Starry starry Night... Summer Triangle, Meteor Showers and Holidays

Salam Aidilfitri to my friends who are celebrating the Eid Festival. This week in August has so many things going on that I forgot to wish my friends a Happy Eid. And I am still awaiting for your invitation to open houses and makan etc., hehehe (pulling a cute Puss in Boots look with a sign across my forehead saying 'thick-skinned'). 

Anyhow, with a little bit of luck, we might be able to catch 'free fireworks' from the sky, i.e. the Perseid showers. This meteor shower are the result of debris from the comet Swift-Tuttle entering our atmosphere and burning up. The night of 12th August to the morning of 13th August has been said to be the best nights to observe the celestial display, provided that clouds do not obscure the view.

The radiant (apparent origin) of this shower is in the constellation Perseus. This means that the streaks of light will appear to originate from an area of the constellation Perseus. Hence the name Perseid showers as meteor showers are always names after the constellation where the radiant lies in. From Kuala Lumpur, due to our equatorial position, the constellation Perseus does not rise above horizon until past 1am in the morning (i.e. 1am on 13th Aug) . Hence viewing would be better in the wee hours of the morning and up till dawn. Also the waxing crescent moon sets after 9.30pm, thus giving us a dark sky that is more conducive for viewing.

The Perseid radiant is just 15^o above the horizon at 2am in Malaysia (made with Stellarium software). Notice that the direction that Perseus rises from is north-easterly. 15^o is approximately the distance between your pinkie and index finger stretched out when held to the sky; so if there are hills (like viewing from KL towards north-east), you still won't be able to see the radiant at 2am unless you are at Genting Highlands!

If you cannot see the radiant point it does not mean that you cannot see the shower. Rather, you will only see very much less trails than the average count. It is just like looking at a fireworks display that is blocked by a row of trees, you will only see the fire trails that travel higher that the treeline. If you want to locate the radiant, you can do so following the diagram below, and only after 2am +8GMT (unless you can see 'through' the horizon and Earth).

The Perseid radiant at 4.15am on 13th Aug 2013 as viewed from KL. If you want to look for the radiant, you can either find the Seven Sisters (Pleiades) aka Subaru and follow to the leg of Perseus up to his face (count up 7 stars), and right in front of the face, and at the foot of Cassiopeia, would be the radiant. If not, the W-shaped Cassiopeia is easier to find. Just follow through the zig-zag with another step and you would've have arrived at the radiant.

Besides the shower, one can also observe the Summer Triangle, made up of the stars Altair, Vega and Deneb. These are the stars in the constellation Aquila, Lyra and Cygnus respectively, which in Chinese mythology represents the Cowherd, the Weaver Girl and their bridge of magpies (here's an article on the Cowherd and the Weaver Girl I wrote last year). It so happens that 13th August 2013 is the 7th day of the 7th month of the Lunisolar calendar, the Qixi Festival. Thankfully the Summer Triangle rises very much earlier in the night, and the best time to view it spans through a duration of several months so one does not have to stay up late or wake up early to see it nor risk missing it due to cloud cover or poor viewing conditions.

The Summer Triangle of Vega, Altair and Deneb. Stellarium image for 8pm Malaysian time as viewed from KL.

So here's to the month of August, a month of celebrations with so many festivals and celebrations, from Eid, National Days (Singapore - 9th, Malaysia - 31st, Indonesia Independence - 17th), Qixi, Hungry Ghost and most importantly to kids...school holidays.

The Three Lucky Stars is on Orion’s Belt

Chinese New Year is just around the corner and one of the commonly seen symbols associated with CNY is the Three Lucky Stars. These three very distinguishable gentlemen are seen on red packets, New Year cards, wall decorations and decorative statues and even on joss paper. There are many versions on the origin and representations of these Three Lucky Stars.

