Pluto (2016/06/15)

This animated image shows the movement of Pluto in 2 days.

On 6/15, I took some images of Pluto at Coe after I completed my main object. However it was very windy on 6/17 and seeing was not good, so I had to abort my main object plan, instead I took some images of Pluto then packed up. Due to bad seeing on 6/17, the stars looked much larger and blurry than 6/15.


Date: 06/15/2015, 06/17/2015
Location: Henry Coe State Park, Morgan Hill, CA
6/15: very good transparency, excellent seeing;
6/17: very windy, excellent transparency, bad seeing
Equipment: AT111EDT on CGEM, guided by OAG-8300/ST-i, STF8300M+FW8+Baader LRGB
Exposure: L – 300sx5 each, Dark/Bias/Flat calibrated
Software: Pixinsight

2008/02/20 Total Lunar Eclipse

The sky was mostly cloudy (sometime the Moon was completely clouded out) throughout the entire eclipse. I took some pictures with my digital camera on tripod at my backyard, so the Moon appeared blurry with long exposure.


This is 8-pane composite from mid total eclipse to the forth contact.


19h41m, 8s @ ISO 400
Total eclipse


19h50m, 8s @ ISO 400
Total eclipse

Location: Sunnyvale, CA
Equipment: Panasonic DMC-FZ18

Partial Eclipse Begins: 17:43:19 (not visible)
Total Eclipse Begins: 19:01:10
Greatest Eclipse: 19:26:05
Total Eclipse Ends: 19:50:57
Partial Eclipse Ends: 21:08:47

2014/10/23 Partial Solar Eclipse

Partial Solar Eclipse happens when the Moon and the Sun are not completely aligned, so when viewing from the Earth then Sun is partially blocked by the Moon. Though not as specular as Total or Annular Solar Eclipse, it is still a fine  (and sometime unforgettable) astronomical  event.

On Oct 23rd, much of the North American is rewarded with a Partial Solar Eclipse, with  the maximum magnitude of ~0.8 at northmost area of Canada. The time is most preferable for Westen US as the entire Eclipse is visible, however Eastern US has the opportunity to view the eclipsed sunset which could be very spectacular. In San Francisco Bay Area, the eclipse starts at 13h54m, ends at 16h33m, and the greatest eclipse occurs at 15h17m with the magnitude of 0.5.

The weather at this time of year may be either very good or very bad, since the rain  season is about to start. On the eclipse day, the sky was partly to mostly cloudy in the entire morning, however the overall weather during the eclipse was good, there were some very thin high clouds at the beginning of the eclipse and then sky became mostly clear until end of eclipse.

I decided to use my “grab and go” setup for this event, which can be set up or torn down in less than 10 minutes. I set it up on the sidewalk outside my house, where the Sun would be visible throughout the entire eclipse.

This is the composite which consists of 18 individual images with 10 minutes interval.


In the following image taken just before the 1st contact, there were 5 sunspot groups in the Sun. Jupiter sized sunspot AR2192 – the largest sunspot since 1990 – was easily visible by naked eyes through the solar filter. The Sun image on the same day by SDO (spacecraft) was also attached for comparison.


13h51m01s, 1/3200s @ ISO 400


Sunspot by SDO

At 13h54m, the Moon crept in from NE, the 1st bite of the Sun was visible in the image but not to naked eyes yet.


13h54m02s, 1/3200s @ ISO 400
First bite

AR2193 was being covered by the Moon at 14h21m.


14h21m38s, 1/3200s @ ISO 400

As the eclipse progressed, more and more Sun’s disk was covered by the Moon. At ~14h45m, the temperature became noticeable cooler and the weather was more pleasant (since I had to sit under the Sun all the time). The magnitude was ~0.4 at this time, and >25% of the Sun’s disk was blocked. The weather remained cooler until 15h40m, when the temperature gradually increased, and returned to normal at 15h45m.


14h45m02s, 1/4000s @ ISO 400

At 15h05m, sunspot AR2193 emerged from the shadow of the Moon, after disappearing for 44 minutes. In this image (and many others too), many details of the sunspot AR2192 can be seen. It is amazing that my portable telescope (72mm F/6) could deliver such high quality image even under far from perfect seeing condition (seeing is the stability of the air, bad seeing usually occurs after the cold front sweep across and will result in the blurry image).


