Wednesday, September 20, 2017

a month ago

At this moment, the Moon is very near the Sun. A month ago, it blocked the Sun. What a great thing...

Monday, September 18, 2017

transparency askew

Jack encouraged RASC TC members to take a close look at the Clear Sky Chart pages.

I spotted the warning.

Sunday, September 17, 2017

skies whitened

I followed a thread on the RASC Toronto Centre forum about the white and hazy sky conditions in the Greater Toronto Area. It started yesterday.

It became rather obvious while driving from the north-east...

thoughts after tracking

Some lessons learned from the weekend astrophotography...

The slow-motion control under the barn door tracker worked, sort of. However it does not seem robust. The weight of the camera with grip, the lens, and the tracker itself probably overloaded the small unit. More than once the ¼-20 screw at the bottom came loose! Did it hop a thread? I'll have to inspect for stripping. Also the main tension knob had to be tightened a great deal. It sure was enjoyable dialing in Polaris though...

The Celestron finder scope worked fine. Both nights I simply put Polaris near centre. And that seemed sufficient. But I continue to wonder about how to gauge the true location of the North Celestial Pole. I could try mimicking the entire field of view in software, I suppose...

The top plate is not balanced or does not work in all configurations. For example, after shooting the Pleiades, I pondered the Andromeda galaxy which was straight up. When I moved the camera, the top plate flopped open. The camera cannot hang over the hinge. Perhaps twisting and turning the ball head would let me get to a better configuration but I gave up after brief attempts. At the time, I wondered if a counter-weight would solve the problem. But that seems rather clunky. Maybe it is just a matter of persisting and getting the camera away from the hinge.

The ball head worked really well after the cleaning and lubrication. Fantastic.

I just assumed that the Takumar 55mm would be focused at infinity when I reached the hard stop. It was surprising to find it went beyond.

I had the equipment there but I didn't bother to use it. The netbook connected to the camera would have helped me achieve better focus.

Overall the barn door tracker worked well. The speed knob though is extremely easy to turn. So gets bumped out of position regularly. I need some tape to screw the knob. I will put in the kit box.

I borrowed painters tape for the control knob and the lens focus ring. Need tape onboard for that too.

An extremely long exposure of the Pleiades showed trailing. In other words, I had not dialed it out completely. My workflow is maybe inefficient. Perhaps I should start the other way, shooting for 5 or 10 minutes, and then "working backwards" i.e. when planning to shoot a 1 minute sub. If there's no trailing in a 5 minute then there won't be any in a 1.

Shooting the Pleiades is challenging! It has high dynamic range. So an HDR approach should be taken. A long shot would pull out the nebula. Medium or fast shots will avoid bloating the stars.

I dropped the control unit. Actually, the self-adhesive hook-and-loop strip on the back let go. I dropped the lithium-ion battery. I did not seem to have enough straps and elastics and hooks and lanyards to hold everything to the tripod. Will need more means of secure things.

a better sky (Crowes Landing)

The sky was better this evening. The air was a very pleasant temperature. The Milky Way was brighter, stars lower down showed. Greg and Brent and I looked briefly from the cottage lawn. Later, while the camera robot shot images, rho and I watched the whole sky. She could see more than 6 stars in the Pleiades and was able to spot the Andromeda galaxy. It seemed to me that delta Cep was between zeta and epsilon in terms of brightness. Rhonda wanted some meteors; I saw two. We worked on a few more constellations including Pegasus. We finished the evening looking down! At the stars reflected in the undulating dark water.

Saturday, September 16, 2017

shot with fast lens (Crowes Landing)

Tried imaging Messier 45 (M45) with the fast lens, the old screw-mount Takumar 55mm, f/2.0 lens from my Pentax film system. Atop the boat house.

Continued adjusting the barn door tracker controller speed. Initially racked the focus to the hard stop. But I found it improved when I came back a bit.

Pleiades star cluster

Canon 40D, fotodiox adapter, Takumar 55mm, f/8, manually focused, 45 seconds, intervalometer, ISO 800, RAW, tracking mount, tripod, DPP.


