Saturday, September 19, 2015

checked elevations

We talk about the lunar eclipse. Elaine and Tony wondered about sight lines. I checked SkySafari. The Moon would be about 20° up when the umbra phase began and about 40° up when it ended.

wax and wane (Caledon)

Cleared up on the drive home. But at the same time, Elaine noticed that the stars were disappearing: light pollution. We saw the Moon, Saturn, Antares, The Teapot, and other stars. Saturn, Antares, and the Moon were in a triangle. We enjoyed the view as the clouds dissipated, before the orange glow took over. We thought of Richard at the observatory. Hopefully, he was getting good skies.

noticed the sign

Spotted the lunar eclipse notice at the L.E. Shore Library. Please join us at the Carr Astronomical Observatory.

Monday, September 14, 2015

incredibly clear (Blue Mountains)

Clear outside. Finally! Too bad everyone had left!

Brought out my netbook. Ian helped Tom collimate his Newtonian.

Dietmar set up his Star Adventurer, at last.

Millie set up. I was curious how she'd fair with Phil's updated notes.

Inspired by Risa, I made a list in SkyTools 3 Pro of the autumnal Turn Left at Orion objects, non yet viewed, some 15 targets!

Missed my socks! Turned on the baseboard heater.

8:01 PM Sunday 13 September 2015. Viewed Saturn. Lovely.

Some clouds showed up... Still, it was the best night I had seen in a while!

8:07 PM. Slewed with SkyTools. Nice... Working well. A simpler set-up too, frankly. Running without the RASC laptop.

Tom and I saw, in the Celestron 14-inch SCT, Titan, Rhea, Dione, and Tethys. Tried for Iapetus.

8:26. Checked the local weather conditions from the Davis weather station. The 10 minute average wind speed was 4.8 km/h. Down significantly from earlier in the day. The wind direction was WNW. The immediate speed 3.2. The high had been 40.2. The humidity was 88%. The barometer was 1011.6 hPa. The outside temperature was 10.3°C. Brrr. Socks! The predicted dew point temp was 8.4.

8:38. Tom and I spotted Iapetus finally. It was tricky. Nothing nearby. Saturn sinking. Currently at 3.5 air masses.

Dietmar exclaimed he could see several stars on his mirrorless camera view screen. The wonders of sensitive chips and high ISOs.

8:42. I rotated the eyepiece. Got it again, Iapetus.

8:50. The transparency looked really good. We could clearly see the Milky Way already. And the sky was not dark!

8:55. Viewed the multi-star system HD 164492 in the middle of the Trifid. A and C were easy. B was to the left or north, much dimmer. The ST3P chart showed them being the same brightness; but the Object Information said the magnitudes were 7.2 and 10.4. I agreed with the latter.

The nebula was visible. I could see the dark lanes. All three.

8:58. Spotted G. About 3 times the distance of the AC sep. To the right or south. ST3P said it was 13.2. Certainly it was tricky.

9:01. I saw the D star. It was not at a right angle to A and C. The CV chart said 7.1. No way; OI said 10.5.

Could not see E or F.

9:06. Tried the O-III filter, in the 55mm. It was a little hard to use, in the bright room. Also, it was smaller now, from the 27mm. Nice.

9:12. Went to γ (gamma) CrA. Dietmar asked, "Are you going for groundhogs?" No doubt.

Goofy. Just a coloured jumpy blob.

Ian popped in. He agreed the transparency was good.

9:24. Dietmar said the tracker and camera were working. He was happy with the results so far.

Incredible sky. The south-west was very clear. Could see Saturn just about the trees. 

9:43. Malcolm P phoned and was surprised someone was around. Leaving Midland. Asked if he could come by. Sure!

9:44. Viewed ζ (zeta) Sgr aka Ascella. Saw C no problem. Possibly I saw A and B, bright white stars, in a 70 degree alignment. Very tough. Started in the 27mm and then the 18mm. Very close. Seeing was not great.

[ed: Ascella is a fast-mover according to SkyTools with a 21 year orbit! ST3P calculated the separation of A and B to be 0.59" in July. The Object Information dialog showed the magnitudes as 2.6 and 3.5 respectively; Haas says 3.3 and 3.5. Ascella is listed in TLAO as a jumping-off point for locating M54 and M55. No mention of it being a double star... Haas noted the separation as 0.2" at publication.]