15h05m03s, 1/4000s @ ISO 400

The greatest eclipse occurred at 15h17m, ~40% of the Sun disk was blocked, with the magnitude of 0.5 (which can be measured from the image).


15h16m58s, 1/3200s @ ISO 400

The Sun at 16h15m, only a small portion of the Sun remained being blocked by the Moon.


16h15m01s, 1/4000s @ ISO 400

At 16h32m, the Moon was about to move out completely, only a trace of the shadow was visible on the left (West) in the image.


16h32m00s, 1/4000s @ ISO 400

Eclipse begins: 13:54
Greatest eclipse: 15:17
Eclipse ends: 16:33

Location: Sunnyvale, CA

– CG3 motorized GEM mount and tripod
– AT 72mm ED
– Baader solar filter
– Canon T3i camera

2014/04/15 Total Lunar Eclipse

This is the first of a series of 4 consecutive total lunar eclipses visible from US in year 2014 and 2015. This is also the best one for west coast because the Moon is near the culmination at the greatest eclipse. The weather did not cooperate though (as one would always expect), the high cloud partially blocked the Moon almost throughout the entire eclipse; towards the end when the high cloud was about to move out, the marine layer crept in. However during the total phase of the eclipse, the sky cleared up for a short period of time (~20 mins) to show off the beautify of the sky – the red Moon hugged by the red planet Mars and the blue bright star Spica.

I setup my telescope at my backyard due to unfavorable weather. My sons also invited some of their friends to our house to view the eclipse.


Lunar Eclipse Composite


Totality Composite

Red Moon Composite

People also call Total Eclipse “Red Moon” because the Moon looks red or orange during totality. Arguably, this is the most reddish total eclipse I have ever seen, it is deep orange red during totality, as shown (though not exactly the same color) in the following picture taken near the greatest eclipse.


00h52m03s, 5s @ ISO400, Manual WB)
Blood Moon

Red is not the only color in total eclipse, believe or not, there is also blue color if you observe carefully. As explained in this link, “However, light passing through the upper stratosphere penetrates the ozone layer, which absorbs red light and actually makes the passing light ray bluer.”. “The blue color — which can sometimes be seen on the rim of Earth’s shadow against the moon — is best observed through a small telescope or binoculars during the first and last moments of totality”.


00h03m38s, 1s @ ISO400
Turquoise Moon


00h05m37s, 2.5s @ ISO400
Turquoise Moon

A few more pictures which highlight the progress of the eclipse.


23h28m06s, 1/250s @ ISO400
Half Moon and Crater Tycho


23h55m43s, 1/2s @ ISO400
Crescent Moon and Earth Shadow

The time of the eclipse:
The 1st contact: 22:58:19
The 2nd contact: 00:06:47
The greatest eclipse: 00:45:40
The 3rd contact: 01:24:35
The 4th contact: 02:33:04

Location: Sunnyvale, CA
– AT111EDT
– AT72ED
– Canon T3i

Comet Panstarrs (C/2011 L4)

C/2011 L4 (PANSTARRS) is a non-periodic comet discovered in June 2011 that became visible to the naked eye when it was near perihelion in March 2013. It was discovered using the Pan-STARRS telescope located near the summit of Haleakalā, on the island of Maui in Hawaii. Comet C/2011 L4 probably took millions of years to come from the Oort cloud. After leaving the planetary region of the Solar System, the post-perihelion orbital period (epoch 2050) is estimated to be roughly 106000 years. Dust and gas production suggests the comet nucleus is roughly 1 kilometer (0.62 mi) in diameter. (from Wikipedia)


My original plan was Windy Hill on Skyline, but I did not have time so I stopped at bayland park trail near HW237. The sunset looked beautiful but that was a bad news , as the “beauty” came from clouds that covered lower sky from SW to NW. Anyhow I took a few pictures, even though I did not expect to capture the comet. Today when I checked , to my surprise I saw the comet behind the cloud. The core was bright and a very short  fan shaped tail seemed barely visible. I also setup a binoculars but could not see it visually.
I wish I had stayed longer (I left at 7:50) and captured more photos.

The following 3 photos were taken at 19:47, 19:50, 19:55, with Canon T3i and 70-200mm nikon zoom lens at 70mm. ISO: 400,exposure time: 1s. Cropped from original, no post processing.


