# Tag Info

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What is the intensity distribution of visible light over the solar disk? What is the distribution of the visible spectrum over the solar disk Hopefully I've answered all the different questions. The core of the sun is extremely hot (27 million degrees Fahrenheit) compared to the surface (10,000 degrees Fahrenheit) and the atmosphere (36,000 to 2 million ...

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If you have the right filters and equipment you can make doppler measurements of the $H_\alpha$ line from the sun. Since an H-alpha telescope directly detects this you can use this to measure the doppler shift. Using this you can measure the rotation rate of the sun. This has been done before with a different telescope and the paper is here. It should also ...

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Yes, all of those contribute to the total irradiance, which is the amount of sun power falling on a particular area, measured in Watts per square meter. You can imagine a 1m$^2$ "window" perpendicular to the sun's rays - excluding atmospheric and weather effects, the amount of sunlight passing through that window never changes. But when the sun is directly ...

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IAU SOFA and SPICE are overkill for what you need, and would require writing a C to C# wrapper around them. An implementation of VSOP87 in C# is all you really need. This is what was used to create NASA's Five Millennium Catalog of Solar Eclipses. The linked code has functions for getEarth() and getMoon() which return the heliocentric XYZ coordinates, the ...

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This idea would be a direct reduction from Newton's laws of motion. In his Principia he states "Hence the common centre of gravity of the earth, the sun, and all the planets, is to be esteemed the centre of the world". So that would be the first evidence of the Sun moving outside of a geocentric universe. Of course he wouldn't have known about Uranus and ...

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Remember that a magnetic field is just that: a field . There's no mass there. Its shape depends on the electromagnetic properties of Earth -- primarily the behavior of the outer core. When there's a significant Solar ejection, the electrically active particles in that mass cause local changes in the magnetic field pattern (equivalent to isobars , or ...

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Yes. After the charged particles that have distorted the magnetic field passed, it goes back to normal. Otherwise it could not have been doing this for the last few billion years. This then looks something like this (data from the ACE satellite): And look here for awesome real-time data. (Thanks Magic Octopus Urn for the comment!) Or see this video for a ...

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$\nabla B^2 \sim B^2/l,$ where $l$ is a length scale on which $B^2$ varies. In SI units, $B^2 \sim 4\times 10^{-8}$ T$^2$ and $\mu_0 = 4\pi \times 10^{-7}$, so an order of magnitude for $\nabla \cdot P_B$ is $4\times 10^{-8}/(8\pi \times 10^{-7}\times 10^{6}) \sim 10^{-8}$ Pa/m. The density of the solar photosphere (at optical depth unity in the visible ...

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Not really an answer to that specific question, but I think its neat that we could actually measure this reflection on exoplanets. There is a neat astrobite about a recent paper discussing ocean glint on exoplanets. They calculate how this reflection changes the overall spectrum of an exoplanet (with Earth as an example): However, we probably have to ...

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Sure it does, and it's beautiful! Here's a GIF from the YouTube video Earth from Himawari-8 satellite which I found in but any geosynchronous Earth observation satellite imagery will show this, such as the video Planet Earth in 4K found in this now-deleted answer. See also: this answer to Could a binary system of two planets with oceans reflect each other?...

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