2015 25th Annual Grand Canyon Star Party - DAY TWO - Cloud Chasing
Location: Grand Canyon Visitor Center, South Rim of Grand Canyon, AZ, about 340
miles north of home in Tucson, about 7000 ft elevation
Weather: mid-70s at Noon, Low 70s at sunset, 50s when we quit near 00:30.
Increasing cloudyness during the day, Moderately obscured when we came out
after the night talk, gradually cleared to about 90% open.
Seeing and Transparency: OK, not great due to the moisture pumping in now that
the Colorado high pressure zone has started to transition to monsoon state. I
worked all night at f/5, about 310X.
Equipment:
18â f/5 2286mm Teeter Telescope newtonian truss dob, Sky Commander DSCs
(unused due to some equipment issues)
10" Meade SCT on Atlas EQ-G mount
Mallincam Xterminator video system on the 10", 19" QFX LCD monitor.
We started off the evening with a talk by my long time observing partner, John
Anderson, on the development and classification methodology for galaxies.
Always seems to entertain the audience, pitching the subject at just the right
level. After he completed the talk the audience was highly involved with
asking very good questions about the nature of galactic development as well as
how we study the structure of space, and the distances involved. Although John
only talks for about 20 minutes, the questions often run over half an hour.
LOTS of education going on.
The 10" was set up and showing a gorgeous Venus by the time we had to run in
for the night talk. However, during the talk, the power line to the mount head
had an intermittent interruption and restart, so it had lost its home position
and alignment knowledge when I came out. I did a quick education session with
granddaughter Karina who was picking up the sope operation using a bubble level
to get the weights down and latitude setting correct, then used the mount
controler to give the correct Polaris position for polar alignment. I used the
polar scope, performed a two star alignment, it put the second star right on
the cross hairs of the alignment mask in the video display, so in 15 minutes we
were ready to do our share.
First target was M82 in Ursa Major (some catalogs call this one and M81 Bode's
Nebula, some call it the Cigar Galaxy). I zoomed it by 2x, and every 30 second
cycle it got better and better in detail. The audience was quite intrigued by
the nature of this irregular galaxy, and after about the third refresh the
hydrogen emission zone on one edge was very pronounced, so we could talk quite
a bit about this particular item, although thinking back on it, I could have
gotten even more detail by reducing the integration time by about five to eight
seconds. Still, the end to end detail changes were eliciting many great
questions from the passing audience. A lovely, almost cloudy, outer ring of
the cigar shaped item, with the denser inner core capped by the emission layer
plus the mid-band of out of visible range energy generation giving a good
enough image to take it as it was.
After some time on this object, John Anderson walked by with his wife Karen and
wanted to see M51. Crossing my fingers, I enetered it into the hand controler
and it came up dead center. With zoom = 2, it filled about 3/4 of the 19"
monitor. I pointed out to the rest of the crowd how long a duration this
interaction between this giant spiral and a smaller galaxy has been occuring.
I've heard that the smaller member passed behind the large spiral as long as
20+ million years ago. The signature is in the outer arm of the giant, on the
side of the smaller partner, is flattened away from the little one. This
implies that at some time the smaller galaxy was close enough to the core that
its gravitational influence deformed the outer arm toward the core of it's
parent. Now the little partner is on the opposite side of that arm, and while
some observers point to the conncection between the two galaxies, I couldn't
really detect much current star formation in the stream, which, if the gas was
being currently compressed, should be more prominent. Anyway, that's just my
opinion. Still running with Amp Gain Reduction off, I did up the integration
time to over forty seconds to pull a pleasing image out.
In the meantime, among the passing crowd, we got the usual general questions
about the sky denizens in general. Hera, being jealous of Zeus fathering the
illegitimate child Hercules, drove him to insanity and he murdered his family.
To attone, he was tasked with the 12 labors of Hercules, one of which being the
slaying of the Nehmian Lion (sometimes thought to be Leo). The Lion was
thought to be indestructible because of his incredible hide, but Hercules, born
to be the strongest human ever to live, jumped on the back of the Lion and
strangled it, clevely using it's own claws to cut the hide away and use it as
protection for the rest of his labors, while stripping out the lion's head and
using the skull as a helmet.
After hearing this story, and another I was relating about the genesis of
naming the star in Canes Venatici Cor Caroli following the death of Oliver
Cromwell and re-establishing the British monarchy under Charles II, whose
father Charles I was a casualty of the Cromwellian revolution. As a result,
the namer was granted something on the order of 300 British pounds a year
stipend. I am looking for the Bill Gates Cluster! So, hearing these stories,
I had a magazine editor hunt down a Ranger and introduce us, and she wants to
talk about popularizing the night sky. WAY COOL!
We shut down about midnight, ending a very nice night with the visitors thanks
to the magic of the Mallincam Xterminator. Monday night I'll do the night
talk, called What's Up There, a little bit about every thing we study in the
night sky. Then out to tonight's targets, Karina's favorite planetary nebulae
which she teaches so well. I'lll be in the shadows in case she needs an assist
on the Xterminator, but tonight is her night to be the star.
One last thing...Gary Fix teaches celestial navigation and sextant use on
cruises and other venues. He has set up to do sextant lessons to visitors out
front of the visitor center during the day, and we have him set up for the
astronomers to do a great presentation on the use of astronomical references,
especially true north lines, in the construction of Italian cathedrals. Every
year we get better and better!!
Jim O'Connor
South Rim Coordinator
Grand Canyon Star Party
gcsp[at]tucsonastronomy.org
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