Panstarrs at Suntset


Panstarrs at Suntset


Panstarrs at Suntset


Late afternoon Cirrus clouds on the north changed my original plan to Skyline, so my kids and I drove to Anderson Lake in Morgan Hill to stay away the clouds. My decision was paid off, the sky was crystal clear except very few clouds on the lower western sky.
Using crescent moon as the reference it was easy to locate the comet. I first spotted it at 19:50 in my 8×50 binoculars, 4 degrees left to the moon. It had a moderate bright core with a very tiny, light, fan shaped tail (due to bright background). The best view was between 19:55 and 20:00. The bright core looked like a water-drop (or upside down ice cream core), I think the core itself was near round, the “triangle” was brightest part of the tail. The long, narrowed fan shaped tail stretched about 1/2 of moon diameter (direct vision), or 3/4 of moon diameter (avert vision), at PA of 20 degrees. Both core and tail were white. With naked eye, it was barely visible, no tail could be seen.


Comet Panstarrs (C/2011 L4) and Moon
03/12/2013 19h48m

Comet Panstarrs and Moon: 1s at ISO400. 70-200mm zoom lens at 70mm. Cropped and enhanced for contrast.  The comet was ~4 degrees due left to the crescent (1 day old) moon. The scene was breathtaking even without comet – the hair thin crescent moon hanging low over the crystal clear, colorful sunset sky.


Comet Panstarrs (C/2011 L4) and Moon
03/12/2013 19h59m

Comet Panstarrs and Moon: 15s at ISO400. 70-200mm zoom lens at 200mm. Cropped and enhanced for contrast. This resembled what was visible through my 8×50 binoculars – very bright core with fail tail.


Comet Panstarrs (C/2011 L4) and Moon
03/12/2013 20h00m

Comet Panstarrs and Moon: 30s at ISO400. 70-200mm zoom lens at 200mm. Cropped and enhanced for contrast.


Comet Panstarrs (C/2011 L4)
03/12/2013 20h00m

Comet Panstarrs: cropped from the above image and then enhanced for contrast. 30s at ISO 400. The core was very bright and elongated, with ~30′ fan shaped tail.


The sky did not look promising at sunset, when the Cirrus clouds hang over the western and northern sky. Regardless I setup my camera at bayland park trail again. The clouds over the coastal range dispersed and the sky was almost completely clear. I was able to spot the comet with binoculars at 17:52PM, since I did not bring my tripod mount for binoculars, I spent rest time taking some pictures.


Comet Panstarrs (C/2011 L4) and Moon
03/13/2013 20h02m

Cropped and enhanced for contrast.


Comet Panstarrs (C/2011 L4) and Moon
03/13/2013 20h12m

Cropped and enhance for contrast. Crescent Moon and comet over silicon valley evening sky.


Comet Panstarrs (C/2011 L4)
03/13/2013 20h07m


The sky did not look so good when I left home, the high and mid clouds were pushed from North and the lower N and W horizon was covered with some clouds. I decided to go to Anderson Lake in Morgan Hill again to avoid the clouds, without knowing what the condition would be, because there was my last chance before the full Moon. It looked like I would be washed out when I arrived there, but I was a little bit lucky again – the clouds dispersed quite a bit when night fell though they still persisted above the horizon. Finding the comet was not an easy task since I switched to my telescope and to my non-goto mount. I had to use my binocular to find the closest bright star (DeltaAND).  I finally spot it with my naked eyes which made finding the comet breeze. I took some pictures with my AT72ED, I did not have a lots of time so the result did not match my expectation, partially due to the haze and passing clouds.

Picture saved with settings applied.

Comet Panstarrs (C2011/L4)
03/24/2013 20h28m

This is a stack of 9x5s photos taken with T3i through AT72ED, processed with DeepSkyStracker. ISO1600. It clearly shows the bright core and ~15′ fan shaped tail.

Picture saved with settings applied.

Comet Panstarrs (C2011/L4)
03/24/2013 20h25m

This is a stack of 10×2.5 photos, ISO1600, processed with DeepSkyStacker.


Went out in the evening to capture Panstarrs and Andromeda. Most late afternoon high clouds disappeared when sun set, but haze and lingering clouds still covered N and W horizon, together with lights from nearby baseball field, made only the brightest part of comet and galaxy visible.


