SCIENCE
What color is the sun really?
It may sound like a trivial question, but in fact it is not trivial at all; on the contrary, it holds within it very important physical and philosophical questions. The Washington Post noted that this question is stirring up some of the people on Twitter these days.
The debate was generated by a tweet from journalist Jacqui Deevoy, who wondered how it was possible that the sun had 'changed colour' from what she remembered as a child. The answer, however, is one that leaves one somewhat appalled, as there is no real unequivocal answer.
After all, children do not make a mistake by drawing the sun as a big yellow ball, but it is not a completely right answer. After all, light is just the perception of the wavelength of radiation emitted by the sun, and therein lies the whole secret.
What color is the sun really?
It may sound like a trivial question, but in fact it is not trivial at all; on the contrary, it holds within it very important physical and philosophical questions. The Washington Post noted that this question is stirring up some of the Twitter population these days.
The tweet of discord
The debate was generated by a tweet from journalist Jacqui Deevoy, who wondered how it was possible that the sun had 'changed colour' from what she remembered as a child. The answer, however, is one that leaves one somewhat appalled, as there is no real unequivocal answer.
Do children therefore make mistakes?
No, in the end, children do not get it wrong by drawing the sun as a big yellow ball, but it is not a completely right answer. This is because light is only the perception of the wavelength of radiation emitted by the sun, and therein lies the whole secret.
Even "normal" colors are very subjective
As mentioned, colour perception depends on the wavelength of radiation emitted by the object being observed. However, let us think of a colour-blind person, whose perception of colours is totally different from that of most people. Since we observe through our 'sensory perceptions', 'normal' is still different from person to person, and even more so from animal to animal. So, this is not a trivial question, because it has already raised a philosophical question as well, and we have not yet discussed physics.
Because the sun has not only one color
The way we observe depends precisely on the wavelength of the variations, which in themselves are very different. In fact, they range from infrared to ultraviolet. So, the children who draw the sun as a big yellow ball have a point.
The wavelengths of the sun's radiation.
Indeed, among the long range of radiation, there are some that our eyes (and our brains) perceive as yellow. NASA also explains that radiation is filtered out by atmospheric particles. It should also be known that most of the radiation emitted by the sun is blue-green to our eyes.
Because we see the sun neither blue nor green
The explanation is entirely scientific. Because blue light of shorter wavelength is scattered more efficiently than red light of longer wavelength, we lose some of the sun's blue hue when sunlight passes through the atmosphere.
Why do we see the red sunset?
We see the sunset in a bright orange-red colour since the sun is low on the horizon, and therefore its light must pass through a much thicker layer of atmosphere, which consequently 'removes' an even higher percentage of blue-green radiation, and almost only red radiation manages to reach our eyes.
Why do we see the sun high in the sky white?
After all, what would white be if not the union of all colours together? It is the same for the sun. In fact, what we see as white is actually the result of our mind's integration of all the radiations of the visible spectrum when they reach the photoreceptors in our eyes at the same time.
No one is right, no one is wrong
As we predicted at the beginning, this is the classic answer that satisfies no one, and yet it is so. It cannot be said that the sun is one colour or another. There is no right or wrong answer, but simply there are our perceptions of radiation.
science
27/03/2024
The Six Degrees of Separation Theory, which assumes that each person can be connected to any other in the world through a chain of knowledge with no more than five intermediaries, is one of the most popular and suggestive social theories ever created, and may still be valid today in the age of social networking.
It was in the mid-1960s when a Harvard professor sent a letter to an unknown farmer in Nebraska, hoping that, through a completely random network of contacts, the letter would reach its true recipient in Boston.
Today, a study co-ordinated by the Institute of Complex Systems of the National Research Council in Florence (CNR-Isc) - signed by researchers from Spain, Israel, Russia, Slovenia and Chile - has shown that connections on social networks resemble those found by Milgram in the 1960s.
Art galleries private collections
25/03/2024
In Islam, the ḥajj is the traditional pilgrimage to the Holy Mosque in Mecca; it constitutes the fifth pillar of Islam. The pilgrimage is performed during the Dhū l-Ḥijja which is, in the Islamic calendar, the twelfth month of the year, of 29 or 30 days. In 2023, the pilgrimage is performed in the last days of June (Western calendar).
It is a pilgrimage that every Muslim is obliged to make on a compulsory basis, provided he or she has the means, first of all financial, and then physical. To date, hundreds of thousands of faithful have already celebrated the 'Tawaf of Advent', seven walks around the Kaaba, the black stone cube covered by the kiswa, an Italian silk cloth, embroidered in gold by Saudi artisans.
The significance, for followers of Islam, is to retrace the journey of Ibrahim and Ismail, i.e. Abraham and his son Ishmael in Christian and Jewish traditions.
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Art galleries private collections
Art galleries private collections