There may be as many as a trillion comets in our solar system, but only about 5,000 of them have been observed by humans. These small icy celestial travelers often appear suddenly.
Historically, people of many cultures have observed comets and have ascribed good luck or bad luck to them. Approximately once a year, a comet becomes bright enough to see with the naked eye.
A comets brightness is unpredictable in advance since it depends on the amount of gas and dust it releases as it is warmed by the Sun. This same situation makes it interesting to watch as it moves by our home planet. In the spring of 2017 there will be a unique opportunity to view three comets on the same night with a pair of binoculars or with your naked eye.
To do so you will need to be at a location with a natural night sky such as the Cosmic Campground International Dark Sky Sanctuary (CCIDSS). You will need to avoid looking at a white light for at least 30 minutes. Use a fashlight with red plastic wrap attached with a rubber band to view your star chart. If you use a cellphone sky map you will need to make red plastic wrap flter for it as well otherwise, it will blind your night vision.
Comet C/2015 V2 Johnson was discovered by Jess Johnson of the Catalina Sky Survey (CSS) located in Tucson, Arizona. It should be visible in binoculars starting in mid April and may reach naked eye brightness in early June.
This comet is making its one and only trip past our Earth and Sun and then will be leaving our solar system. Eons from now Comet C/2015 V2 Johnson may enter another solar system and appear to any viewers who might be waiting to see it.
Comet 41P/Tuttle-Giacobini-Kresak orbits the Sun every fve and a half years, has a nucleus about a mile in diameter, and is known to have brightness fares. It should be visible in binoculars starting in mid April and could reach naked eye brightness in May.
At the end of April it will pass near the Globular Cluster M92 creating an interesting photographic opportunity.
Comet C/2015 ER61 PanSTARRS was discovered by the PanSTARRS group with their telescope atop Haleakala on Maui. This comet orbits the Sun every 60,000 years or so. It should be bright enough to view with the naked eye or binoculars starting in the mid April pre-dawn sky.
Near the new moon April 26 it should be possible to see all three of these comets on the same night. Take this unique opportunity to view a once in a lifetime celestial pageant.
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3 comets in one night at Cosmic Campground International Dark Sky Sanctuary - El Defensor Chieftain