Saturday, September 10, 2011

NUS Rooftop Observatory

Sorry for not being able to blog as much as I would like to for the past couple of months. Way too busy with real life and enjoying myself under clear skies and meeting fabulous fellow amateur astronomers. I think I have enough material to blog until the rest of the year - snatching great astro bargains, well-received sidewalk sessions, checking out new potential observation spots in Singapore, solo train adventures to Malaysia, catching meteor showers at Changi Beach, week-long observations under stunning Milky Way skies in northern Johor, visiting the Observatory at the Science centre for the first time, meeting Dr Fred Watson, observing through a large dobsonian telescope under Sedili skies ...etc. So stay tuned!!

Coming back to topic, you may wonder what made me so motivated to update my blog now? How about seeing fully grown adults who are experienced visual amateur astronomers who owns some decent telescopes behaving like kids in a candy store?

A couple of weeks ago, my astro buddy James asked me if I am interested to attend a private first light party at the spanking new rooftop observatory at National University of Singapore (NUS) equiped with a brand new 17-inch telescope. He had me at NUS rooftop observatory! Brand new 17 incher? Wow. I don't care if William and Kate will be visiting me that night but there is no way I am going to miss such a rare opportunity. YESSS! PLLLLEASE!

James contacted the event organiser who was gracious to extend the invitation to me and a couple more of James's friends. The event organiser was Prof Chan. Just a quick note about Prof Chan. There are some professors who have airs. But not Prof Chan. I remember clearly our first encounter. We were going to Punggai (Johor, Malaysia) for a weekend stargazing trip last year together with a big group of students. The meet-up place was at NUS. I took a cab there since I was lugging a 8-inch telescope, a telescope mount and tripod and a bag stuffed with clothings and astro accessories. When I arrived, I stepped out of the cab and was slowly unloading my stuff on the ground when I saw someone rushing towards me from a tour bus some distance away. Yupe, that's Prof Chan. He helped me carried some of my stuff to the bus. I have another astro buddy who stays near my place who was a student of Prof Chan and also had many nice things to say about him.

The first light star party for the new observatory was conducted on Wednesday 17th August 2011.

On that evening, I was happy that Gavin, another astro buddy of mine, will be attending the event too. More about Gavin when I blog about our recent Persied Meteor shower overnight trip at Changi Beach (Chinese Hungry Ghost Month to add :)). Gavin and myself joked that there will a huge cyclone hitting NUS soon. There is a well known phenonmenon/joke in the astro circle that whenever the someone buys a brand new telescope and try to use it for the very first time (aka first light), bad weather will befall upon that poor soul. The intensity of the bad weather will be proportionate to the size of the primary mirror or lens (aka aperture) of the new telescope. Imagine a 17-incher.

I met up with Carole while waiting for James to pick us up and drive us to NUS. Carole is well known for organising numerous stargazing trips to Malaysia over many years. Check out her blog and email her if you or your organisation/school is interested to stargaze there. It was nice to catch up with Carole again since our last trip to Desaru Damai Beach Resort (Johor, Malaysia) with a group of educators and students. Upon my enquiry, she was very generous to share with me some great advice about custom clearance of stargazing equipment base on her many years of encounters with custom officers.

James arrived as the sky turned dark and miraculously, the sky was clear! We were all very excited on our way to the new observatory. When we arrived at the carpark, we met Alfred. I am glad to finally meet him in person for the first time. I have heard many wonderful reviews of his solar astro gear and hopefully can spend some quality observing time with him and James in our next trip to Malaysia.

We took a lift halfway up the building and took the stairs for the remaining half. On our way up the stairs, I saw Prof Chan and the invited guests having dinner in a room. As usual, the ever-cordial Prof Chan invited us to have our dinner. As I already had my early dinner around 5 pm (masala thosai at Jurong East foodcourt), after saying a quick hello to him, I proceeded quickly upstairs to the roof to check out the star attraction. Only a few more steps on the stairway to astro heaven!

Upon reaching the rooftop, I saw the flat retractable observatory rooftop design instead of the typical dome. Excited murmurings could be heard streaming out from the observatory. 