One version is that the Three Lucky Stars or Fu Lu Shou (福禄寿), are high ranking deities, namely:

Fu – Lord Emperor Zi Wei (北極紫微大帝)

Lu – Lord Wen Chang (for academic blessing 九天文昌帝君)

Shou – Lord Emperor Nan Ji (南極長生大帝 for longevity)

Another belief is that they are reincarnated spirits and are represented by the three stars on Orion’s Belt. Remember Men In Black and the phrase “the Galaxy is on Orion’s Belt”? Well, there are no galaxies on his belt, but those are the Three Lucky Stars.

Stellarium rendition of Orion. The three stars of the belt are Alnitak, Alnilam and Mintaka. Notice that the red giant star Betelgeuse is on his armpit.

The constellation of Orion is one of the constellations that make up the Winter Circle or Winter Hexagon. The vertices of this Winter Hexagon/Circle are made by the stars Rigel (in Orion), Sirius (Canis Major), Procyon (Canis Minor), Castor or Pollux (Gemini), Capella (Auriga) and Aldebaran (Taurus).

The Winter Circle/Hexagon. The red arrow from the Three Lucky Stars (Orion's Belt) points to Aldebaran whilst the yellow arrow points towards Sirius. Hence the Belt can help you locate these two other stars.

This asterism of stars becomes prominent during the winter months, from December to early March in the Northern Hemisphere. The hexagon encircles the Red Giant star Betelgeuse of Orion. The smaller, Winter Triangle has its vertices made up from Betelgeuse, Procyon and Sirius.

Another Stellarium rendition of the Winter Circle/Hexagon (in blue/cyan) and the Winter Triangle (in red) . The Winter Triangle consist of Sirius, Procyon and Betelgeuse, with the vertex point of Betelgeuse pointing to Aldebaran.

Back to Orion, or rather Orion’s Belt; the constellation appears to rise and set earlier as the months move from December to March. It is said that in China, the Belt appears to reach its highest position in the sky near midnight around the eve of Chinese New Year, (最高點), thus heralding the arrival of a new year.

Note the sword of Orion - another group of stars in a somewhat straight line that lies somewhat perpendicular and below the belt. 

Orion as viewed almost overhead from Ampang, Selangor. The three stars of the belt can be easily seen together with Rigel (blue-white in colour) and Betelgeuse (reddish-yellow). Also visible is the 'sword' of Orion. Compare this picture with the one above it (rendition from Stellarium) can help you find the stars.

Some believe that the practice of welcoming the Wealth God on New Year’s Day is actually the practice of welcoming the Three Lucky Stars (福禄寿) or Orion's Belt. As monetary gains becomes the focus of the practitioners, the two other lucky stars were omitted from the invitation practice.

Can you see Orion or Orion's belt on this photo? The belt is on the middle top part of the photo.  Look at the photo below to compare.

The view of Orion over the bright lights of KL city skyline with the three stars highlighted  This is when Orion is setting in the West.  Rigel, Betelgeuse, the sword, and even Aldebaran can be seen despite the high light pollution on the skyline.

These three stars can be easily spotted with the naked eye, together with the rest of the stars on Orion on a clear night during the boreal winter months. Even the bright lights of KL city cannot mask the stars as they set in the West, early in the morning. So take a look and see if you can see the Three Lucky Stars for the New Year. Happy Chinese New Year!

The Night of the Sevens

I would like to wish Selamat Hari Raya Aidilfitri to all my Muslim friends. This is indeed a month of celebrations. Whilst I am still getting my share of open houses and yummy rendang, let me share another event occurring in this month. Tonight is the Night of Sevens, a festival that is celebrated in various Eastern cultures including China, Japan, Korea and Vietnam.

This celebration has its roots in the asterism of three bright stars (called the Summer Triangle) visible in the Nothern Hemisphere during the end of summer. The three stars that form the triangle define the vertices of three constellations, namely Aquila, Cygnus, and Lyra, the stars being Altair, Deneb, and Vega respectively.