Comet Panstarrs (C2011/L4) and Galaxy Andromeda
18x15s ISO 800

This is a stack of 18x15s, ISO 800, Nikon 70-200mm lens at 70mm. Stack with DSS, processed with FitsWork.


Comet Panstarrs is moving North and has become a morning comet, since the viewing condition is much better than the evening. On 3AM morning I headed out to Windyhill Open Space parking lot on Skyline Blvd,  the sky was  crystal clear, no annoying haze or high clouds, except light dome from Silicon Valley towards North and East.

I took lots of close up photos with my AT72ED on CGEM mount, as well as wide angle photos with 70-200mm zoom lens, to show the comet and Galaxy Andromeda.


Comet Panstarrs (C2011/L4)
30s x 46, ISO 1600


Comet Panstarrs (C2011/L4)
60s x 5, ISO1600

I believe that I was able to see the comet with my naked eye without much difficulty, it looked  like a small and dim star but with fluffy feel  (I could also feel that it was not a “point” ). With my 8x50mm binoculars, the comet had a star like nucleus which was about 7m magnitude. The nucleus was surrounded by mist coma which shows almost no condensation. Nucleus and Coma were much fainter than when the comet was first appeared in the evening sky a month early. The tail was straight, looked similar to Coma – dim, mist and no condensation, it was about 20″ long, pointing 30 above the horizon.

4/17/2013 (Aloha from Maui)

I went to Maui for vacation with my family during spring beak. I did not particularly planned for any star gazing activity until I learned that Panstarr is hosted on Halealkala Observer story which is on summit of Haleakala NP. I suddenly realized that I might be able to visit on of the darkest sites on earth for star gazing. I contacted Becky Sydney, the president of Maui Astronomy Club, expressed my desire to have  star gazing at Maui, and the summit. She provided detailed and  useful information on how to observe sky on island, she also introduced me to Rob Ratkowski – president of Haleakala Amateur Astronemer which owns a observing site on the summit.I communicated with Rob via email and also met him in person during our stay. He lent me his equatorial tracking mount so that I could take some pictures with my DSLR.

On the very next day after arriving Maui, my family drove up to Haleakala National Park for sightseeing. I could not believe that we were 10000 feet above the sea level in merely 38 miles drive. Overlook of volcanos from several lookout areas was stunning and unforgettable. When I arrived parking lot on the  summit I saw 4 big domes, shining under blue sky and white clouds.

The weather in next few days was not good at all, cloudy and even rainy on some days, and I did not even get a chance to watch beautiful Hawaiian beach sunset.

On April 17th, the sky turned clear but it was very windy. I did not plan to go to the summit initially, but after considering the weather forecast (not as accurate though) and moon set time, I rushed out with my old son to the summit.

I arrived at the summit at 1AM, just after moon set. The sky was crystal clear and dark, it was the first time that Milky Way looked so bright.  But it was cold and windy, I felt chilly even with my sweater on. I spent about 20 min to observe a few eye candies – Omega Cen, Alpha Cen, Bet Cen, Southern Cross and Milky Way.

I was planning to take some close up as well as wide angle images of various objects. But it was so windy that the tripod was too shaky to use big lens, so I gave up close up imaging after failed a few times.


Milky Way on Haleakala Observatory
Canon T3i, 18mm, ISO 1600, 8x1min

After finishing up above pictures, I just realized that it was time to take some pictures of comet Panstarrs. A quick check show that it was rising behind the domes. It did not take me too much time to decide what to shot – Panstars over Panstarr dome (I am not sure whether the dome hosts Panstarr or not, any how it is still a rare opportunity to take comet Panstarrs at Haleakala Observatory site).


Comet Panstarrs over Panstar
Canon T3i, 35mm, ISO 1600, 60s, tracking mount


Comet Panstarrs over Panstarrs Dome
Canon T3i, 50mm, ISO 1600, 60s x 5, tracking mount


Comet Panstarrs over Panstarrs Dome
Canon T3i, 50mm, ISO 1600, 60s x 5, tracking mount

With my 8×50 binoculars, a 7m stellar nucleus  (simiar to HD1598) was surrounded by a mist of thin clouds with no condensation, and avert vision detected  a 30′ tail (15-20′ with direct vision) pointing to HD1598. The tail was thin (density), with no condensation (which looked same as the mist cloud surrounding the nucleus) for most part of it, and gradually faded  for the rest.


