August 26, 2016 Friday
Bedtime Story
So we were left wondering with the question:
What is a Cepheid variable?
Cepheid variable is a star (our sun is a star too), with a characteristic feature.
It pulsates radially varying both in diameter and temperature that is seen to us apes on earth as a tiny spot changing its brightness in the night sky.
Moreover, the pulsation has a very well defined period and amplitude that may range from 1 to 50 days.
The brightness is technically termed luminosity and is essentially a measure of the amount of electromagnetic energy a body radiates per unit of time.
So the SI unit of Luminosity is joules per second or watts.
The instrument that measures luminosity is called a bolometer that was invented not too long ago in 1878 by an American astronomer Samuel Langley.
(another forgotten hero!
Just imagine what chance we have being remembered who have contributed absolutely nothing original to this planet.
I have not even passed my selfish genes.)
We shall discuss Langley and his bolometer some other night.
If you are thinking that Henrietta Swan Leavitt discovered these strange pulsating stars called Cepheid variables, you are wrong.
The first Cepheid variables were discovered way back in 1780s by men like:
Edward Pigott (English)
and
John Goodricke (another Englishman).
The first such star was seen by Goodricke in the constellation Cepheus and hence the name (in Greek mythology the King of Aethiopia just like our Lord Rama or Krishna, fancy and seductive but mythology all the same).
Constellation Cepheus though is not a mythology but a reality that was even noted by the second century astronomer Ptolemy in his Almagest.
The tragedy of Ptolemy's great work is that it has been abused on a catastrophic scale by the nonsense which is popularly known as astrology,an affront to the majestic science of astronomy.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
Bedtime Story
So we were left wondering with the question:
What is a Cepheid variable?
Cepheid variable is a star (our sun is a star too), with a characteristic feature.
It pulsates radially varying both in diameter and temperature that is seen to us apes on earth as a tiny spot changing its brightness in the night sky.
Moreover, the pulsation has a very well defined period and amplitude that may range from 1 to 50 days.
The brightness is technically termed luminosity and is essentially a measure of the amount of electromagnetic energy a body radiates per unit of time.
So the SI unit of Luminosity is joules per second or watts.
The instrument that measures luminosity is called a bolometer that was invented not too long ago in 1878 by an American astronomer Samuel Langley.
(another forgotten hero!
Just imagine what chance we have being remembered who have contributed absolutely nothing original to this planet.
I have not even passed my selfish genes.)
We shall discuss Langley and his bolometer some other night.
If you are thinking that Henrietta Swan Leavitt discovered these strange pulsating stars called Cepheid variables, you are wrong.
The first Cepheid variables were discovered way back in 1780s by men like:
Edward Pigott (English)
and
John Goodricke (another Englishman).
The first such star was seen by Goodricke in the constellation Cepheus and hence the name (in Greek mythology the King of Aethiopia just like our Lord Rama or Krishna, fancy and seductive but mythology all the same).
Constellation Cepheus though is not a mythology but a reality that was even noted by the second century astronomer Ptolemy in his Almagest.
The tragedy of Ptolemy's great work is that it has been abused on a catastrophic scale by the nonsense which is popularly known as astrology,an affront to the majestic science of astronomy.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
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