Took off my shoes and stepped into the candy shop. Drumroll please ......

You can watch the high definition version here.

The bright red star shown in the video is Antares in the constellation of Scorpius.

For the astrophotography pros out there, sorry for the poor quality and out of focus star trails in the astrophoto in the video. I was using my 4-year old point-and-shoot compact camera on a small fexible tripod. As it was quite crowded in the room, it was quite a challenge to do long exposure photography without someone walking in front of the camera. More importantly, my main focus was to observe through the scopes and not to waste too much precious observing time on photography and videography.

The main telescope is a PlaneWave Instruments CDK 17 ( Mounted on it is a Takahashi TSA 102 (

I took my first look through 17-incher when it was pointed at the globular cluster known as Omega Cenaturi. The object was off center in the eyepiece but still I could see the parts of it which was fully resolved into small little stars.

The next object was Saturn. Contrast and detail wise, it was not the best I have seen so far. But this is a totally unfair comparison. My best view of Saturn was when it was closer to earth, observed at almost zenith position, in very rare clear skies in Singapore. But Saturn that night at NUS was quite low at about 25 degrees above the horizon, was way pass its opposition in April this year and the seeing of the sky was just average.

I suspect the telescope collimation was a little bit off. But the good thing about this design is that one can easily collimate the telescope by just turning the 4 collimation knobs which are located within easy reach in the front. Unlike a typical Newtonian telescope, one has to collimate both the primary and the secondary mirror. Detail official collimation instructions for this telescope in pdf can be found here.

In terms of brightness, Saturn was very bright through the telescope and its brighter moons shining like little stars, thanks to it big aperture primary mirror collecting lots of light. This brightness is hard to beat in a typical non-observatory class telescope. That Saturn view gave us a tantalising preview of its true capabilities under better viewing conditions. In the next few years, Saturns ring will open up wider and wider. The Lord of the Rings will definitely put up one good show after another for this and many other telescopes in the world.

Jupiter opposition will occur on 29th October 2011, just two more months to go. The next time it will be that near to Earth will be in 2022. Lucky are NUS students and lecturers who have access to this observatory during that period. I hope by that time, they have already observed Jupiter through smaller telescopes. Then, they will truly appreciate what they see in this monster telescope and realise how fortunate they are to have access to such an observatory in their own school.

Next, we saw the NGC6231 star cluster. A nice tight group of stars against a dark sky. The Tak 102 refractor gave a nice wide field of view of this object with pinpoint sharp stars. The longer focal length CDK17 showed a higher magnified view with a darker background sky.

As we did not have access to a 90 degree diagonal at that time, we were looking straight through the telescopes and finders. For objects higher up in the sky, it will create some discomfort in the neck while viewing. But looking at the bright side (pun intended), without an additional mirror or prism that will be added to the light path by a diagonal, the views were as bright as they can be. The step ladder in the observatory did offer some relief as we could use it a observing chair and sit on it or hold on to it to balance ourselves while looking up.

We then saw the double double in the constellation of Lyra. Needless to say, the four stars split very nicely.

It was fun to see and hear these telescopes slewing from one object to another. The slewing noise (music to astronomers?) was surprisingly low for such a huge setup. I guess it's a geek thing. I remember during one of the private star party I had attended, someone told me other than seeing the green laser in action for the first time, seeing an big telescope slewing automatically for the first time is almost more fun than seeing the objects through it.

The telescopes were remotely controlled via TheSky planetarium program via a Showa ATLASTAR Telescope Controller. The big red emergency button looks really cool.

With the camera safety strap around my wrist, I find myself holding the camera just a little bit tighter when I tried to take a shot of the primary mirror from the front. It will not be a very good idea to accidentally drop my camera right into the telescope and spoil my mean the mirror. :)

Later in the evening, I asked if I could try to focus and move the telescope using the hand controllers. The students in-charge were kind enough to give me the go ahead. The hand controller unit that moves the telescope has a nice magnetic back that allows one to easily stick and remove it anywhere on the main metal pillar. Very nice touch. This prevents it from accidentally dropping on the floor or its wire getting entangled with other wires. There are four buttons that control the direction of movement and adjustable knob that controls the movement speed. The movement was very smooth with no perceivable backlash (delay from moment of pressing the button to actual movement). The up and down buttons on the hand controller held near to the base of the telescope controls the focusing of the telescope.

