5/26/2023 0 Comments Alive in the end of the sun![]() This second response is also called melanogenesis and happens when our skin is exposed to UVA radiation. The second and slower response of our skin cells to sunlight is called "delayed tanning". You can't easily see this happen with lighter skinned people but it is more obvious with people with darker skin. ![]() This is a quick response that happens over a period of minutes to days. This happens when our cells are exposed to UVB or ultraviolet type B radiation. First our cells experience the "immediate pigment darkening" response when exposed to the sun. This is one reason why our body darkens the skin when exposed to sun- to protect us.īleached hair: a tell tale sign of too much sun and surfing. The UV light from the sun can damage DNA and cause cancer. Why do we even need this coloring? Melanin helps protect our skin and hair by filtering out potentially harmful ultraviolet (UV) radiation from the sun. How much of each kind of melanin we make determines the exact shade of our skin and hair color. Eumelanin has a brown or black color while pheomelanin is yellowish-red. Special cells in the skin, called melanocytes, make two different types of melanin, eumelanin and pheomelanin. That's the simple answer, now let's get into the details. Your skin cells make more melanin and your skin becomes darker. But since your skin is alive, it can respond to the sun's damage. When sun shines on your skin, it destroys the melanin as well. Since hair is dead, the hair will stay that color until new hair comes in. ![]() The sun bleaches and destroys the melanin in your hair giving you lighter hair. This mostly has to do with hair being dead and skin being alive. It does seem weird that the sun bleaches our hair and darkens our skin. Melanin is a pigment found in your skin and hair cells that gives each its color. It will transform into a red giant star at around 10 billion to 11 billion years of age.That is a great question and worth investigating! You are right in thinking that melanin has something to do with the answer. This resulted in 5,863 Sun-like stars across the entire Hertzsprung-Russell diagram, from very young to very old.īy identifying only the most Sun-like stars, Creevey and her colleagues were able to confirm the timing of its demise.īroadly consistent with previous projections of the Sun's lifespan, its temperature will peak at around 8 billion years of age. That's because low temperature stars tend to be smaller, and live longer than the hotter ones looking at cooler stars, therefore, can potentially reveal more about the history and stellar evolution of the Milky Way and the wider Universe.īecause this temperature range includes stars like the Sun, the data could be used to zero in on stars with a similar mass and chemical composition as the Sun. Eventually, it will run out of hydrogen and helium, eject all its outer material to form a planetary nebula, and the core will collapse down into a white dwarf, which could take trillions of years to cool completely.Ĭreevey and her team initially started combing the Gaia data because they wanted precision observations of stars with relatively 'cooler' temperatures between 3,000 and 10,000 Kelvin. This hydrogen then starts to fuse, dumping helium into the core, in a process called shell burning.ĭuring this, the outer atmosphere of the Sun will expand by a lot, maybe even as far as the orbit of Mars, turning it into a red giant. The core will start to contract, a process that brings more hydrogen into the region immediately around the core, forming a hydrogen shell. It will continue to grow hotter over the next few billion years, eventually running out of hydrogen to fuse in its core. We already know in some detail what will happen in our Sun's future. "If we don't understand our own Sun – and there are many things we don't know about it – how can we expect to understand all of the other stars that make up our wonderful galaxy," said astronomer Orlagh Creevey of the Observatory de la Côte d'Azur in France.
0 Comments
Leave a Reply. |