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.
The Visual Magnitude Scale. Visual brightness of stars, planets and other astronomical objects is based on the visual magnitude scale (Vo). Every integer increase in magnitude represents a 2.5 increase in brightness. So the Sun is 6 trillion times brighter than a 6th magnitude star, which in turn is 4 billion times brighter than a 30th magnitude star-the limit of the Hubble Space Telescope. 1  Magnitude (Vo). 2  Object or Limit. - 3 27.