9:56. Tried to split AB ρ (rho) Cap. Not steady enough. Tried the 5mm in the TV101. No prob for C, D, and E stars. Saw many field stars.

10:31. Viewed 51 Peg. It was a light orange. [ed: A G5-class star.] Not a lot of comparable field stars nearby.

10:35. 51 Pegasi is magnitude 5.5. A suspected variable according to SkyTools. But not a lot of variance. Took the 5mm out of the 101; put the 55mm in. 51 was about the same brightness as 45 Peg (6.3). It was brighter than HD 216625 (7.0).

[ed: Guy Consolmagno refers to this "featureless" star in a "bleak" field simply because it was the first star shown to have planets. Removed from my View Again list.]

TLAO said M15 was in the neighbourhood. ST3P showed it out at the legs of the horse. OK, had a look. A nice big glob with the 27mm. A bright star nearby. That was HD 204712 at 7.6.

Helped Dietmar aim his camera at M31.

Ian helped me find with M8—the Lagoon—naked eye, above the spout, before reclining. Above the spot of the Teapot.

Malcolm arrived. He was interested in imaging the northern sky. Hoping to catch aurora.

11:11. I slewed to Neptune hoping to find moons.

Tried to spot Messier 33 with Ian with the Mark I Eyeball on the Observing Pad. Nope. NGC 752 was easy...

12:13 AM, Monday 14 September 2015. Couldn't see any moons around Neptune.

12:16 AM. Slewed to ρ Cas. Viewed in the TV101 with the 55mm. A pale orange citrus star. Noted V373 to the left or south-east. And a large round fuzzy with a bright centre to the 10 o'clock position. That was NGC 7789. rho was brighter than HR 9059 and σ (sigma) Cas and brighter than τ (tau) Cas. [ed: ρ Cas varies between 4.1 and 6.2. V373 varies between 5.9 and 6.3. HR 9059 is another suspected variable around 5.6. tau is a suspected variable around mag 5. sigma A is mag 4.9.]

12:24. Fantastic colour in the C14: intense light yellow-orange.

Saw the double STI3051A to the west. ST3P made it look like a triple on the chart; only a double. A was orange-ish, B blueish. A was brighter than B by a fair amount; opposite what ST3P said. [ed: ST3P says A is 11.8 and B is 11.4. No.]

Spotted a neat arc of 4 stars to the east near V373 Cas. With GSC 04009-0727.

TLAO said ρ Cas "may be on its way to becoming a supernova." That'd be neat!

Viewed the Sailboat Cluster aka NGC 225, Collinder 7, OCL 305. All equally bright stars. I wondered how it got its name. Was it the arc of stars in the east? Turned the mirror diagonal different ways. Was the curve the hull or the spinnaker?

12:41. Millie exited the GBO.

12:45. I noted a little triangle on the north edge of the cluster that ST3P referred to as HJ 1046. Similar brightnesses [ed: 10.9, 11.2, and 10.8, in the OI box]. AB were oriented east-west; C was at a right angle to A-B.

12:52. Took in NGC 436. [ed: aka Collinder 11, Melotte 6, Raab 2, and OCL 320.] Mostly pale blue stars, many fine faint stars. Lots actually. Three brighter stars running east-west nearly equally spaced. It was fairly large in the 55mm in the C14. Noted a yellow star to the west, HD 7284, in an arc.

1:01. Put the 27mm back in the C14 and the 10mm back in the TV101. Saw STI1550A the triple in the middle. A and B similar, C fainter, harder, perpendicular. Saw the double BD +57 00230 to the south-west, well away. [ed: aka LYS 2. I don't know this designation.]

Slewed to NGC 654. Neat cluster! [ed: aka Collinder 18, Melotte 9, Raab 5, and OCL 330.]

1:07. Noted a wedge shape. One bright star. Lots of doubles within, 6 pairs or more. And a triangle to the north.