In Chinese folklore, this asterism in the northern sky has evolved into a sad romantic tale of the Cowherd and the Weaving Maiden. Very much like the forbidden love of Romeo and Juliet, this tale features the separation of the loving couple by disapproving parents. There are many variations to this tale, but all of them have the same ending, which is a slightly happier ending when compared to that of Romeo and Juliet.

In one version of the Cowherd and Weaver Girl story, the weaver girl/maiden is one of the seven daughters  (some say granddaughter) of the Queen Mother of Heaven. Zhi Nü (织女, literally the weaver girl) is good at weaving the sky and the colourful rainbow fabrics of heaven, thus is very well-liked by her mother. As with all young girls, the seven sisters decided one day to take an excursion to Earth, to escape the boredom of privileged life in heaven and also watchful eyes of the Queen Mother (who is depicted as somewhat an overbearing mother – like the Empress Dowager). And so on Earth, they found a beautiful pond and decided to go for a frolic in the cool water. Leaving their dresses by the bank of the pond, the girls had wonderful ‘pool party’.

After a while, the girls got tired of the mortal world and when it was time to leave, all the sisters except the weaver girl could do so as her clothes had been blown away and had fallen into the hands of a passing cowherd. The kind cowherd however, returned her clothes, though we wouldn’t have a clue as to what was going on in his head, faced with a wet, naked fairy from heaven. Alas, when their eyes met, he was truly smitten and likewise, it was love at first sight for her. They decided to get married without the permission of the Queen Mother, knowing that she would forbid fiercely as he is a mere mortal and just a cowherd.

Happily married, they had two children. She was a caring and hardworking wife and he was a good cowherd and worked hard in the fields. Meanwhile in Heaven, the denizens of heaven had just noticed the missing maiden when they realised that there was no one weaving the wonderful fabric of the skies. Though Zhi Nü was only gone for a day in heaven; this time was equivalent to two years on earth.

Angry that Zhi Nü was neglecting her duties, The Queen Mother searched for her high and low, and finally found her on Earth, married to a mere mortal and living in a pathetic hut. Now fuming with anger, she gave the ultimatum to Zhi Nü: Come back to heaven or the cowherd and the village will be destroyed. Fearful for her husband and children’s safety, she had no choice but to leave her beloved behind.

The cowherd with his two children chasing after his wife, the Weaver girl. Image taken from http://www.yholiday.com.

Shocked and racked with grieve that her wife had floated away to the heavens, he was equally shocked when his old, faithful buffalo talked and advised the astonished cowherd to kill him and that his hide be used to ferry the cowherd to the sky so that he could be with his wife again. Apparently the buffalo was a heavenly officer punished by the Heavenly Emperor and was cast to Earth. With a heavy heart, the cowherd had to kill and skin his faithful buffalo and prepared himself for the journey. He placed each of his children on a basket and passed a yoke through the baskets, carrying them upon his shoulders. Flanked by a child on each side, he rose to the heavens after putting on the hide of his talking buffalo.

Slowly he could see that he was getting closer and closer to his lovely wife, Zhi Nü. Just as he was about to reach the maiden, he was noticed by the still seething Queen Mother. Disgusted with the cowherd’s attempt to reach her daughter, she quickly drew a hairpin from her headdress and with the pin, proceeded to scratch the heavens, creating a silvery river that blocked the cowherd from reaching the maiden.

And so the two lovers stood on the opposite banks of a deep and fast flowing celestial river, in grief. The sad cries of the maiden, and that of her loving husband and children, who were so close and yet beyond reach however, touched the hearts of the gods in heaven and all of the magpies in the world. And so every year on a late summer’s night, all the magpies would be allowed to soar up to the skies, and make a bridge across the Silver River so that the lovers would be reunited and be a happy family again for that one night.

