IC 2220

The Toby Jug Nebula

The first observing night at Ayers Rock was great for some of us and frustrating for others.

All the scopes and other gear were hauled out to the observing site in the daylight so we could scope out our spaces and figure our car parking logistics. An important lesson I learned after the first night was not to set up my scope next to a spinifex bush. This hardy plant is covered with sharp burrs which are impossible to remove from knees, socks or clothing without impaling the sharp points in your fingertips. I just threw away the worst of the spinifex covered clothes afterwards.

Then there was the problem of polar alignment. I had no trouble polar aligning my LITEBOX Dobsonian Reflector. I was easily able to point my scope near the South Celestial Pole (but not exactly on it). One LX200 bit the dust trying to get polar aligned, and the wind dashed the hopes of CCD imaging for these particular star-tourists. For the rest of the trip, they set up their scope at the hotel, in a wind protected spot, and entertained some of the hotel staff and guests with some nice views.

After the first night of astro-tourism, most of us settled down and began to undertake our various projects. I had my project lists just like everyone else, but one object was added. I had never even heard of IC 2220, the Toby Jug Nebula before. But on the long flight from LAX to Sydney, I sat near astrophotographer Bill Williams and his 10 year old son Chad. Chad was looking at David Malin's AAT photographs (naturally) of the southern sky, plus some of Bill's magnificent images taken from Africa.

Chad was wondering if I could help him see one of the objects in the book. It was called IC 2220 - the Toby Jug Nebula.

"Huh, never heard of it. Where is it?", I asked.

"I don't know," replied Chad.

Soon everybody was looking for right ascension and declination, magnitude, anything in their collection of startools. It was the breakfast topic each morning in Sydney.

"Any luck finding tobyjug?" Bill Williams asked the next morning.

"Nope, but John Gross is checking Megastar on the laptop." I replied.

Finally, armed with the coordinates: 07hr 56min 48sec - 59 07' I searched the Southern Sky volume of Uranometria which I had packed. Nearby, just a few degrees south was a nice cluster, NGC 2516 in Carina. Above this object, right there on page 424, at just about the right R.A. and Dec was an object with another number.

"That's gotta be it" Bill agreed.

"Ok, I'll find it tonight" I responded.

The Toby Jug Nebula surrounds a bright but cool star known only by it's number HD 65750. It is the result of light reflected from particles that the star itself has ejected.

Massive cool stars like Antares produce particles which deflect light traveling between stars. The outer envelope is so cool, 3,000 K in this case, that refractory materials such as silicates and metal oxides are able to condense out of the elements created by nuclear fusion inside the star. Other stars produce carbon and carbides and nitrides, but examples of cool stars with visible nebulae are quite rare. IC 2220 gets its name from its likeness to an English drinking vessel, the Toby Jug. It's a bipolar reflection nebula surrounding the bright cool star. The smokey atmosphere of the star further reddens the light seeping through from within. Eventually, as they drift away from the star, the small dust grains will be pushed by stellar winds or pulled by gravity to gather into the cold dark clouds like those seen near Rho Ophiuchi.

This seemed like a pretty interesting project. The research was fun. That second night at Ayers Rock I hunted for the Toby Jug Nebula. NGC 2516 was a beautiful naked eye open cluster nearby. Colorful stars abounded within the cluster. 15 degrees south of Canopus, this cluster alone was worth savoring for a while. Brilliant with several nice doubles, and pretty scatterings of stars, it looked a bit like the Jewel Box open cluster, near B Crucis more commonly known as Mimosa. The red supergiant in the center of the cluster was beautiful. It was fun to have projects in such a gorgeous part of the southern sky! Just degrees away were Eta Carina above, Coal Sack and Southern Cross to the left, and the Large Magellanic Cloud (and Comet Hale-Bopp) below. Whew! What a view! Just happy to be here, became my motto!

I found the star which is responsible for the Toby Jug Nebula. But no nebula was visible! I had to be careful as there were several really bright stars on the upper edge of the cluster. I added an OIII filter, pumped up the power to 202X using my 9 Nagler eyepiece, and a dainty barely visible haze surrounding the star appeared. I couldn't discern the beer mug shape of the Toby Jug naked eye, but could definately see the haze around the star. I don't even know what magnitude to consider the nebula. This is certainly a more impressive photographic object than a visible one. But everyone wanted to see it anyway, since nearly the entire group was in on the research. I showed the cluster first, so everyone got their money's worth.

Next morning I bumped into Chad while I was collecting little tree-frogs for the makeshift terrarium in the hotel room.

"Found it," I reported.

"You did? Cool!" replied Chad.

It wasn't 'til two nights later, when Chad and his dad were between camel sunset rides and astrophoto timing, that he got to find the Toby Jug Nebula by himself thru Strider the 12.5 inch wonderscope. Chad will be giving a report to his classmates in Boca Raton, Florida in a few weeks. He'll demonstrate how to play the didgeridoo (he's very good), show some video highlights of the wonderful experiences he shared with all of us, and I'll bet he'll describe how he starhopped from NGC 2516 in Carina up to the Toby Jug Nebula. Sometimes what you find yourself through a telescope is just as cool as what you see in an astrophoto.