1:13. Found STI 277A on the east edge. A was much brighter than B. Saw STI 275 A, B, and C. North of centre. A and B were close and faint. C was brighter. Noted STI 276A. To the north-east of centre. Again B was brighter than A. [ed: In the IA chart, ST3P showed A as 13.2 and B 11.7.] Saw STI 274 A and B but it looks like C had moved eastward... 274 was also north-east of centre but closer. Looked like there should be more! It was fun. But tiring.

1:22. Viewed NGC 559. A faint cluster. Fairly small. Streamers or fronds arcing out. It too had a number of double stars.

Could not coax out any moons of Uranus.

1:45. Closed up. Tried to do as much as possible. To support a get-away tomorrow. [ed: Er. Late in the day...] Headed to the kitchen to unwind.


Wow. I didn't think, at the time, that I did much. When in fact I viewed 23 objects. A number of firsts. Some revisits. And knocked off a few from the TLAO Autumn list of course. Nine remain. A beautiful night.

Tuesday, September 08, 2015

wired up camera heater

Wired up one of the new pulse width modulation control units. This will be the camera lens heater. It can also be the isolated finder scope heater.

Found all the needed parts in my various bins. Made sure of the polarity on the input side.

Secured the wires to the side with a nylon wire clamp and brass screw (from the barn door tracker extra bits). Had to open the control box. Not much inside!

Monday, September 07, 2015

simulated a photon

Watched the Riding Light video on Vimeo by Alphonse Swinehart. He simulates hitching a ride on a photon as it leaves the Sun.

Riding Light from Alphonse Swinehart on Vimeo.

It gives one a powerful sense, over 45 minutes, of how big—and empty—the solar system is. And that's just to Jupiter!

volatile skies

I was a little disappointed leaving the CAO today. Overall, the weather was OK but not good for astronomy. Almost every evening slid into high wispy clouds overhead and haze on the horizon and bad seeing everywhere. I had hoped to do some double star imaging but it was not to be.

since I'm up

House phone rang. No one there.

Took a peek outside. The prediction had said clear after 2 AM...


Sunday, September 06, 2015

no go for CAO

Waved off Pamela's group again. Felt a bit bad but in the end I think it was a good call. The skies were not good.

Saturday, September 05, 2015

tuned tracker

Aligned the barn door tracker, after a lot of effort and fiddling.

Realised my mistake after some effort. The finder scope can NOT be on the bottom plate, at least to ensure the finder is colinear with the hinges. Back to the top plate. What would I do with all this space on the new rectangular bottom plate. Huh. Lots of room for the control unit...

Version 3?

Shimmed the finder scope to angle the nose up.

Tried, once again, to tighten the tiny set screw in motor gear. Gah. Very frustrating. Worried about loss, I put a bailing wire piece through the shaft. At least now the gear won't go astray.


Thomas was very interested. Offered it for him to try in the evening. Sent him some of the key building notes. Checked with Ian W to see if there are any kits left.

saw small spots (Blue Mountains)

Viewed the Sun in full spectrum (in the C14) and hydrogen-alpha (in the TV101).

Sunspot 2411 was obvious. informed me of 2409 which I found with a bit of effort.

reassembled BDT 2.0

Reassembled the barn door tracker version 2.0. Looks good.

Still cannot tighten the small gear to the motor shaft. The Allen grub is less than 0.050" and 1.3 mm!


Searched the web for small keys. There are some. Down to 0.7mm!

Friday, September 04, 2015

ran sky tour

Offered an impromptu sky tour for Erna, Debbie, and John. Anne too. I was grateful for Katrina and Phil's help. We got lucky with the conditions.

repaired CAO Dob

Decided to have a look at the Walker Dobsonian. I had in mind to loosen the turntable and have a look at the sticky focuser. Of course, it became a bigger job.

The rocker box turntable bolt-nut was so tight that without the optical tube assembly, the top would not turn freely. With 17mm wrenches, I loosened the pivot fastener one full turn. It is much better azimuth. But with the weight of the OTA, it stiffened again. I wondered if the slide-y bits need to be checked.

