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6

That was a rather recent (16 January 2021) change to that wiki page made by a user named Mariofeds, who does not have a wikipedia user page and who has just one contribution to wikipedia. It may well have been vandalism. The associated talk page explicitly excludes adding the hypothetical Planet Nine as an unconfirmed planet. In line with this discussion, ...


3

If I understand your question correctly, it is about EPI-Lo which a part of the Integrated Science Investigation of the Sun (ISʘIS) . The picture is also taken from there: EPI-Lo stands for Energetic Particle Instrument-Low energy which indeed sounds confusing at first sight. The essential definition can be found in the instrument paper: EPI-Lo measures ...


25

There are three main reasons why we can tell that local stars did not, for the most part, form from the same molecular cloud that the Sun formed from. The first is that unless stars are born in a very tightly bound system such as a globular cluster (which the Sun is definitely not in), they will drift apart from their birth companions over time in slightly ...


19

Is it possible that the Sun and all the nearby stars formed from the same nebula? No, it is not. Our Sun has marked differences in metals compared to the nearby stars. (In astronomy, every element higher than helium is a "metal".) The discovered and analyzed stars that appear to be most similar to the Sun are far, far away from the Sun. Our Sun ...


5

Nuclear reactions can have particular energy spectra, which arise based on how energy and momentum are distributed among the product particles. This holds true for neutrinos produced in the many different stages of the CNO cycle, as well as the pp chain. The authors began the paper with a figure showing the theoretical neutrino fluxes for the various ...


-1

Basically, the sunlight is reflected from the Moon at different angles. It works the same as on Earth. For instance, during the sunrise & sunset, the sunlight is reflected at a bit above 0 degrees angle, whereas at the noon in the tropical areas (in general) where Sun passes the zenith, the sunlight is reflected at 90 degrees. On Moon and other planets, ...


4

Solar energy - from our Sun at Jupiter's focal distance? A negligible amount. Gravitational lensing doesn't have a focal point so much as a focal region that begins roughly at a point, and that point (which really shouldn't be called a focal point) can be calculated, ProfRob gives the formula here. Jupiter's gravitational lensing distance is so far (...


2

The thermal energy of the Sun is something like $$E \sim \left(\frac{3k_BT}{2}\right)(N_i + N_e)\ , $$ where $N_i$ is the number of ions and $N_e$ is the number of electrons and the interior temperature $T \sim 10^7$ K. To first order we can consider the Sun to be made of hydrogen, so $N_e = N_i \sim M/m_p$, where $m_p$ is the mass of a proton. Putting in ...


5

I found an article by Ian O'Neill posted on May 2, 2008 at universetoday.com with the title Could Jupiter Wreck the Solar System? which says But here’s the kicker: There is only a 1% chance that these gravitational instabilities of the inner Solar System are likely to cause any kind of chaos before the Sun turns into a Red Giant and swallows Mercury, Venus, ...


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