Variable Stars

With a Motive for expanding our knowledge of Astronomy, the club decided to get together every Thursday for discussions on the recent events in the area. The first one of such Thursdays saw a discussion on variable stars. Basically, Variables are those objects in the night sky whose apparent brightness (i.e. as seen from earth) changes over time. The changes may be due to a variation in the star’s actual luminosity, intrinsic variables or due to variations in the amount of the star's light that is blocked from reaching Earth, Extrinsic variables.

Our very own pole star or Polaris belongs to the class of Variable Stars, accurately, it is part of the Cepheid variables, a class of pulsating stars that swell and shrink extremely regularly. Generally in each subgroup of the class, a fixed relation holds between period and absolute magnitude, as well as a relation between period and mean density of the star hence enabling astronomers to gauge the distances of such stars from the earth.

Like a Diamond in the Sky

...Like a Diamond in the Sky"





I remember looking up at the sky when I was a kid and had no idea what the thousands of dots in the sky were. They looked like tiny pin pricks which showed bits of some holy daylight from beyond the otherwise dark night sky. And that was probably the beginning of a four-year old’s fascination for the night sky; the thousands of bright pinpricks –the twinkling little stars. For all of you out there, who feel or have felt even the tiniest of inklings of awe and wonder for the vast dark night sky at some point of time; I’m sure you have your own story to tell.

Throughout man’s existence on the planet, since the time of the early Neanderthal man, he has tried to explain what the sky, the pinpricks meant; what they implied. We had our share of men –astronomers and physicists who strived to solve the mysterious unexplained, right above them in the sky.

“Where does it come from? This quest, this need to solve life's mysteries, of the simplest of questions can never be answered. Perhaps we'd be better not looking at all, not delving, and not yearning. But that's not human nature, not the human heart. That is not why we are here.”

We will keep looking. We will keep searching for answers. We will always be awed by themahakaash. We will keep looking at the constellations, the stars, the planets, the nebulae, the thousands of pinpricks and wonder. And be amazed now, tomorrow, for many many years to come.

***

Men came and went. Theories came and went. Models of the Universe explaining why the night sky is the way it is, were given. Few of them accepted. Even they went. The only thing that stayed the way it was, was the sky and man’s fascination for the unexplained.

For the thousands of bright pinpricks in the sky...

Transit of Venus, 2012

The next transit of Venus will occur on June 5–June 6 in 2012, succeeding the previous transit on June 8, 2004. After 2012, the next transits of Venus will be in December 2117 and December 2125.

A computer simulation of the transit as seen from Beijing,China



Where visible

Where the 2012 transit will be visible

The transit will be best viewed from the Pacific Ocean. North America will be able to see the start of the transit, while South Asia, the Middle East, and most of Europe will catch the end of it. The transit will not be visible in most of South America or western Africa. The regions from which the transit is visible are shown in the map to the right.

When visible

Total Lunar Eclipse -- 12 December

These are the Photos we Clicked at India Gate, New Delhi , India on 10 December Lunar Eclipse.