I took the advantage of clear sky and marine layer  which reduced the sky glow from the valley, at Windy Hill OSP parking lot on Skyline Blvd. The sky was clear with excellent seeing, weather was dry and warm since it was above the marine layer. Wind was calm. I took picture of Panstarrs and Lemmon.


Comet Panstarrs

40 x 60″, ISO1600, AT72ED on CGEM


I took this picture on E Dune Road to Henry Coe, the sky was great and there was not much light solution there. Two tails were visible in the picture, one bright straight tail, and another fail one on the opposite side.


Comet Panstarrs

20 x 90″, ISO1600, AT72ED on CGEM


Again I took the picture of Panstarrs on E Dune Road to Henry Coe. This time I was shocked by its long, straight and bright tail, it became much stronger than last time; and there was aslo fan shaped faint tail on the opposite side.


Comet Panstarrs

61 x 105″, ISO1600, AT72ED on CGEM

2012/06/05 Transit of Venus Photo Gallery

This post includes some photos taken during the transit, click here to see the details of the transit viewing event.

My Kids

My kids in front of the telescopes, taken at 14h17m, before the transit began.

Composite Transit of Venus Ingress Photo
ISO100, 1/500s

This composite photo contains 15 cropped photos  (100% zoom, un-processed) taken between the 1st and 2nd contact.

The first 5 photos show detailed progress of 1st contact. The Venus is already visible in the 1st picture (a tiny dent on edge of the Sun), which was taken just 16s after predicted time. The 2nd picture was taken 3s after I had noticed the Venus visually using liveview of T3i camera.  In the picture taken at 15h23m29s and 15h23m50s, blackdrop effect is clearly visible.

The Venus in most of these photos is blurry due to wind and seeing.

15h15m00s, ISO100, 1/500s
Mid Ingress

This photo was take at 15h15m00s, when Venus was about half way through the ingress.

16h50m00s, ISO100, 1/500s
Venus Transit

This photo was taken at 16h50m00s and it was the sharpest photos for the transit.

Transit of Venus Composite Photo
ISO100, 1/500s

Stack of 9 photos (100% zoom, un-processed) taken at: 15h20m00s, 15h49m00s, 16h19m59s, 16h50m00s, 17h20m00s, 17h50m00s, 18h20m00s, 18h50m00s, 19h19m59s. Note: The it is rotated 90 deg counter clockwise after stack.


Sunset at 20h13m, when transit was still in progress.


This was the setup I used for the transit (except for the camera which was being used to take this picture):

– Celestron CGEM
– AT111 EDT (white), F/7, full aperture Baader AstroSolar visual filter
– AT72ED (black), F/6, 2″ diagonal, 9mm Nagler T6 EP.

2012/06/05 Transit of Venus

This is the first (and also the last) Venus transit experience in my life (I don’t expect that I will still be alive 105 years later).

Transit of Venus Composite Photo
More photos are listed in transit photo gallery

Since most part of transit (1st/2nd contact and mid-transit) would be visible, I decided not to travel unless the weather became an issue.

The forecast did look good on the transit day – scattered mid clouds in the morning and clear sky in the afternoon. It was not the best – it was clear (without even a trace of the cloud) with excellent transparency and seeing for the next few days ; it was not the worst either – it was rainy and windy the day before (very unusual at this time of the year).

At 12PM, scattered passing Cumulus clouds still covered 30-40% of the sky and it did not look to be clear soon. I decided to drove up to the site near the coast (on the west), because the satellite image showed that the sky near the coast was clear so it would unlikely be clouded out during the 1st/2nd contact. The sky got completely cleared up (almost cloudless) at 1:45PM so the decision was not bad. But probably I should have gone to Henry Coe (on the east), where the sky became mostly clear at 3PM, and remained in very good condition after mid-transit when the clouds moved into the coast. But I did not want to take chance, being clouded out during the 1st/2nd contact would ruin the entire viewing experience.

I set up the telescopes on a pullout on HW35, near the junction with HW92. The pullout was on the mountain ridge overlooking the Pacific Ocean to the west . Usually it is breezy at the coast ridge. It was no different on the transit day (~15m/h), and it did not seem particularly worse than other places since the forecast was breezy for the entire valley.