A happy family portrait for the Weaver Girl and the Cowherd. Image taken from http://forum.petalia.org/topic/36258-nguu-lang-chuc-nu/. Another name for this Festival of the Night of Sevens is the Magpie Festival, after the magpies that formed a bridge (鹊桥) to bring the lovers together.

The cowherd is the star Altair (α-Aquilae) on the constellation of Aquila, the maiden is the star Vega (α-Lyrae) on the constellation of Lyra and the magpies are the stars of the constellation of Cygnus (the Swan), with Deneb (α-Cygni) being the brightest and marks the position of the chaperone (a fairy or deity) who guides the formation of the bridge. The two children are Tarazed (γ-Aquilae) and Alshain (β-Aquilae), flanking the star Altair on both sides (the children carried in two baskets on a yoke).

On summer’s end, the stars appear bright on the skies of the Northern Hemisphere and with the alignment; it appears as if the stars in the constellation Cygnus is bridging the Milky Way (Silver River) to bring them together. Also, the Milky Way appears dimmer at this time, hence allowing for the bridge of stars to be seen clearly. Thus, one can see how this asterism can be linked with the tale of the magpies, the self-sacrificing maiden and the cowherd with their pining children.

A computer rendition of the Northeastern sky at 8.39pm on 23 August 2012 as seen from Kuala Lumpur Malaysia, with no atmosphere, no ground and azimuthal grid. The Milky Way is the fuzzy white area where the light blue line runs through. The Cowherd and his children are labeled and the stars that form the magpie bridge are marked with green arrows. Image captured from Stellarium software.

The same image, but with the imaginary lines to connect the stars for each constellation. The light blue arrow points to the 'row of magpies' and the green arrows roughly indicate the sides of the 'Silver River' that runs through the sky.'

On the night of the seventh day of the seventh month in the lunisolar calendar, this double seventh night is celebrated as the Qixi Festival (七夕节). It is a day for young maidens to pray for a good husband, and to demonstrate their domestic skills, very much like the weaver maiden, in hopes of attracting a good man. Thus this festival is sometimes incorrectly referred to as the Chinese Valentine's Day. The Japanese festival of Tanabata is the equivalent to the Chinese Festival to Plead for Skills, another name for the Qixi Festival, which was adopted by the Japanese in the Heian period. Here the maiden is Orihime and the cowherd, Hikoboshi. Whether known as Qixi to the Chinese, Tanabata to the Japanese or Chilseok in Korea, this asterism of stars had become a popular folktale and a festival in its own right. We may never know if indeed the two lovers get to meet once a year or not, but hopefully all lovers out there wouldn’t have to wait once a year to be together with each other.

The same image as above, but with constellation art superimposed - Vega in the constellation Lyra (the Lyre), Altair in the constellation Aquila (the Eagle), and Deneb in the constellation Cygnus (the Swan).

This is what you will probably see, without clouds but with light pollution - just three dots marking the vertices of the triangle.

If you want to observe the above asterism tonight (23 August 2012), the constellation Lyra, Aquila and Cygnus rises in the Northeasterly quarter in Malaysia as early as 5pm. So by 8.00pm, Deneb would be 30^o above the horizon. The only obstacle to observing these stars are severe light pollution, haze and cloudy skies. So people in KL might be a bit out of luck. One can also use the free software called Stellarium to help locate the stars in the sky, or to reminisce the love story of the Weaver Maiden and the Cowherd.

UPDATE: Suprisingly, the skies were clear over KL and at around 9.11pm, I could see the stars Vega, Altair, Deneb as well Albireo with no difficulty even though coming from a lighted room. The triangle can be clearly made out (marked with white lines), with Vega at the same level with Albireo (the blue line).

Though not a real picture of the Summer Triangle, this Stellarium image is just like what I saw tonight. The triangle formed by Vega, Altair and Deneb could be easily picked up on the sky. Then I noticed Albireo that was in line with Vega. Tarazed could also be seen beside the bright Altair. The stars that formed the Magpie Bridge was the next thing that could also be picked up with ease, with some stars (worded blue) being a little tricky to place. Finally, the star Alshain required some time and staring into the sky to catch a glimpse of. So I managed to see the entire family, magpies and all, thanks to the clear skies tonight.

