Set your target and optics, then head to the chart.
Many star charts come close to what a visual deep-sky observer needs, but they stop at about magnitude 17, or bury the field under deep-sky objects you have no chance of seeing. That clutter makes it hard to match the chart to the eyepiece and find a faint fuzzy. Star Hop draws stars only, all the way down to magnitude 20, so the pattern you see in the eyepiece is the pattern on the chart. When you want to see exactly where your target sits among those stars, add a sky-survey photograph as an overlay on the chart page.
Objects are looked up live in the SIMBAD astronomical database instead of a built-in list, so the catalog is always current. The price is time: a lookup can take up to 30 seconds, so please be patient while the spinner turns.
Search by name or number, such as M 51 or UGC 2838. Choose a type to narrow a bare number like “2838”. Or skip the search and enter the J2000 position below.
Describe your equipment once and Star Hop remembers it: your telescopes, eyepieces, Barlows and, if you use one, a night-vision image enhancer. They are saved in a cookie in this browser for one year, and the year restarts each time you open a chart, so after your first visit all you need to tell Star Hop is what you’re looking for. Each computer, phone and browser keeps its own copy, so enter your gear once on each. (Safari may expire it sooner, after about a week.) You choose which telescope and eyepiece to use on the chart page.
Newt = Newtonian reflector; SCT = Schmidt Cassegrain reflector with a diagonal. This selection configures the chart page to show the stars as they appear in the eyepiece.
Name, focal length in millimetres, and apparent field of view in degrees (from the maker's specifications).
Enter the magnification factor, such as 2 for a 2× Barlow, or 0.63 for a focal reducer. You switch them on and off on the chart page.
Email the link to yourself and open it on your other computer or phone. Your settings are inside the link itself, after the #, so they never reach our server.