Comet Jacques Now Sailing past the Constellation Cepheus!
Comet Jacques (C/2014 E2) is now visible through small telescopes and moving fairly quickly across the background stars . In this first week of September 2014 we can see it trace out a line shown above in this finder chart over 4 successive nights . Hopefully he comet will not dim too much so that we can continue to observe it and a new set of positions will be available. This comet reached closest approach to earth Aug 28 2014, so it is biggest and brightest right now! I had the chance on the last night of August to observe this visitor from the outer solar system. The Finder Chart above shows where the comet appears in the sky above our horizon for the next few days. In contrast, the picture below shows the computed orbital trajectory of the comet within our Solar System. We’ll use the finder chart to do the Star Hop and visit interesting stars along the way..
Here is a picture of the trajectory – the cometary orbit proceeds from right to left dipping below the ecliptic plane, swinging past Venus, achieving perihelion late July (not marked), and travelling close to earth late August, early September. This information is courtesy: http://www.livecometdata.com/comets/c2014-e2-jacques/
Observing Report – Sunday August 31 2014 11pm-midnight EDT:
Equipment: Dobsonian Reflector 6” F8 using an 18 mm eyepiece (66X) wide field
Taking advantage of the calm after the Storm Sunday Aug 31, I stepped outside and used my 6” F8 Stargazer Steve, Dobsonian reflector telescope at a modest power to search for the comet . There are so many Open Clusters in this patch of the Milky Way and colourful double and variable stars ! For this observation, I need a low power eyepiece to afford a wide field of view. I used the standard 18 mm eyepiece that gives me a low magnification of 1200/18 roughly 66 X.
Sample Star Hop to Comet Jacques on a particular night
We use the technique known as ‘star-hopping’ to visually locate the celestial object of interest. Star-hopping is the way we use the patterns of the asterisms (groups of stars on the sky map) to move (hop) from one known star position to the next to end up at our target. Once we spy the target in the eyepiece, we can center it and let our eye get used to the dim faint glow of its light. For the comet, the light we are seeing comes from illuminated gas and dust of the body itself. We are seeing Comet Jacques precisely because it is into our solar system and getting bathed in the light of our Sun.
Step 1: (and worth the visit) – From Beta Cassiopeia to Delta Cephei
We are looking through the section of the Milky Way along the constellations of Cepheus and Cassiopeia. They are located above the northern horizon in the sky – North East. Start off the end of Cassiopeia at the star Beta Cas, and sweep your scope (or binocs) towards the ‘upside-down’ house pattern of the constellation Cepheus. On your way you may encounter a very beautiful double star, Delta Cephei. In the telescope, the primary star of the binary system is yellow (this is the pulsating variable star (more on that later)) and the secondary is blue.
Delta Cephei – Delta Cephei – The Model Star is a prototype of the Cepheid Variables – giants whose rates of pulsation tell their intrinsic brightness revealing their true distance. With Cepheid Variables, we can resolve the ambiguity between how bright a star is and how far it is by knowing how these stars periodically vary in brightness.
Step 2 From the Garnet Star (Mu Cephei) Sweep North to Deneb to look for the round faint glow of Comet Jacques
The Garnet Star completes the apex of a roughly equilateral triangle with Alpha Cephei and Zeta at the bottom of the “upside- down” house of the Constellation Cepheus. You can’t miss it once you spy it in the eyepiece as it is very red in colour. This star is a Red Supergiant and like Betelgeuse in the winter constellation of Orion, it is Huge – engulfing the area out to Jupiter if it replaced our Sun.
Comet Jacques – Faint Fuzzy round glow in the telescope eyepiece…
Now for our featured guest this evening – and it is truly a guest because tomorrow night it will move on, and continue to sail on in its orbit. Comet Jacques is on the line between Mu Cephei (the Garnet Star) and Alpha Cygni (Deneb). Sweeping up in the direction shown in the finder map I alighted on our round fuzzy target – a round glow, quite spherical with not much hint of a gas or dust tail. Comet Jacques is faint but large in the eyepiece. On the night of Sunday August 31, Comet Jacques was a third of the distance from Mu Cephei to Alpha Cygni (Deneb). In the next few nights it will continue to sail along through the constellation Cygnus along the summer Milky Way.
Unlike Comet ISON late 2013 (see http://mvc.on.ca/comet-ison-november-2013-apparition) , Comet Jacques 2014 is available for viewing – not very bright, but neither predictably bright either! So let’s take advantage of our opportunity to watch this one before it leaves our field of view.