Cataclysms such as novas, kilonovas, supernova, magnetars, quasars, gamma ray bursts are rarely visible from Earth. Under what conditions (such as distance, day vs. night, naked eye vs. level of…
A comment under this answer states that the apparent angular speed of the Sun is 8% slower during the solstices. This is rather counter-intuitive, since the rotation speed of the Earth is constant…
My current/previous telescope is a Skywatcher 60/900 refractor on an equatorial mount. I am now looking at a SkyWatcher 150/1200 "Classic" Dobsonian reflector. How can I compare the two in
The Saha Equation: $$frac{N_{i+1}}{N_{i}} = frac{g_{i+1}}{g_{i}}frac{g_e}{N_e h^3}(2 pi m_{e} kT)^{3/2} exp(- chi_i / kT)$$ where $chi_i$ is ionization potential. My problem is about the s…
I know about in-the-sky.org and its online planetarium feature, but that's from the Earth's perspective. Is there a planetarium (preferably online but if not, that's fine) where the observer is on