In the Philippines, the rainy season usually starts in the month of June and runs through about November. During this period, thunderstorms and typhoons which generally affect a wide area (sometimes half of the archipelago) are common. In fact, only this June three typhoons (namely Dodong, Egay and Falcon) have already visited the country along with heavy rains.
Clear skies were seldom visible for most of the month of June was so stormy. Hence, having an opportunity to spot this season’s prominent constellations during clear nights was really a blessing to an amateur astronomer like me. 🙂
The sky was moonless on the first week of June. So I took this chance to set up the tripod and the Panasonic Lumix digital camera to get nice constellations images. Thanks to Aaron Misayah for loaning his camera to me. 🙂
The Lumix camera features a ‘starry night’ scene mode — a setting which allows you to capture long exposures, with 15, 30, and 60 second shutter speed options. I selected the 60 sec exposure and point to regions of some of my favorite constellations.
Note that the Lumix didn’t have ISO control when in starry night mode. If I set the camera to manual mode (where I do have access to the ISO settings), I don’t have access to the exposure time. The longest exposure time I have in manual mode is 1/8 seconds. But after I looked at the pictures in manual mode (ISO 1600, 1/8 seconds exposure), I notice that there are a lot of noise. I think they’re trying to hide the fact that the Lumix is very noisy in high ISO mode so they made it not selectable when you’re using long exposures.
Anyway, below are some of the photos I took from our residential area in San Jose del Monte, Bulacan. I used Photoshop to add the constellation lines.
1 June 2011
camera settings: 6mm, f/2.8, 60 sec. exposure time, ISO-80
Zooming into the photo above will reveal vertical streaks (not the star trails). These unnecessary streaks have occurred because I forgot to use the self timer on the camera for this shot. By clicking on the shutter button, even a slight vibration from the finger would create blur on the picture, even when you are using a tripod.
5 June 2011
camera settings: 6mm, f/2.8, 60 sec. exposure time, ISO-80
By the way, I am living from a suburban site. The limiting magnitude for such a location is frequently close to 4 . This means that the apparent magnitude of the faintest star that could be visible to the unaided eye is about magnitude 4.
The original images were a bit darker but I increased the brightness and contrast in the post processing to find out the dimmest star recorded. I found that every star that was visible with the naked eye was in the image, which is good! The results of each shot have actually far exceeded my expectations. I never thought that a little humble compact camera could go a long way.
I have also tried using this camera in shooting landscape and scenery pictures and it also produced good results. Click here to see my previous post about it. At about 30-45 minutes after the sunset, the sky is not completely dark yet, but the colour appears to be more intense with traces of natural light still available. It would also be nice to take sky photos during this time.
Perhaps, this could be an interesting camera at a truly dark sky site. I have yet to try that when I still have the opportunity. 🙂
Despite the 50% predicted cloud cover and significantly large uncertainty in the precise time of the peak, I and some of my orgmates in UP AstroSoc tried our luck in observing the first meteor shower of the year during the night of January 3 until the dawn of January 4, 2011. According to British meteor astronomer Alastair McBeath, the narrow peak of this shower is predicted to occur some time between 2100 UT on 3 January (5AM on January 4) and 0600 (UT) on 4 January 2011 (2PM on January 4), however the radiant of the shower is very low in the evening hours, and will rise higher towards dawn so the best time to view this event in the Philippines was during the predawn hours of January 4.
This was my first time to observe the Quadrantid Meteor Shower. Unlike the other popular annual meteor showers like the Perseids, Leonids and the Geminids, this shower is expected to be less spectacular due to lower activity and unfavorable position of the radiant to a country near the equator like the Philippines. Nevertheless, the moonless night during January 4 and 5 enticed me to give it a chance.
We chose to observe in Marikina City, at a friend’s house which has a roof deck. From there, we had a fine view of the north and eastern sky wherein most of the Quadrantids are expected to pass.
The radiant of the meteor shower which is found a little below the Big Dipper and beside the constellation Bootes, was set to rise at around 1AM of January 4. While waiting, we spent the time preparing our simple reclining chairs and sleeping bag which we intend to use as a mat where we could lie down. We also set up our organization’s 4.5″ Meade Reflector — which we fondly called Datascope — to look for deep sky objects. We pointed it first at the famous stellar sisters, the Pleaides or M45, in Taurus. We enjoyed stargazing and constellation-hopping because the sky was fairly clear then.
At around 1:30 AM, I saw my first Quadrantid. 😀 It was a short and swift one having a thin trail and a pale bluish big head, typical of a Quadrantid meteor. It passed between the pointer stars, Dubhe and Merak in Ursa Major. It was an amazing scene!
After about 30 minutes, patches of clouds began to block our view. We decided to pause our observation for a while to pick up a friend who would join us.
We continued on our observation with a less cloudy sky (around 40% cloud cover) by 3:20 AM during which we saw another Quadrantid passing near Corona Borealis. Another one zoomed past by the Bootes at 4 AM.
At 5 AM (21:oo UT), during the time of the peak we saw more meteors flying across the northeast in between cloud gaps of the 50-60 % clouded sky. In my previous post, I calculated for the number of meteors that could be seen given the 50% cloud cover and 4.0 limiting magnitude using the formula given by IMO. The actual meteor count we got during the peak is 6, which was relatively comparable to the 8 meteors per hour which I had calculated. 🙂
By 5:40 AM, we also saw one artificial satellite flying from the northwest. During this time, Venus and Mercury were already shining high in the east though they seemed to disappear from time to time as clouds pass in front of them. We also took sometime to capture a few bright constellations like my favorite, Crux in the south.