Pressing a button and making something move doesn't sound like big deal. But for me, that was really exciting. Because this telescope setup is the most expensive and exquiste piece of machinery I have ever controlled in my life. Moreover, the excitement was enhanced by the anticipation of the view of the object moving into the field of view as it may be the best view of that object I have seen so far. Afterall, I have not looked through a telescope bigger than a 17 inch at that point in time.

The magnificent and bright globular cluster know as M22 is a fantastic object to look at. In average seeing skies in Singapore through a 8" reflector telescope, one could most probably just see a fuzzy cotton ball like object. Through this CDK17, using a 14mm Televue Radian eyepiece, M22 was clearly resolved into a ball of individual bright stars! My best view of M22 so far!

A couple of hours into the evening since we started observing, the Ring Nebula (M57) seems to be a good target as it rose higher up into the sky. This object looks like faint fuzzy Polo sweet in my 8 inch telescope under average seeing Singapore skies. When the telescope stopped slewing toward this object, I looked through the Televue Nagler 7mm eyepiece and pressed the buttons on the controller, trying to manoeuvre this object into view. With this eyepiece, the magnification is a high 420x and very small field of view of only 6 arc minutes. I have never tried looking at this object with such a high magnfication, let alone on such a big telescope.

Suddenly, I saw a bright half halo at the edge of the view and immediately release my pressure on the button. I must be moving in the wrong direction. But wait. That was puzzling. This is a premium eyepiece on a well-baffled big telescope. I should not be seeing such bright light scatterings. Moreover, there isn't a very bright star very near to the Ring Nebula. Also, the reason could not be that the automatic mechanical slewing accuracy is that way off. This is because, the view in the Tak 102 (which is aligned with the CDK17) is pointing directly at the location of the object, right between the 2 bright stars in Lyra.

I pressed my thumb on the same button to continue swinging the bright half halo to the center of the view.

Then the bright "half halo" became a ring. *THE* Ring. I yelled, "I've found it!!".

That was the most beautiful Ring Nebula I ever saw. Big, bright, high contrast, direct vision. The details in the smoky ring structures were something I have not seen before. Wow. During those precious seconds I was observing it, I totally forgotten I was observing under Singapore skies. Those who were still around in the observatory took their turn to enjoy this beautiful deep sky object. After James and Gavin saw it, I could tell from their expressions and comments that they were equally amazed, if not more.

Later, Gavin had a idea to do a Edwin Hubble pose (see photo below) beside the CDK17.

Credit: California Institute of Technology archives
After a few tries, this is my best shot with some photoshop post editing.

We should bring a smoking pipe next time for a better effect.

If NUS physics department needs to raise funds, they can consider charging $20 for such photo taking sessions. :)

Throughout the evening, though there was a slight haze blanketing the sky, not one single cloud blocked our view of the sky. But all good things must come to an end. The hosts were already very generous by extending the "partying" time way beyond the official closing time at 9.15 pm. I joked with Gavin earlier in the evening that we should hide in some restroom and then secretly crawl back into the observatory to continue our observation when everyone has left after midnight.  We left at about 10 pm and the clear sky was still holding up. In fact, even when James reached home, the sky was still clear enough for him to observe the Ring Nebula with his 8 inch telescope while his memory of the view in the CDK17 was still fresh. No points for guessing which scope had the much better view.

Big observatory-class telescope like this CDK17 is financially out of reach for the majority of amateur astronomers in the world, including me of course. To be able to touch it, control it and see through it , even for just a couple of hours under decent night skies, is truly a great privilege and blessing. I would like to express my heartfelt thanks to Prof Chan and James for the invitation and all the event organisers, students and helpers for making the first light party a great success.

I wish the NUS Physics Department all the best in making full use of the observatory and producing great physicists for many generations to come!