Viewing Site

My kids and I spent a few minutes to view the sunspot to figure out the 1st contact position. It did not take much time, thanks to the composite photo (sun image + predicted transit path) posted on

My Younger Kid Was Viewing Sunspots Before The Transit
CGEM mount, AT111EDT (white) for imaging, AT72ED (black) for visual with 9mm Nagler T6 EP

At 3h06m, my older kid and I started to look for the venus. My kid observed visually using AT72, and I used Canon T3i on AT111 (liveview). At 3h07m03s, by coincidence, we both noticed a small bump/dent on the edge of sun at the predicted position. The dent got bigger and bigger and soon 1/3 of the venus became visible.

There were two special phenomena we were planning to look for – aureole and black drop.
All I knew about the transit was black drop, until I learned aureola from the article in Sky & Telescope two weeks before the transit.

When the venus was half way entered the sun, my son claimed that he could sense the entire disk of the venus. He had shaper vision but I doubted whether it was just an illusion.

At 3h16m, we noticed a bright, thick, light orange arc (spanning ~45 deg, starting from the left point where Venus and Sun intersected) through AT72. My son also noticed the much smaller, dimmer arc on right side intersection point. At 3h19m, ~3/4 of Venus moved into the sun, the aureole – “ring of limb” – appeared. It was hair thin in the middle and slightly thicker (~2x thicker) near both intersection points. It was light orange too but much fainter than the “arc”, and was easy to miss. My son told me later that the ring was broken at 2-3 places in the middle. I did not notice it and I am wondering if it is “baily bead” of transit.

Around 3h24m00s, right after predicted 2nd contact, my son exclaimed that the black drop had started. Initially it was wider and darker, then gradually became narrower and lighter as Venus was moving away front the edge of the Sun. On 3h2420s, the black drop was gone visually and venus moved completely inside the sun. 2-3s prior to it the black drop because a thin line, so my son was able to tell the black drop was about to finish.

I took a few pictures of black drop. Though not as clear as I hoped due to the wind, it did seem that the black drop was not as prominent as visual observation, probably due to a better optics.

After 2nd contact, the venus crept over the sun. It became so boring that my kids stayed in the car playing the game. I took the picture every 5 minutes.The sky remained clear with average seeing until 6:15m. Then high clouds moved in, the seeing became so poor that sun and venus looked like were swimming in the ocean. I could see the turbulence in 9×50 finderscope, which was barely noticeable in AT72ED during the first half of the transit.

At 7h30m, more high clouds moved in and seeing remained very poor so I decided to give up.

It was a truly unforgettable experience. We felt so lucky that we not only experienced the once-in-a-lifetime event, but also witnessed both rare phenomena.

The biggest lesson I learned was that I should have used the fastest shutter speed to take the transit photos. I used 1/500s for all my photos and most of them show blurred venus due to wind and seeing. It would have been much better if I had used 1/1000s or faster.

2012/06/04 Partial Lunar Eclipse

Composite of 8 photos taken between 2:45AM ~ 4:30AM, shows the progress of the eclipse.

The forecast did not look promising, the clouds would move in at 3AM, right in time to ruin the eclipse. Henry Coe State Park, my usual viewing place for special astronomical event, would have better sky. But since it was partial eclipse and the transit of venus was coming on the next day, I decided to view it from my home only.

I woke up at 2AM, the sky was crystal clear without even a trace of cloud, everything was bathed in the moonlight. It seemed that the it would remain in this condition forever, however the satellite image showed that the clouds were on their way.

Regardless I grabbed my AT72ED refractor and CG3 mount, with T3i camera. I set them up on the sidewalk outside my house, where the moon would be visible throughout the eclipse thought the gap between the trees.

I focused the camera and started taking photos at 2:40AM. The shadow of earth was already visible at 2:50AM, long before the eclipse began.

02h49m13, 1/320s @ ISO100

Taken at 02h49m13, about 10 min before the 1st contact. The penumbra of earth shadow was already visible.

The first high clouds showed up at 3PM, coincided with the first contact. The thin clouds did not interfere eclipse viewing until 3:20AM, when broken mid/low clouds started rolling in. The moon was still visible through the clouds, but I could only take some good photos when moon appeared in the opening in the clouds from time to time.

