Nov 2017

A DEC 3 Lunar and Two December Solar ISS transits

by John Hlynialuk

The website I use to determine the best viewing locations for ISS transits is It allows you to designate your home latitude and longitude and select a travel radius and range of dates (about a month ahead). I picked 140 km as a travel radius, and it give me the transits that are within a couple of hours driving distance from Owen Sound, ON. There is one lunar transit of the superMoon on Dec 3 and two solar transits in December as well, Dec 8 and Dec 12. Some details for those are provided below.

Dec 3:
lunar transit occurs across the Full Moon but the ISS is not illuminated this time so you have to be watching at the right time (10:11 pm EST ) for the passage of the ISS silhouette, Centreline of the transit is from just S. of Sauble Beach over Allenford and thence SE towards Keady, Markdale, Flesherton and eventually Toronto. (See second map below). This is a short transit of about 1 second silhouetted against the bright super full Moon) with the moon 48° above the western horizon. Time is Dec 3 at 10:11 pm EST. Check for the path in your area if you are outside of Bruce-Grey.

Screen Shot 2017-11-30 at 2.59.38 PM

Screen Shot 2017-11-30 at 2.54.41 PM

Dec 8:
solar transit occurs in mid-afternoon at 2:33 pm EST and lasts about 3 seconds as well but the outline of ISS should be visible for the entire time. The Sun is just about in the same position in the sky as the lunar transit two weeks earlier. This time make sure you use solar filters on your telescope. This is the Sun you are looking at! Area of visibility is about the same coincidentally as the lunar transit of Nov 24, but centred over Hope Bay and Cape Croker. Howdenvale is well-placed.

Dec 8 solar

Dec 12:
solar transit occurs with a track of visibility farther south this time and visible Port Elgin to Big Bay. The Sun is a bit higher and the transit is fast -only 1,5 seconds. Be looking at 12:41 pm EST or so. Once again check out for exact times for your location. Once again, proper solar filters for your telescope are required.

Dec 12 solar PE