Make arrangements to view a comet through a telescope. Because astronomers discover roughly a dozen comets each year, a comet is usually visible somewhere in the sky. Unfortunately, because most...

Make arrangements to view a comet through a telescope. Because astronomers discover roughly a dozen comets each year, a comet is usually visible somewhere in the sky. Unfortunately, because most comets are quite dim, you will need access to a moderately large telescope. You can use Starry Night Enthusiast™ to see which comets are visible. First, update comets on-line by opening the LiveSky menu at the top of the program and clicking on Update Comets/Asteroids/Satellites. Close and restart the program. Set the time in the toolbar to your expected observing time, Stop Time flow, and then find a comet that is visible by opening the Find pane, clearing the search box and expanding the Comets list. The names of those comets visible at your selected observing time will be in black font. Find its apparent magnitude by clicking the menu button at the extreme left of the listing for the comet and select Show Info. Find the comet’s apparent magnitude under the Other Data layer of the Info pane. A comet fainter than about 12th magnitude will not be easily visible. If the brightness of the comet you have chosen is too low, try other comets. Remember that the larger the apparent magnitude value, the lower the brightness. Double-click on one and zoom in on it to see the direction of its tail. You can print finder charts as described in the previous Observing Project on asteroids. Alternatively, consult the Web or recent issues of the IAU Circular, published by the International Astronomical Union’s Central Bureau for Astronomical Telegrams, which contains predicted positions and the anticipated brightness of comets in the sky. Also, if there is an especially bright comet in the sky, the latest issue of Sky & Telescope might contain useful information. Observe the comet through a telescope. Can you distinguish it from background stars? Can you see its coma? How many tails do you see? (Note that a telescope with a low magnification or a pair of binoculars is more suitable for viewing a bright, nearby comet with an extended tail, because this comet is a diffuse source of light.)