Determining the distance to a star cluster

How to determine the distance to a star cluster using its H-R diagram?

Background and Need

Having covered the background on Star Clusters, H-R diagram, Main sequence and the need to study star clusters in our previous article on estimating the age of a cluster, we will discuss about ZAMS. Zero-Age Main Sequence (ZAMS) is the locus of all newly formed stars main sequence (MS) stars on the H-R diagram of a cluster – forming a boundary to the lower left of the main sequence.

Idea

Ideas and Mathematical tools

IEEE Medal of Honor for the year 2007 goes to Prof. Thomas Kailath for "exceptional development of powerful algorithms in the fields of communications, computing, control and signal processing".

How can one work and contribute at highest level in so many varied fields? What is his recipe for success?

Estimating age of a star cluster

How can we determine the age of a star cluster using its H-R diagram.

Solving Sudoku - Tactics part 2

Continuing with the tactics for solving Sudoku from my earlier post, here is the second part of the post. Here we will discuss tactics referring to level 2 and 3. For legend and terminologies please refer the earlier post.

Superb Moon

All of us heard about the recent super moon phenomenon that took place on March 19 2011. Yes, I too witnessed the event late in the might and here is one of my pic.

Solving Sudoku - tactics

Sudoku, the puzzle of this decade,  is quite a fun to solve.!
But if you find it boring and think it is fun only as long as one can solve it.. then do take my word..

"Sudoku is lot more fun to solve when it gets harder, but only if you have the right tactics and solving strategies."

Over the next few weeks we will discuss solving tactics of varying levels and difficulties starting from the easiest to the difficult ones. We will only discuss the tactics for 3x3 sudoku ppuzzle..But before we start on that, I have a few points to make:

Calculate the day of any date

Do you want to know How to calculate the day of any given date off hand?

Then read on..

For any given date, there is a simple workable formula to calculate the corresponding day. Since for most of the times we would work with dates in 20th and 21st century, So let me just limit myself to explain a simple formula that would work for these 200 years!

Naming the days of the week

How are Days of the week named?

Continuing with the last post of why there are 7 days in a week, here I will try to elucidate the idea behind the naming and the order of the days in a week. This was the method used in the olden times (Babylonian civilization) to arrive at the names for the days and their order.