There are two comets in the area: C/2017 O1 (ASASSN) and C/2015 ER61 (PANSTARRS). But I can't see them.

clearer sky (Crowes Landing)

Clearer tonight. Looking good...

Sun setting through less smoke

Shot by Rhonda. Samsung sgh-i337m, Android 5.

stars and planets

I looked up some numbers for Aubrey. From the amazing Wikipedia...

The Milky Way galaxy has a diameter between 100 000 and 180 000 light-years. I didn't realise it was so indeterminate. The number 100 000 had been in my brain last night. But it could be double. That affects my distance remark. Last night I had said that all the stars we could see would be a fraction of 100 000 light years away. I have to revise that to 180 000. All the stars we can see are 180 000 light years or less. And that we are about 25 000 light years from galactic centre, then the (current) furthest extent is 115 000 light years.

Our may contain 100 to 400 billion stars. Wow.

Then I found the note: "There are probably at least 100 billion planets in the Milky Way." That's worded weakly, I think. And it's a number I see as changeable. As our exoplanet research evolves and our instruments get better, we're going to find more planets around stars. As a thought experiment, let's consider the 200 billion stars harbour solar systems and the average number of planets in a solar system is 10, then that means we're in the 2 trillion range.

Milky Way over water (Crowes Landing)

Tried some long exposures with the barn door tracker from beside the boat house while Rhonda took in the whole sky from the dock. Hadn't used my custom BDT for a while. Centred on Camelopardalis.

Cassiopeia and Perseus over Upper Stony Lake

Canon 40D, Rokinon 8mm, f/5.6, manually focused, ISO 1000, intervalometer, 4 minutes, daylight white balance, RAW, tracker, tripod, DPP, GIMP.

Haze from the western wild fires...

Focus is off unfortunately...

Double Cluster is visible. Near the top-right, the Andromeda Galaxy. Cepheus with δ (delta) Cep near maximum.

Friday, September 15, 2017

observing from the dock (Crowes Landing)

Mist over the water.

We did some visual observing from the dock. We watched Pleiades rise out of the murk. We took in constellations and various stars. The Big Dipper was obscured by low cloud and haze or smoke. Fairly clear straight up. We couldn't figure out what was causing the sky glow to the north-east.

Explained that all stars we could see were in our galaxy. And therefore all were less than 100 000 light years, in fact, a fraction of that. Vega was extremely close, 26 light years. [ed: Wikipedia says the size is between 100 000 and 180 000 light years.]

Talked about exoplanets and candidates in the Goldilock's zone. That our current instruments are getting

Helped Aubrey and Rhonda find the Andromeda Galaxy. Used the bright LED flashlight focused to a narrow beam, in lieu of a green laser pointer.

I saw one meteor, a brief slow-moving south-bound traveller.

I pointed out the sleepy fire flies in the grass.

gauged delta Cep

I noted δ delta (Cephei). It seemed to me to be nearly as bright as ζ (zeta) to the left. It was certainly brighter than ε (epsilon).

banded Sun (Crowes Landing)

Just before dinner, we enjoyed the sunset and the weird appearance the Sun took on as it descended through distant atmospheric bands. Wildfire smoke from the west. It looked like Jupiter with the bands.

Sun setting with clouds bands

Shot by Rhonda. Samsung sgh-i337m, Android 5.

signal lost

So long and thanks for all the pix. All the amazing images... The Cassini-Huygens spacecraft was deorbited into the planet Saturn concluding its very successful 13 year orbital mission. I'll miss the incredible new photos of our ringed planet.

Thursday, September 14, 2017

more data on NGC 40 (Halifax)

I collected data on NGC 40 back in August 2016. But I did not gather hydrogen alpha or ionized oxygen. So I queued up BGO.

 FITS Liberator, GIMP. North is up; east is left. For all.

planetary nebula NGC 40 in luminance

Luminance, 10 seconds subexposures, 20 stacked shots.

planetary nebula NGC 40 in hydrogen

Hydrogen α, 30 seconds subexposures, 10 stacked shots. Big and bright! Lots going on.

planetary nebula NGC 40 in oxygen

Oxygen III, 30 seconds subexposures, 10 stacked shots. Round! And compact. Very interesting.

imaged supernova (Halifax)

Imaged SN2017eaw again. It looks much dimmer even from the 11 Sep '17 photo.

supernova SN2017eaw in luminance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. North is up; east is left.

