A simple stargazing tip
Posted: Mon Sep 10, 2007 9:58 pm
Without a starmap on hand, or when the stars are so unfamiliar that the common signpost are no where in sight, how do you find your way around the sky? Here is a simple trick, though it is probably not applicable to many experts here who are so well versed with the sky.
To begin, you need to know the horoscopes pretty well, for example, the horoscope of Pisces falls between 19 Feb - 20 Mar. Why is this important? In astrology, horoscopes are also known as sun signs. This is because, in ancient Greek, it was observed that during this period of time, the sun is observed to be "housed" in the constellation of that sun sign. So with this knowledge, we will be able to know the location of the sun relative to the sky just by knowing the date and the horoscope now.
However, there is one little trouble. In the past, the first horoscope is in Greek astrology is Aries. This is because during the vernal equinox, which is the day when the length of daytime is equal to the length of night time, the sun is in Aries. That's why until now, the point is still known as the First Point of Aries. However, due to the precession of the Earth, the sun is actually "housed" in Pisces during the vernal equinox. Thus, using horoscope to judge the position of the sun in the sky is not as accurate now.
However, we can still obtain a rough estimate of the position of the sun. All we need to do is to "subtract" one horoscope, meaning if this is the month of Virgo, the sun is actually housed in Leo, the horoscope before Virgo.
So how is this useful? If we know the time at which the sun sets (which in Singapore, it is about 7.20pm), we can estimate the position of any zodiacal constellation in the sky. There are 12 zodiacal constellation in the sky, each spans an approximate 30 degrees across the sky. So by knowing the zodiac that is setting, the position of any other constellation can be approximated.
Take for example, this is the month of Virgo, thus the sun is in Leo now. Hence, at 7.20pm, Leo is approximately setting, and Virgo can be found at about 30degrees above the horizon, libra at about 90 degrees above the horizon, and Scorpio is at the Zenith. At the same time, the 6th constellation from Leo, which is Aquarius, is in the rising position. Thus, if you know how the rest of the sky is relative to the zodiac, this provides a quick way to guestimate the rising time and setting time of any constellation in the sky.
To begin, you need to know the horoscopes pretty well, for example, the horoscope of Pisces falls between 19 Feb - 20 Mar. Why is this important? In astrology, horoscopes are also known as sun signs. This is because, in ancient Greek, it was observed that during this period of time, the sun is observed to be "housed" in the constellation of that sun sign. So with this knowledge, we will be able to know the location of the sun relative to the sky just by knowing the date and the horoscope now.
However, there is one little trouble. In the past, the first horoscope is in Greek astrology is Aries. This is because during the vernal equinox, which is the day when the length of daytime is equal to the length of night time, the sun is in Aries. That's why until now, the point is still known as the First Point of Aries. However, due to the precession of the Earth, the sun is actually "housed" in Pisces during the vernal equinox. Thus, using horoscope to judge the position of the sun in the sky is not as accurate now.
However, we can still obtain a rough estimate of the position of the sun. All we need to do is to "subtract" one horoscope, meaning if this is the month of Virgo, the sun is actually housed in Leo, the horoscope before Virgo.
So how is this useful? If we know the time at which the sun sets (which in Singapore, it is about 7.20pm), we can estimate the position of any zodiacal constellation in the sky. There are 12 zodiacal constellation in the sky, each spans an approximate 30 degrees across the sky. So by knowing the zodiac that is setting, the position of any other constellation can be approximated.
Take for example, this is the month of Virgo, thus the sun is in Leo now. Hence, at 7.20pm, Leo is approximately setting, and Virgo can be found at about 30degrees above the horizon, libra at about 90 degrees above the horizon, and Scorpio is at the Zenith. At the same time, the 6th constellation from Leo, which is Aquarius, is in the rising position. Thus, if you know how the rest of the sky is relative to the zodiac, this provides a quick way to guestimate the rising time and setting time of any constellation in the sky.
