like India where extreme heat is common but delivery and gig workers have to travel outdoors.
It would be nice to be able to access the website on a smartphone (even if the experience is suboptimal), instead of denying access.
Smartphones have the huge advantage of direction sensors (3D magnetometer and gyro). I remember using apps like Google sky map (or something like that) way back in 2011 to look at satellites and planets.
Not sure if this is the app you were referring to, But Stellarium does exactly what you're describing.
There's a mobile app that supposedly works worldwide (but isn't available in my country).
Really wish mobile browsers were better liars when it comes to "desktop mode"
Seriously. Plus, what is the problem that some websites are 'fixing' by denying me a choice in how the website loads?
[dead]
It uses the Python lib Astral, which uses "equations from Astronomical Algorithms, by Jean Meeus", to find location of the Sun in the sky. That method assuming earth motion without gravitational pull from other planets or the Moon, and has accuracy of 0.01 arc degree. Meeus is a rock star in these kinds of calculations. He also gave a truncted version of VSOP87 that has error less than 1 arc second in finding Sun's location.
The method Astral uses for calculate Moon's location has precision of 1 arc minute. For higher precision, LEA-406 [1] can be used.
[1] https://www.aanda.org/articles/aa/full/2007/33/aa7568-07/aa7...
Interesting, I've planned similar shots before and used different tools that serve a similar purpose. The Photographer’s Ephemeris has nice visualizations: https://photoephemeris.com/
NASA's Horizons ephemeris is also pretty good at preparing data for this. I've used it with a little script to check when the sun/moon will be in a given box. This hengefinder looks neat and really streamlined for its purpose though.
Very interesting, but sounds like an extra complication to use binary search on time to find the right position of the sun, when you can just directly calculate this, eg. using the formulas in here: https://gml.noaa.gov/grad/solcalc/solareqns.PDF
Various apps for (primarily) photographers offer views of the sun's (and moon's) path, even with live view through the camera.
For example https://www.sunsurveyor.com/ or https://www.photopills.com/ best among others
I lived a long time in a city near the equator with a prominent east-west street. Commuting west to east in the morning and east to west in the evening meant frequent hengings. The roads don't feel particularly safe when you can't see anything. The town planners might have considered this.
Living in the US Midwest, there are lots of towns that are laid out on north-south grids, including portions of mine. As a cyclist, I take note of the days when the sun is coming up over east-west streets, because the car drivers can barely see where they're going. I once saw a multi-car crash on my own street (fortunately at very low speed) that I attributed to this effect.
Any angle within 23º of east-west will have henging at some time of year. You'd have to have the entire street grid be aligned diagonal rather than cardinal.
Additionally I have visited Stonehenge and it's sterilised and disappointing being unable to walk amongst the stones. Thank you for your attention to this matter.
On a similar note, for this August's total solar eclipse (in Europe), I 3D modelled the sun's position in the sky from the viewpoint that I am planning to go to. The eclipse will happen late in the day when the sun will be low, so I wanted to make sure that nothing will obstruct my view!
I've been meaning to post about it.
Stonehenge of course, famously not a henge.
Apparently the word "henge" comes from the name Stonehenge but Stonehenge has the ditch on the wrong side of the bank to technically be a henge.
For any other curious people: https://www.english-heritage.org.uk/visit/inspire-me/what-is...
Ye - also the henge is the circular ditch, not the stone circle or whatever in the centre
Mobile app not available in your country. :(
then use a stick™
hint, watch the sticks shadow
other hint, can use almost anything that casts a shadow, as a stick substitute.
* even more hints availible with stick™ pro
I’d like to subscribe to stick™ pro! I tried a piece of string and it waved around in the wind and didn’t work, so I think I may need a paid service for this.
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Nice, and awesome that it works internationally. One little feature request: provide an .ics download, so that I can add a calendar event, add a link to the original calculation to the the calendar entry.
older, better alternative: https://suncalc.net/
Manhattanhenge is cool but people standing in the middle of street for it is pretty nuts.
it’s nuts that more streets in manhattan aren’t pedestrianized
this is true
It doesn't work with curved streets.
Any sufficiently small section of the street is indistinguishable from a straight street.
Tell that to all the buildings blocking the light
Yep, if I use street name it attaches to wrong part of the street, if I use a place next to the street it attaches to the place, not the street. Couldn't figure out how to drag the origin point of the arrow
The sun?
It would be good to also have the option for alignment with sunrises in addition to sunsets.
For instance in Houston the sunrise aligns with Texas Avenue around the June solstice.
Consequently, there are no sunset alignments for the downtown skyscrapers.