Wednesday, September 13, 2017

returned to M10 (Halifax)

The globular cluster Messier 10 is another object I seem to only have one observation logged. I asked the Burke-Gaffney Observatory to aim into Ophiuchus and capture it.

globular cluster Messier 10 in luminance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. North is up; east is left.

I like being able to see many of the individual members in the somewhat open core. When Chuck Messier logged it in 1764, it described it as "nebula without stars." Ah, no.


Wikipedia link: Messier 10.

Tuesday, September 12, 2017

on the big screen

Enjoyed Tony's videos and stills from the eclipse, while hooked up to the TV. I didn't have a large capacity storage device to take anything...

forwarded an alert

Texted Rhonda with an aurora alert. kp 7.7.

was it Mercury? (Bradford)

Ugh. Up early. Kissed rho and headed outside for the brisk walk to the GO station, dodging skinny kitties and skunks.

Dark again. Winter is coming.

I saw stars! It was very clear. Took in Orion, flickering Sirius, Gemini, Auriga, and the Moon. Tilting my head back, I could see the big Winter Football.

Venus blazed in the east. I noticed something 8° away, below, at a steep angle, about 70 or 80°. Was it Mercury? I know it was near maximum elongation.

I checked Sky Map on the Android smartphone and learned that Mars and Regulus were there too... But which one was I seeing? Sky Map did not show magnitudes.

The point of light faded in creeping fog.


Checked on Grace's iPad in SkySafari. It was Mercury! At magnitude -0.4.

acquired HD 15407 (Halifax)

I wanted to check out multi-star system HD 15407 aka STF 270 in Perseus from one of my "beautiful" lists in SkyTools. I sent BGO on a mission.

multi-star system HD 15407 in luminance

Luminance only, 4 seconds subexposures, 20 stacked shots. FITS Liberator, Paint. North is up; east is left.

HD 15407 is a 4-star system. B is the bright, nearby star to the north-west. C is the medium-bright star north of B. It appears to be moving west, compared to the chart in ST3P. D is the dim star to the west. C and D make a right-angle triangle with B at the apex.

To the north-west lies a faint pair of stars oriented north-south. This is STI1900.

To the south-west is another faint pair of stars. STI1899.

shot 77 Psc (Halifax)

I ordered BGO to shoot 77 Piscium, aka Σ90, a multi-star system. I centred on GSC 00022-0669. From a "beautiful" list in SkyTools, based on an observing list from the Coldfield Observatory,

multi-star system 77 Psc in luminance

Luminance only, 4 seconds subexposures, 20 stacked shots. FITS Liberator, Paint. North is up; east is left.

77 Psc is a 5-star system according to SkyTools.

The B companion is the bright star to the east of the primary. Nearly the same magnitude.

C is the dim partner to the west at 5 times the AB separation.

There is a very faint star to the north-west at the same distance as B. This is the P star.

Q is north of A, about 3x the AB sep. Same intensity as P.

captured nu Cet (Halifax)

BGO captured ν (nu) Ceti. Centred on GSC 00052-0838. A double star from the RASC Observer's Handbook.

I had hoped to catch in the net another pair nearby, to the far east. But PPM 145753 aka PLQ 34 is off frame.

double star nu Ceti in luminance

Luminance only, 2 seconds subexposures, 20 stacked shots. FITS Liberator, Paint. North is up; east is left.

nu Cet B is the delicate dim star to the left or east of the primary. SkyTools says it is 8.1 seconds of arc away.

Monday, September 11, 2017

no data on the supernova

BGO was charged with imaging the supernova in the Fireworks galaxy again but something went wrong. Almost all the data files show registration problems.

quickly viewed the sky (Bradford)

Rhonda and I went to the back yard. The Summer Triangle was straight up. Her memory trick worked as she quoted Deneb, Altair, and Vega. Low clouds in the south but it was fairly clear. She found Polaris.

imaged alpha Cap (Halifax)

I asked Burke-Gaffney Observatory to image the alpha Capricorni multi-star system. That is α1 and α2 Cap. Centred on GSC 05748-2586. The extremely wide pair of bright stars are a wide visual optical double. But each bright star is a multi-star system in its own right.

alpha 2 is at the far left or east-most; alpha 1 is west or near centre.

multi-star system alpha Cap in luminance

Luminance only, 1 seconds subexposures, 20 stacked shots. FITS Liberator, Paint. North is up; east is left.

