I am attempting this past paper question and am not sure how to tackle this, this is not homework! :) The spectrum of a distant quasar shows two broad emission lines with observed wavelengths…
È un presupposto che la velocità di propagazione delle onde gravitazionali sia esattamente la stessa della velocità della luce? Se la velocità di gravità è solo leggermente inferiore alla velocità della luce, l'effetto...
A moon-sized object is running loose in the Solar System, perhaps after a planetary collision. As it approaches a planet, it's presumably following an approximately hyperbolic path. If it goes on…
As beginner, I would like to understand how planets exhibit retrograde motion. When does the retrograde motion start for a planet like Mars and how long (time limit) planets will appear to be in such
This great answer by @gerrit discussing planetary phases seen in visible light contains the image I've included below. According to the Wikimedia Commons link these are ESO images from the Venus tr…
Most diagrams I see of sunlight look like something like this: . They show that for basic geometric analyses, the sun's radiation can be thought of as 'thin lines' that strike earth. Further, at an