Other stars that required little or no acclimatisation to see are the stars in Cygnus (the Magpie bridge - kappa, iota, delta, gamma, epsilon, zeta, mu-1 Cygni, plus eta Cygni, with some that are slightly more difficult to make out at a glance) and the child, Tarazed in Aquila. The second child of the cowherd, Alshain required some acclimatisation to view and I had to stare into the darkness to see it. So there you have it, a happy family reunion, for the sky was clear and they didn't shed a tear (well, at least over here in KL).

The Last Transit of Venus for the Century

Here are some pictures of the last transit of Venus for this century. The next transit will be in 2117, which I guess we all won't be around to catch it.

Venus appears as a shadow (the beauty spot - a.k.a. the Cindy Crawford/Marilyn Monroe mole) on the left (about 9 o'clock) of the Sun's disk. Taken with a Sony DSC point and shoot, two pieces of DIN10 welder's glass, a cardboard shield and Adobe Photoshopped to remove the green cast.

Without colour correction, the welder's glass gives the image a strong green cast. The shadow of Venus is seen on the left hand side of the solar disk. This image was captured post maximum contact, at around 10am local time.

The path taken on the solar disk is a curved trajectory, because as the sun moves through the sky, the solar disk rotates with respect to the horizon. Hence the apparent trajectory taken by Venus across the solar disk is a curve and would be different depending on the location that you are viewing from. To look at what the trajectory looks like, you can go to http://transitofvenus.nl/wp/where-when/venus-curved-trajectory/ and use the flash applet provided by www.sunaeon.com to see the trajectory from your location.

An overlay of combined images taken during the transit of Venus over that of the modeled track given by www.sunaeon.com that was accessed from http://transitofvenus.nl/wp/where-when/venus-curved-trajectory/ - the combined series of images shows the 'spot' is taking a curved trajectory over the solar disk as modeled for viewing from Kuala Lumpur.

Below are a few pictures extracted from the site mentioned above to illustrate how the observed trajectory is different at different localities.

The apparent transit trajectory for Kuala Lumpur, Malaysia - this imaged was superimposed with images of taken during the transit and made into the image above this.

The apparent transit trajectory for Adelaide, South Australia.

The apparent transit trajectory for Osaka, Japan.

The apparent transit trajectory for Beijing, China - similar to the view from Osaka.

The apparent trajectory for Fairbanks, Alaska.

The apparent trajectory for Los Angeles.

If you like to see how the trajectory of Venus appears in other places, try using the flash object below. You can click on the Trajectory button to draw the calculated trajectory and change the location by clicking on the map.

The Rise of the SuperMoon

This weekend we will see the moon at its closest point to Earth for 2012. This perigee-full moon is also considered a ‘SuperMoon’, a term coined by astrologer Richard Nolle. Whilst this is not the one of the extreme supermoons in the 21st century, it is still one of the many supermoons occurrences. By definition, a SuperMoon is a perigee-syzygy, a new or full moon (syzygy) which occurs when the Moon is at 90% or greater of its mean closest approach to Earth (perigee). An extreme SuperMoon is when the moon is at 100% or greater than 100% of its mean perigee.

The rising moon on the evening of 4^th of May 2012.

The moon reaches its closest distance to Earth (perigee) at about 03.34 AM GMT on May 6 and two minutes later, syzygy occurs at 3.36AM GMT. At perigee, the moon will only be 356953 km from Earth, the closest for this year. Unfortunately for us in Malaysia, the full perigee-syzygy will occur during daylight (11.36 AM on Sunday 6 May). However, the moon would already look somewhat bigger a day before and after the perigee syzygy, and this is especially noticeable when the moon is close to the horizon at moonrise and moonset.