FSB Sun Facts

By: FSB Team

In every issue of the FSB, we like to publish a series of scientific fun facts so readers can learn a little bit about a wide array of topics. For our summer issue, we decided to publish a series of Sun facts as well as fun facts!

1. How hot is the sun?

The hottest part of the Sun is its core, where temperatures top 27 million °F (15 million °C). The photosphere, the surface of the sun, is cooler, only 10,000 °F (5,500 °C). The Sun’s outer atmosphere, the corona, gets hotter the farther it stretches from the surface and reaches up to 3.5 million °F (2 million °C). While the sun is the largest object in our solar system with a diameter of 865,000 miles (1.4 million kilometers), it’s only an average star in terms of size. Other stars are larger (stars up to 100 times larger have been found) and hotter.

2. What causes a sunburn?

When skin is subjected to too much ultraviolet (UV) light, the skin cells are damaged. If the damage is beyond repair, the cells die and blood vessels dilate to increase blood flow and bring immune cells to the damaged skin. This causes the redness, swelling and inflammation known as sunburn. Sunburn can be caused by UV radiation from the sun or artificial sources, such as tanning beds.

Sunburns are categorized according to how deep the damage is in the layers of the skin. A first-degree sunburn is one in which there is damage to the skin’s outer layer (epidermis). It will usually heal by itself in about a week. A second-degree sunburn is one in which the middle section of the skin (dermis) has been damaged. Blisters will develop and it may take weeks to heal. A third-degree sunburn is very rare. It severely damages all layers of the skin, including the fat layer beneath the skin. Most third-degree burns result from fires or chemical burns rather than sun exposure.

The Sun: Fascinating facts about our incredible star – Collins — Source: Collins

3. How does sunscreen protect the skin?

There are two types of sunscreen: organic sunscreens, also known as chemical sunscreens, and inorganic sunscreens, also known as physical sunscreens. Organic sunscreens are absorbed by the skin and protect the skin by absorbing UV radiation and transforming the energy into heat, which disperses from the skin. They typically include oxybenzone, avobenzone or octinoxate. These sunscreens are often designed to protect against both UVA and UVB radiation. Inorganic sunscreen sits on top of the skin’s surface and acts as a physical barrier that reflects and scatters UV radiation. They contain mineral compounds such as zinc oxide and titanium oxide. A broad-spectrum sunscreen contains compounds that absorb and/or reflect both Ultraviolet A (UVA rays) and Ultraviolet B (UVB) rays. UVB is the principal cause of sunburn, but both UVA and UVB increase the risk of skin cancer. Many sunscreens combine organic and inorganic compounds to provide broad-spectrum protection.

4. How do sunglasses protect the eyes?

Sunglasses protect the eyes against harmful ultraviolet rays that can damage the cornea and retina. They also protect the eyes from intense light, which causes squinting and can damage the retina. Polarized sunglass lenses eliminate glare, and depending upon the type of lenses used, sunglasses can also block or enhance frequencies of light that blur vision or stimulate the body to go to sleep or stay awake.

5. What is Manhattanhenge and why does it happen?

Mahnattanhenge occurs when the alignment of the sun with Manhattan’s street grid creates a radiant glow that simultaneously illuminates the north and south sides of every cross street. The sun only rises/sets due east/due west twice a year, on the Spring Equinox and the Autumn Equinox. Every other day, it rises and sets at other points on the horizon.

Manhattanhenge occurs on days when the sunrise or sunset aligns with Manhattan’s street grid, which is rotated 29 degrees from true east-west. The sunset alignment occurs around May 28th and July 13th, and the sunrise alignments occur around December 5th and January 8th.

In addition to the rectilinear street grid, other unique features of Manhattan make Manhattanhenge possible – the clear view to the horizon across the Hudson River and the tall buildings that line the streets and frame the setting sun.

Sources:

https://science.nasa.gov/sun/facts

https://www.mdanderson.org/cancerwise/what-happens-when-you-get-a-sunburn.h00-159699123.html#:~:text=%E2%80%9CSunburns%20are%20from%20ultraviolet%20radiation,these%20mutations%2C%E2%80%9D%20George%20says

https://my.clevelandclinic.org/health/diseases/21858-sunburn

https://www.livescience.com/health/how-does-sunscreen-work

https://www.mdanderson.org/cancerwise/sunscreen-myths-debunked.h00-159697545.html#:~:text=Myth%201:%20All%20sunscreens%20work,of%20UVB%20rays%20it%20blocks.

https://www.amnh.org/research/hayden-planetarium/manhattanhenge

Featured Image Source: Freepix