Length of Sidereal Day

Sidereal day is the time taken by the Earth to rotate on its axis relative to the stars. Because star is so far away, this is equivalent to saying that it’s the time for the Earth to rotate 360 degrees, and the solar day is the time that it takes the Sun to go from one noon to the next noon. These two videos also describe sidereal day: So to calculate sidereal day we can put a camera on an equatorial mount and point it to Polaris.

Coronavirus Information

This article discusses about the success of Hong Kong and Singapore in stemming the spread of the coronavirus and how that holds many lessons for how to contain it in the United States: Keeping the Coronavirus from Infecting Health-Care Workers In this video, Dr. Duc Vuong explains how the coronavirus kills its victims. It is very relavant and informative. How to Make Your Own Mask

Convert Star Coordinate Using Python Floor Division // and Modulus % Operators

Below is an example of using the floor division and modulus operators to convert the RA and Dec coordinate of a star to the standard format. The calculation is done in a python notebook hosted on Google Colab. Colab is free if you have or signup for gmail. Can you guess the start’s name? Star Coordinate Jupyter Notebook


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