Sunday, July 02, 2017

gas giants and ducks (Blue Mountains)

Threw a mini star party for amazing Aditya.

9-ish PM. We started with some quick unaided-eye observing from the back step of the Carr Astronomical Observatory house: the Moon, bright Jupiter to the right, and below, sparkling Spica.

From the Geoff Brown Observatory, we aimed at the first quarter Moon in the Tele Vue 101mm and the Celestron 14-inch. Good detail along the terminator. Fair seeing conditions. Briefly I wondered when Lunar X was visible. [ed: Mitsky said: the "X-shaped illumination effect involving various rims and ridges between the craters La Caille, Blanchinus, and Purbach, is predicted to occur at 8:57" UT.] It looked to me that we were hours or a day or two past the period it would normally appear... I reminded our guests that the Moon would look good in their little 2" refractor. And they'd be able to see the Galilean moons.

Happy birthday Galileo!

I noticed the human door of the garage open and the white lights on. Oops. I excused myself, extinguished the bulbs, and closed the door.

We looked at Jupiter. Adi's dad enjoyed the cloud bands. I grabbed my netbook so to ask SkyTools to ID the moons. Io and Ganymede were close together on the east side of the gas giant; Europe opposite, about the same distance as the other pair; way out: Callisto.

Clouds appeared. Sporadic. Not great; better than rain.

The groups returned from the fireworks displays.

We viewed Saturn. Shame it was so low for the view was mucky. Still, despite the poor seeing and refraction, I immediately saw Titan. On lingering, I saw many more moons. Rhonda was thrilled to tag Titan to the south, Rhea to the south-west, Tethys (likely not Enceladus) to the west, and Dione to the south-east.

10:29. I viewed Saturn in the TV101 and C14. I had the 10mm ocular in the refractor and the 27mm in the SCT. I could see Titan in both.

Turned to Albireo in the Swan. Asked the young lad about the colours.

In the Warm Room, I pointed out the Aquila pattern. Adi thought the constellation stick figure looked like a stingray. What a great new constellation!

The clever lad was interested in seeing more planets. Mars was out-of-season. I checked Neptune and Uranus. They looked to me very late-night slash early-morning targets. Assured him we could really see them in our big telescope--but they'd be very small. Obvious, but small. That didn't deter him but I was not confident that even I could stay up that late. How 'bout Mercury? We did a little orbital diagram with hands and he realised it would be impossible to see now. Of course, he wanted to see Venus. I said I'd me fast asleep at that time. But if he wanted to wake before dawn, it would be amazing.

I put the Paramount ME on the Wild Duck Cluster. Messier 11 was lovely in the small refractor, a tight cluster in a black field. M11 resolved easily into hundreds of stars in the big gun. I had to differ with Aditya. Not millions of stars. But if he wanted to see something with a half-million stars, we could head over to Messier 13.

Rhonda rounded us up for Canada Day cake. Very yummy. White cake with whipped vanilla icing and strawberries in the flag pattern. I would have had a second piece but I was not feeling great.

Put on a sweater, jacket, and light gloves.

The Milky Way was barely visible from the back step.

When we returned to the GBO, I dove into the SCT ocular. My first impression was that it was wildly out of focus. Didn't make sense as no one would have touched it. As I turned the mirror-moving knurled focus knob, I immediately realised the issue: dew! The 'scopes were aimed up high and I had not installed the dew cap. Oh oh. I swiped a finger down the OTA and lamented the dark trail.

But why wasn't the dew being cleared by the removal system? From the ladder, I could see the corrector plate was fogged so I grabbed the hair dryer. Ian D helped me install the cap after defogging the glass.

I checked the Kendrick controller and noticed the output channel 1 and 2 LED indicators (the C14 and TV101 heaters, respectively) were not illuminating! What? That's why we were getting dewed out--the heaters were not even on! Very strange: channels 3, 4, and 5 were working.

Grabbed the user manual. Asked Rhonda to hold up the red flashlight. I dove through the menus trying to energise the heater straps to no avail. Finally I gave up. I was feeling bad for our visitors but when I turned around I found the GBO empty. Rhonda said everyone was going to bed. While frustrated, I was relieved that I didn't have an anxious queue of guests.

I was doubly relieved as my voice was giving out, my throat was sore, my shoulders ached from coughing. Stupid cold.

Asked rho if she wanted to spy the supernova in the Fireworks Galaxy. Slewed to Cepheus.

Could not see the face-on spiral galaxy at all but centred on the space between the big L (or triangle) with TYC 04246-0221 1 to the south and the wide pair with TYC 04246-0473 1 to the north. Downloaded one of my SMU BGO images and flipped it. I spotted the pair of stars oriented north-south and the star to the left or west. And beyond, the equally bright type IIP SN 2017eaw. After carefully explaining the view to rho, she saw it too.

Sketch of field stars surrounding the supernova. North is up; east is right.

22 million light-years away. That blew her mind. And it blew her socks off.

I was really, really done. Not feeling well. No interest in proceeding. No energy to fight the dew issue. Rhonda helped me close down. Decent sky as we walked to the house.

From bed, I reported the dew heater problem.

Grabbed the weather data (a little late):

1:32 AM, Sunday 2 July 2017. Local conditions via the Davis weather station unit.

10 minute average wind speed: 8.0 km/h.
From the west-west-west-north.
High wind registered at 19.3.
Humidity was 98%. Indeed.
Barometer said 1012.5 hPa and rising. Yeh!
The outside temperature was 13.2°C.
With a wind chill of 12.8. It felt much colder to me.
And, finally, the dew point was calculated at 12.9.
Yep. We had definitely gone below it.

So, a reasonable evening at the CAO. OK skies. Session ended a bit early. I don't think anyone was irked though. I was worried I had frustrated people with our dew troubles and my lack of energy. It all worked out.

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