Friday, September 23, 2016

Autumnal Equinox 2016 as seen from Space (animated)

An Equinox is the astronomical event when both the hemispheres have equal duration and amount of sunshine.
Sun would be exactly overhead of the equator.
It happens twice in a year Spring (Summer) equinox (20 March) and Vernal (Autumnal) equinox (22 September).

Here is the view of the beautiful event from space for 22 September 2016.
I have animated it (time series for the day).
Watch the day-night solar terminator move through the earth.
Observe the equal area of sunshine and night on either hemisphere.

The visible imagery is from MeteoSat VISSR (IODC) stationed at 57deg.E longitude above equator in a geostationary orbit.





For a typical comparison of Equinoxes with Solistices, you may go through this link http://akmnscience.blogspot.in/2012/07/equinox-solstice-better-view.html


Image Courtesy: Dundee Satellite Receiving Station http://www.sat.dundee.ac.uk/

Tuesday, March 8, 2016

Solar Eclipse over Tirupati 09 Mar 2016 (simulated)

Solar Eclipse (09 Mar 2016) is hardly visible over Tirupati.

Here is an animated version (Figure (a)) of the simulation I have prepared using the free open source "Stellarium" software.

The Sun rises over Tirupati by 06:23 IST.
Meanwhile eclipse has already begun and being in penumbra region, it's partial eclipse over here.


For reference, the figure (b) of eclipse locations are shown in the figure below (scroll down) which also shows time in Tirupati during the events. 
(courtesy: timeanddate.com )

Figure (a): Animation of the solar eclipse (simulated) over Tirupati.
'E' indicates East

Figure (b): How eclipse happens world wide (courtesy: timeanddate.com)