Itâs Not the Needle That Hurts. I believe the pain is due to the solution used to clean the eye prior to the injection and not the needle itself. The solution is called âBetadineâ and is commonly used to cleanse the eye prior to intraocular injection. Most retina specialists use this a part of their routine.
For numerical convenience, an object brighter than 0th magnitude has a negative magnitude; the brightest star, Sirius is magnitude -1.4; the full moon is magnitude -13, and the Sun is a blazing -26th magnitude.
If we have two stars of the same luminosity with one star double the distance of the other from the Earth the closer star will look four times brighter. It obeys the inverse square law. The photograph shows the Pleiades star cluster. The brighter stars look about the same brightness in fact they are.a) for a star with a certain surface temperature the bigger the star the more energy it gives out. A star with double the radius of another one will have an area four times as great and so have a luminosity four times greater than the first star.