03h00m03s, 1/320s @ISO100
First Contact

The first contact, taken at 03h00m03s, part of moon had already been covered by earth shadow.

At 3:40AM, I noticed earthshine of the eclipsed moon by naked eyes when the sky was clear. I was a little bit surprised because usually earthshine is visible when moon is less than 5 days old, and this was the first time I saw it during eclipse (partial and total).

03h40m05s,  0.2s @ ISO100

Taken at 03h40m05s. The earth shadow was visible in the photo and it resembled what I saw with my naked eyes. You may also notice the transition area between umbra (almost full dark) and  penumbra (full bright).

03h41m53s, 1.0s @ ISO100

Taken at 03h41m53s, the rusty red color was visible in the earth shadow.

The sky condition continued to degrade. At 4:00AM the moon barely appeared behind the clouds; at 4:30AM, a low cloud bank moved in from the west and it completely blocked the moon, so I wrapped up my equipments and returned home.

Greatest Eclipse

Greatest eclipse, taken at 04h03m48s.

The time of each contact:

Partial Eclipse Begins: 02:59:53 PDT
Greatest Eclipse: 04:03:13 PDT
Partial Eclipse Ends: 05:06:30 PDT

Location: Sunnyvale, CA
– AT72ED
– CG3 mount with RA motor
– Canon T3i

2012/05/20 Annular Eclipse Photo Gallery

This post includes some photos taken during the annular eclipse, click here to see the details of the eclipse viewing event.

This photo combines 15 photos taken at various phases of the annular eclipse, shows the shadow of the moon creeping in front of the sun from the West (bottom) to the East (top). Click here for the full size photo.

Annular, from 2nd to 3rd contact.
ISO100, 1/800s

Annular phase: 9-photo composite, click here for the full size photo.

17h16m54s, 1/500s @ ISO 100 
First bite, 6 sunspot groups also marked.

18h28m52s, 1/800s @ ISO 100
2nd contact

18h31m03s, 1/800s @ ISO 100
Greatest eclipse

You may notice that the “ring of fire” was a little bit off towards the North (right) because the my site was a few miles south of predicted center line.

18h33m15s, 1/800s @ ISO 100
3rd contact

18h17m43s, 1/800s @ ISO 100
Solar Eclipse

The moon was about to cover sunspot 1486.

19h32m06s, 1/640s @ ISO 100
Approaching 4th contact

Sun was low in the west horizon and partially blocked by the clouds. Taken at 19h32m06s.

Arguably, the most dramatic view of annular eclipse is bailey bead, though not as splendid as diamond rings of total eclipse. This was my first annular eclipse observation and I failed to capture the most beautiful bailey beads (I should have taken more pictures near 2nd and 3rd contact, probably 1s apart for 10s). Nevertheless I got some nice shots.

The followings are 3 composites of bailey beads, each contains 3 pictures taken ~1/4s apart. You can see that there was noticeable change in the appearance of bailey beads even in this very short period of time, esp in 2 3rd contact composites.




Though not as spectacular as bailey beads, it was still thrill to watch the sunspots disappearing behind and appearing from the shadow. The following two pictures – each with 4 photos stacked – show the occultation of sunspot AR1484.

SolarEclipse_20120520_Sunspot_Ingress SolarEclipse_20120520_Sunsport_Egress

I also created a time lapse video, which can be accessed here. It shows eclipse progress every minute.


My Kid and My Equipments

– Celestron CGEM
– AT111 EDT, F/7 (White)
– Full aperture Baader AstroSolar visual filter
– AT72 ED F/6 (Black)
– Canon T3i

2012/05/20 Annular Eclipse


2012/05/20 Annular Solar Eclipse Composite

This is my first annular eclipse experience. Though the annular would not be as stunning as the total, I decided to set out another eclipse expedition (my first was 2009 total eclipse in China), as the next annular opportunity will probably be 20 years later.

About a month prior to the eclipse, I did some search on possible sites along the center line. Some people preferred the beauty of baily’s bead, but I would stay on the center line to enjoy the perfect “ring of fire”.

This was the first time I used Google Earth. In addition to Street View, Google Earth could also show the Sun’s position in the sky at any given time. Both were used to determine whether the western horizon would be clear from trees, buildings or mountains during entire eclipse.

