How Hot Is the Sun?

The Sun is composed of hydrogen, which makes up 74% of its mass and 92% of its volume, and helium, which makes up 24-25% of its mass and 7% of its volume, along with other elements such as Fe, Ni, O, Si, S, Mg, C, Ne, Ca and Cr.

In short, the Sun's energy comes from the fusion of hydrogen into helium in its core, where the pressure is billions of times greater than Earth's atmospheric pressure.

The largest celestial body in the Solar System is the SUN!

Explosions equal in power to millions of atomic bombs occur on the Sun's surface every second. To describe the size of these explosions, they take the form of flames that are 40-50 times the size of the Earth.

The temperature on the Sun's outer surface is 6,000 degrees, while the temperature at its core is 12 million degrees!

Appearing like a ball of fire, the Sun emits large amounts of heat and light from its surface.

From a distance of approximately 150 million kilometers, the Sun makes life on Earth possible. If we were to board a space shuttle traveling at 1,000 kilometers per hour, we would not reach that distance even in 17 years.

To put into perspective the average 25-40 degree temperatures we feel on Earth, the temperature on the Sun's outer surface is 6,000 degrees, and the temperature inside it is around 12 million degrees.

So what about the harmful UV rays from the Sun that reach our planet?

UV FILTERS

Ultraviolet (UV) light refers to sunlight at different wavelengths that cannot be seen with the naked eye. UVA and UVB rays reach our skin every day, passing through the ozone layer. The ozone layer can only block UVC rays. The UVA, UVB and UVC wavelengths can be understood more clearly in the chart below.

UVA is responsible for skin tanning and aging. It has wavelengths between 315 nm and 400 nm.

UVB damages DNA and causes tissue damage and sunburn. UVB rays have wavelengths between 280 nm and 315 nm.

UVB is biologically more active than UVA.

UVC is the most toxic wavelength band, but most of it is absorbed by the atmosphere.

UVC is germicidal.

To minimize the harm from these harmful rays, we need to use various cosmetic preparations. To make these preparations protective against UV rays, various UV filter agents are used. The commonly used ones are as follows: Avobenzone, Benzophenone-3, Benzophenone-4, Octocrylene, Homosalate, Octinoxate, Ensulizole, Titanium dioxide, Zinc oxide, etc.

AVOBENZONE

Butyl Methoxydibenzoylmethane

• An oil-soluble UVA and UVB filter.
• Used in sun care products, hair care products, protective creams, lotions and makeup materials.

BENZOPHENONE-3

Oxybenzone

• An oil-soluble UVA and UVB filter.
• An antioxidant.
• Used in personal care products such as sunscreens, lip balms and nail polish to protect against UV light.

BENZOPHENONE-4

Sulisobenzone

• A water-soluble UVA and UVB filter.
• An antioxidant.
• For effective UVB protection, it should be combined with other sun filters (e.g., octocrylene, homosalate, ethylhexyl salicylate, OM-cinnamate). When Benzophenone-4 is used alone, it provides insufficient UVB protection.
• Helps with stabilization in UV-sensitive formulations such as hair dyes and hair sprays.

OCTOCRYLENE

• An oil-soluble, stable UVB filter.
• A chemical compound generally used as an additive. It is preferred in creams for the skin due to its sun filter, moisturizing and softening effects.

HOMOSALATE

Homomenthyl salicylate

• A UVB filter in oily liquid form.
• Homosalate is an organic compound, a derivative of the ester of salicylic acid and 3,3,5-trimethylcyclohexanol (cyclohexanol derivative).
• One of the core sunscreen agents for UVB protection.
• Can be combined with other sun filters.

OCTINOXATE

Ethylhexyl Methoxycinnamate

• A UVB filter in oily liquid form.
• Can be used with BHT for stability.
• Can be used in sun care and after-sun products, hair care products, protective creams and lotions, and makeup products.

ENSULIZOLE

Phenylbenzimidazole Sulfonic Acid

• A water-soluble UVB filter.
• Sunscreen agent.