Due south of α1 is a faint point, possibly elongated. According to SkyTools 3 Professional, this is the location of the B and D stars, both in the magnitude 14 bucket! When I zoom in, I feel like there's a bright point to the north-west and a faint one to the south-east. The HJ 207 C is the somewhat bright star south-west of α1. ST3P also notes an E star, less than 1 arc-second from the primary. Ah.

Below α2, aka HJ 608, slightly east, is a somewhat bright star (although less than alpha 1 C) in a gaggle of faint stars. This is α2 D, aka PPM 721720 and AGC 12.

The little triangle of nearly equal stars to the west-north-west of α1 is HJ 2943. A grouping I had viewed a year ago.

tried for NGC 1528 (Halifax)

BGO shot NGC 1528 for me. An open cluster in Perseus. Just for fun.

Whoa. Something went wrong with the luminance data gathering... (The red, green, and blue channels are OK though.)

open cluster NGC 1528 luminance with registration problems

Luminance only, 30 seconds subexposures, 10 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

I had tried to view this big cluster on the evening of 26 Aug '16 but was clouded out just after slewing.

aka Collinder 47, Melotte 23, and OCL 397. This is considered by many an interesting and fun target. The Astronomical League has it on their deep sky binocular list. It is listed in the TAC eye candy table. It is also a Herschel 400 item.

Given the RGB data is OK, I may try to assemble...


Wikipedia link: NGC 1528.

revisited phi Psc (Halifax)

The Burke-Gaffney Observatory imaged phi Piscium. Centred on TYC 1747 01532 1. This target is in the RASC Observer's Handbook double and multi-star table. It's been on my to-view list for a long time, over 3 years.

multi-star system phi Psc in luminance

Luminance only, 2 seconds subexposures, 20 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

phi Psc aka 85 and Σ99 is a triple. The B star is to the south-west, very close to the primary. Bright but much less so than the host. C is well away and almost due south. Much dimmer. Further along is a slightly bright star, almost inline with C, but it is not related.

Curiously, SkyTools 3 Pro shows B to the south-south-east. It looks like a chart plotting error. It shows it at 163° at 9"...

The WDS says B was at 226° in 1832 at a separation of 8.0"; in 2012 it was at 221 and 7.8. Haas quotes the same numbers.

Far to the east, near the left edge of the image, is a separate double star: POU 113. Both in the duo are faint. B is to the west of A.


Wikipedia link: phi Piscium.

imaged SN2017eaw again (Halifax)

For a third night in a row, the BGO 'bot captured SN2017eaw in the Fireworks galaxy as it begins its decline.

supernova 2017eaw in luminance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

It looks similar to last night.

Sunday, September 10, 2017

clearly dimming (Halifax)

Received another image of the Fireworks galaxy from SMU. The supernova SN2017eaw continues to dim. Seems the same or dimmer than yesterday.

SN2017eaw in luminance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. North is up; east is left.

zoomed on the ring (Halifax)

I asked the Burke-Gaffney Observatory to image the Cygnus Fairy Ring—for fun. A rather large ring of faint stars, many pairs of stars, roughly between γ (gamma) and η (eta) Cygni.

Perhaps not the best subject for BGO as barely fits on the reduce sensor frame. The effect is not as striking as I had hoped. And a couple of the doubles are out of the view.

Cygnus Fairy Ring in luminance

Luminance only, 15 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. North is up; east is left.

Centred on GSC 03150-1379.

North of centre, near the top of the frame, slightly left is the obvious bright pair. However the bright stars are not considered the double star proper. Close and south-south-east of HD 190628 is the much dimmer companion. This couple is also known as PAN 17.

North-west of centre, near the top-right corner, is another bright pair. This time the two stars are related. This is HD 190466 aka HJ 1470.