I selected about 6 sites, from Redding, CA to the Fallon, NV, through Nixon (Pyramid Lake area), hoping to get at least one or two sites which would be clear on the eclipse day. My most favorite site was Shasta Dam where I had visited less than a year ago. It was easy to access, and had a nice lawn near the visitor center where the telescope could be set up. But the weather did not corporate, the forecast showed that the high cloud of a cold front would move in N. CA on Sun afternoon, possibly ruined the eclipse viewing.

So my choice would be somewhere in NV. I arrived at Cason City, NV on Sat night with my kids. On Sun morning, I checked local weather forecast, NOAA Reno favored Reno, Pyramid Lake and Central West NV area. I was not too sure about Reno, because it was too close to Sierra Nevada so the weather could change any time. Further more both SkippySky and CSC indicated that the region north of Pyramid Lake, and south of Fallon would have some clouds. I decided to drive to Fallon to stay away from the mountain ridges, meantime I would still have time to drive around (either to the Nixon on the N, or to HW121@HW50 on the S) based on the local weather. On my way to Fallon, there were some annoying high clouds to the North (presumably over Pyramid Lake), so I headed directly  to Grimes Point, which was a few miles southwest of Stillwater Reservoir which was on the center line.

Viewing Site

While waiting for the eclipse, we took a short (~1/2 mile) hike to the ancient Indian petroglyph site. The site was relatively small and most petroglyph have been weathered, but it was interesting to see it as a side trip.

Indian Petroglyph

My kids at Hidden Cave

The scattered clouds to the West and South started to develop at 2PM, hanging over the mountains. I paid my attention particularly to the South, because both CrippySky and CSC forecasted mid clouds, though CrippySky was a little bit optimistic. For the next two hours (actually till the end of eclipse), all the clouds were confined over the mountains but developed quite a bit, esp the one to the south, which merged to a big bank and covered the entire mountain ridge there.

Fallon’s weather was not always promising. I had been checking the satellite image for about a week poor to the eclipse day, and noticed that the clouds developed in the afternoon over the maintains to the east, and moved either further to the east (great), or to the west (bad) and covered Fallon and Reno, depending on the wind.

The weather on the eclipse was proved to be perfect for such expedition. The sky was crystal clear, and the high clouds near horizon did not interfere the eclipse except for last 10 minutes. The seeing was great, details of the sun spot and brighten area near the limb were easily visible.

To my surprise, there were only about 20 people showed up in the parking lot, one with a short tube refractor telescope and camera, 2 or 3 of them with tripod and camera, rest with eclipse glasses, I was wondering how it would be different for them to view the eclipse here than at their home. Almost all the people seemed to be impressed by my setup.

My Kid and My Setup
CGEM mount, AT111EDT (white) for imaging, AT72ED (black) for visual with 24mm Panoptic EP

It was hot and breezy when the eclipse started. But as the eclipse progressed (~30 mins), the wind subsidized and the temperature became cooler, and the conditions remained comfortable until the end of the eclipse. However I had a hard time to view the laptop screen due to sun light, next time I would need to bring something to block the sunlight.

As time went by, the moon crept over the sun, and the crescent sun looked more like a moon. You would not notice moon’s moving at all at first, but as the 2nd contact approached, the crescent sun seemed to look different every second. Finally the moon completely moved inside the sun and the fire of ring was hanging in the western sky – a beautiful scene that one would never forget. It was so beautiful that everyone seemed very excited. The annular eclipse lasted about 5min, after which people started trickling away.

Maximum Eclipse
More photos are listed in annular eclipse photo gallery

When the moon finally moved out, it was almost 19h40m. The sun was low in the western sky and blocked partially by the clouds over the mountains.

On 8:15pm, the final part of the expedition began – 5-hour drive back to the home. It was a tough drive, after 3-hours tireless observation under the schoching sun.

Overall the expedition was a great success, after a month planning and preparation.

The most difficult part of the eclipse planning has always been how to beat (not really) the weather .It is always a tough decision when the forecast is not perfect. I use the following information available to make the final decision:
– Aviation forecast: most accurate but only for 24-hours, and should always be checked first if there is an airport nearby
– CSC and SkippySky: it is hard to tell which one is more accurate, so I check both to see if they agree with each other
– Satellite image