Questions tagged [sun]

Questions in regards to outdoor sunlight or solar related questions.

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12 votes
8 answers
4k views

How can I cover the upper part of my nose to avoid UV radiations?

I use hat + hood + sunglasses + neck gaiter + UV umbrella to fully covered my face when going outside if too much sun. The problem is the upper part of my nose is not fully covered, e.g.: Larger pics:...
Franck Dernoncourt's user avatar
4 votes
1 answer
444 views

What is the difference between SPF and UPF, if any?

I read on https://en.wikipedia.org/w/index.php?title=Sun_protective_clothing&oldid=930941768: A relatively new rating designation for sun protective textiles and clothing is UPF (Ultraviolet ...
Franck Dernoncourt's user avatar
4 votes
2 answers
1k views

Would Mud Prevent Sunburn? [duplicate]

If you had no sunburn cream, would it work to cover your exposed skin in mud and gunk as a crude way to prevent sunburn? I have never tried it. I have tried using paper tissues on my face as a sun ...
Snack_Food_Termite's user avatar
2 votes
2 answers
121 views

How to tell whether a particular pair of sunglasses will effectively protect your eyes?

This detailed paper https://www.aoa.org/Documents/CRG/Blue%20Light%20and%20Eye%20Damage.pdf from the American Optometric Association details the various types of short term (i.e. snow blindness) and ...
mmcc's user avatar
  • 3,466
6 votes
2 answers
99 views

What to look for in eco-friendly sunblock?

With sunblock it's relatively easy to know what to look for in terms of SPF, UV types etc, however with eco-friendly ones that aim to not put chemicals back in the ocean (used by surfers, swimmers, ...
Aravona's user avatar
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5 votes
1 answer
1k views

How to detect significant sun damage in a plastic molded kayak?

Molded kayaks are usually made of polyethylene, an otherwise extremely durable material which can be damaged by the sun. The used market is full of kayaks manufactured ten or twenty years ago which ...
mmcc's user avatar
  • 3,466
6 votes
2 answers
1k views

Has extended exposure to sunlight and UV in the arctic or antarctic ever caused someone's eyes to change color?

In Biology SE I have just asked Could being exposed to excess UV in the arctic lead to a human eye color change? If so, what is the mechanism? but comments there questioned weather Arctic hiker Robert ...
uhoh's user avatar
  • 981
7 votes
3 answers
262 views

Is parasol a good gadget to stay cool walking around the city and parks?

I've only seen parasols being used in movies, cartoons and other artistic media, but extremely rarely in real life. Somehow it feels like I would look ridiculous with one in hand walking around the ...
user1306322's user avatar
6 votes
2 answers
162 views

Approximating the time remaining before sun is set and it starts getting dark

Is there a definite way of approximating the time remaining before sun is set and it starts getting dark? I do understand that there is a time difference between 'Sunset' and the 'moment when it gets ...
WedaPashi's user avatar
  • 31.7k
2 votes
1 answer
129 views

How to estimate the time between direct sunlight and sunrise?

Sometimes due to a high ridge or other land feature, the time that the sun comes over the horizon and gives direct sunlight is different from the time calculated by a sunrise table. From personal ...
Charlie Brumbaugh's user avatar
1 vote
1 answer
1k views

Can I use sunlight to purify water without a special container?

According to the answers at Does water in the sun get purified from or polluted by algae, fungi and bacteria? & Can sunlight be used to purify water? water in special containers can be purified in ...
James Jenkins's user avatar
5 votes
1 answer
123 views

Where in nature can we find examples of natural "hoods" - either for reducing UV / sun exposure or for providing shelter from rain?

I'm in the process of designing a more functional "hood" to block UV / sun exposure and also provide shelter from rain. I believe that the best gear and products are developed by "looking to nature" ...
Ryan Chase's user avatar
4 votes
5 answers
5k views

Do some parts of the world really have 12 hours of daylight each day of the entire year?

I live about 45 degree north latitude. Other then at the Equinox, daylight is seldom 12 hours. Sometimes it is more sometimes less. The summer sun can last 16+ hours. I understand how and why there ...
James Jenkins's user avatar
1 vote
1 answer
160 views

What situations/locations would be ideal for using a solar stove while backpacking?

After answering this question, I am wondering when it would be useful to cook with a solar stove. It certainly wouldn't make sense in an area that is constantly overcast or when speed is of the ...
Charlie Brumbaugh's user avatar
5 votes
1 answer
178 views

Are there any techniques to cooking food when camping in the wild by harnessing the energy of the sun?

Are there any techniques to cooking food camping in the wild by harnessing the sun's energy (rays)? We have all heard of solar panels being used to generate electricity, but are there any techniques ...
Ken Graham's user avatar
  • 9,609
13 votes
5 answers
3k views

Do I need a hard shell to ski in sunny weather conditions?

I'm going skiing for the first time. From what I've read, most everyone uses hard shell jackets and pants for skiing. However, they usually mention something about skiing in bad weather, frigid cold ...
Chris Mendez's user avatar
  • 7,210
9 votes
1 answer
2k views

Does water in the sun get purified from or polluted by algae, fungi and bacteria?

We live at 27° latitude, about 200 metres above sea level and drink water from PET bottles laying around on the soil (SODIS method). They are filled with fresh water from a well and reused over and ...
erik's user avatar
  • 201