We ended our observation at past 6:00 AM when the Sun started to climb up in the east. A beautiful sunrise greeted us as we finished our observation and ate our breakfast — McChicken Fillet Meal from McDonalds — courtesy of our friend Saeed, who had his birthday during that observation.
The following night two of my fellow UP AstroSoc friends — Bea and Aaron — went to Seven Suites Hotel Observatory in Antipolo City, accompanied by some of our UP AstroSoc associates, to observe the Quadrantids from there. The sky there offers a more favorable viewing condition because it was farther from the light-polluted city. They were even lucky to have less cloudy sky during that night. 🙂
Below are some of the pictures taken during their observation at the Seven Suites Hotel Observtaory. All images are by Bea Banzuela.
I never expected that this event would turn out to be another memorable and fun observation. 🙂 Thank you, UP Astrosoc!
To all those who were able to say hello to this year’s Quadrantids, congratulations and good luck on your observation of the next meteor shower. 😀
The year 2011 will begin with an eye-catching sky show for well-placed observers when the annual Quadrantid meteor shower hits its peak during the first week of January. The new year promises to be a great one to see the Quadrantids since the moon, which can sometimes outshine the display, will be completely out of the picture.
This shower has one of the highest predicted hourly rates of all meteor showers, comparable to the two great annual showers, the Perseids and the Geminids, occurring in August and December respectively. However unlike the Perseids and Geminids, the Quadrantids peak is very narrow, occurring over just a few short hours. (You can read the IMO’s rather technical summary of the 2011 Quadrantids here.) Quadrantid meteors are of medium speed : slower than the Leonids and Perseids, yet faster than the Geminids. They usually appear bluish, accompanied by fine, long spreading silver trains.
This annual celestial event is active from January 1st through January 10th and peaks on January 4th. The peak is defined as the moment of maximum activity and the most meteors can be seen by observers.
The predicted Zenith Hourly Rate for this shower is around 120. According to British meteor astronomer Alastair McBeath, the narrow peak is predicted to occur some time between 2100 (UT) on 3 January and 0600 (UT) on 4 January 2011, however the radiant* of the shower – the now-defunct constellation Quadrans Muralis – is very low in the evening hours, rising higher towards dawn. Current sky maps place the radiant near the constellation Bootes.
Most almanacs are highlighting 8 p.m. EST Jan. 3 (0100 GMT Jan. 4) as the “most likely” time, because that is about when Earth is expected to pass through the densest part of this meteor stream, based on observations dating back to 1992. But McBeath points out that other investigations have found that the Quadrantid rates can vary from year to year, so that its peak timing may not be consistent.
If the 0100 prediction is correct, then the best chances of seeing the peak of the 2011 Quadrantids would be for Europe east to central Asia, where the radiant will be rising in the northeast during the morning hours of Jan. 4.
Quadrantids Viewing in the Philippines
Time Zone: UTC/GMT +8 hours
Best time to observe:
2:00am – 05:30am (PHT) on January 4 and 5, 2011
Shower rate: 60-120 per hour
The radiant will rise due N and get to its highest before dawn due E, so look roughly in a NE direction to maximize your chance of seeing some Quadrantids. As always with meteor showers, don’t use binoculars or a telescope – your naked eyes are best.
|Where are you observing from?||Limiting magnitude||Number of Quadrantids per hour if peak occurs at 21:00 UT Jan. 3 (5 AM PHT Jan. 4)|
|50 % cloud cover (actual weather forecast by Wunderground.com)||0 % cloud cover (perfect clear sky condition)|
|Very light polluted city center||3||4||8|
|Dark Sky Site||6.5||49||99|
|Note: These values were computed using the ZHR and formula by IMO.
Actual Hourly Rate = (ZHR x sin(h))/((1/(1-k)) x 2^(6.5-m)) where
h = the height of the radiant above the horizon
k = fraction of the sky covered in cloud
m = limiting magnitude
Using Stellarium (a free planetarium software available from here), I estimated the height of the radiant at 5:00 AM PHT for the Philippines to be at around 56 degrees above the northeastern horizon. I also assumed two values for k to illustrate the difference between seeing meteors during a 50% cloudy sky and a perfect clear sky condition. Special thanks to Steve Owens — a professional science communicator, writer and astronomer — for giving me a guide on how to compute for the number of meteors that could be seen during the peak of this shower. Some parts of this article were also taken from his very informative Quadrantids blogpost that could be found at the website http://darkskydiary.wordpress.com. UK observers may consult his post to find out what they might see during the Quadrantids Meteor Shower there.
Weather forecast for Manila, Philippines
(includes % probability of precipitation and % cloud cover)
No matter how many meteors are observed during the 2011 Quadrantids Meteor Shower, just remember to have fun and use this as a learning experience. 😀
Enjoy and clear skies to all!
*Radiant – point from where the meteors appear to come from throughout its peak
- Wunderground.com (for the weather forecast)
- SpaceDex.com (see the viewing guide for your location)