I moved on. As I checked the altitude, I noticed the side elements on the OTA moving. Oops. I found the two bolts very loose. When I looked down the tube, I saw the nut on one bolt was at the end of the threads! Crikey. That would have been bad when it fell off... I put a 10mm spanner on the nuts and a large Philips on the bolts and tightened them. Good. The other side of the OTA was fine. Much better altitude motion now. Still, there's a lot of play in the handle area. I wonder if a shim has gone missing.

Finally, the focuser. Sticking and jumping when at the out position. And not because the lock was engaged. I dismounted it recalling memories of fixing the Centre's other Dob focuser last winter. Gum-like grease again! Ooh. This focuser did have the sled! I had wondered about this last December! Black plastic (Teflon?) about 4 or 5 cm long, with divots for the two small hex grubs. Cleaned everything with paint thinner. Apply white lithium grease to the rack-and-pinion. Reassembled. Much better!


Clouds. No aurora.

Thursday, September 03, 2015

mysterious Moon (Blue Mountains)

I noticed a warm yellow blob to my left, just over the hill. Moon's up. And very enigmatic behind streaming clouds.

better but

Best sky so far but still far from good. Clouds all over. Pot of the Big Dipper missing. Nothing below Cassiopeia. Big cloud in front of Aquarius. The western sky blotted out below 45 degrees. Stars overhead were twinkling. Everything dim. There was a lot of reflected light from Collingwood. The Moon would be coming up soon...

started the finish

Dismounted all the bits from the barn door tracker. Sanded and filed. Finally started the finish. Set to dry atop custom stands.

Acrylic polyurethane quick dry wood finish from Home Hardware. So to protect the baltic birch.

Wednesday, September 02, 2015

worse tonight

Wondered if I might spot a deep hued Moon again tonight. Checked Moon set time on the RASC caleendar and SkyTools: 10:22 or so.

9:04 PM. Hazy. Diffuse light in the south, like car headlights in a foggy road. Some stars overhead but nothing low. Felt very humid.

Started up the DVD player and projector. Time for a horror movie.

Spotted a meteor, ironically. Fast, westbound. A Perseid? But the angle didn't seem right. Maybe a Cap?

9:25. Terrible conditions. Only three stars were visible in Ursa Minor.

Back to my horror movie.

11:30. The Moon was up but covered by clouds. I could only see a faint glow in the east.

Almost completely clouded over when I went to bed.

updated BDT to 2.0

Revised the barn door tracker. This is version 2.

Switched to the new bottom plate. Simple rectangle. Same width as the existing top plate (6-1/2" but much longer (12").

The drill press made easy work of the through-the-plate passages and the various screw pilot holes. I made the critical measurement, as per Gary Seronik's instructions, for the bent rod: 6.9 inches plus the distance to the centre of the hinge (3/32): rounded to 7.0". And this time, I countersunk the opposite side to reduce binding.

I wanted the larger plate for a few reasons: to protect the exposed main gear; and to offer space for the finder scope. Even though the finder and bracket aren't that heavy, this design reduces the weight on the top plate. And helps avoid collisions with camera bodies or lenses.

Finally, with the table saw, I made a octagonal spacer with some of the scrap birch plywood. This is to elevate the ball head, which in turn will raise the camera body to, once again, avoid collisions between body and top plate, particularly when trying to aim straight up.

Of course, the whole thing is bigger and heavier now. No longer fits in the corrugated cardboard box I've been using. Oh well.

Ready for aligning the finder!

Tuesday, September 01, 2015

red Moon rising (Blue Mountains)

Looked outside a few minutes ago. Few stars were showing. Mind you, I was not dark adapted. Still, few stars were showing below 45°. Hawkeye Ian could see some at 30°. Cygnus straight up. I looked left. Oh. A dark red Moon was rising over the east hill. Another tell of the smoke in the air...

checked washers

Checked the fastener hardware for Tony for one of the potential work party jobs. Measured the washers. We intended to cut the middle post of the west GBO roof rail.

replaced belts

Ian W and I repaired the Stargrazer mower. New front and rear drive v-belts.

I had seen the cracks in the rear belt before. But once out, it was clearly in bad shape, with a 15mm chunk missing...

Also had a good look at the deck lever. Back in operation!


Discovered one of the belt guide pins at the motor pulley was missing...