Transit of venus ppt pdf

TRANSIT OF VENUS(Venus moving in front of the Sun when viewed from the Earth)

Talk by:Aditya Ravi

Saturday, 27 April 13

WARNINGNever look at the sun through a telescope/binoculars/finder scope without a proper solar filter!You not only blind yourself but also may end up damage your equipment optics.


WHAT DO YOU MEAN BY “TRANSIT OF VENUS”

“When Venus passes directly between earth and the sun, we see the distant planet as a small dot gliding slowly across the face of the sun.”

The last transit of Venus occurred June 6th, 2012. The next pair of Sun-Venus-Earth alignments will be December 2117 and 2125.

If Venus and the earth orbited the sun in the same plane as the sun, transits would happen frequently. However, the orbit of Venus is inclined to the orbit of earth, so when Venus passes between the sun and the earth every 1.6 years, Venus usually is a little bit above or a little bit below the sun, invisible in the sun’s glare.

A similar thing happens with our moon. Every month the moon passes between the sun and the earth, yet we do not see a solar eclipse every month. That’s because the moon’s orbit is also slightly inclined to earth’s orbit, so the new moon is usually a little above or a little below the sun.

The pattern of 105.5, 8, 121.5 and 8 years is the pattern followed by these transits in a 243-year cycle.


METHODS OF OBSERVING THE SUN

A good quality solar filter is required Observing Visually

Eye-piece Projection on a board.

Photo Credits:Adarsh A.Srivatsa


REQUIREMENTS FOR IMAGING THE TRANSIT OF VENUS/SUN

Telescope or a telephoto camera lens with a tripod.

A white light neutral density 3.2 filter or H-alpha solar filter or Calcium K filters.

A DSLR/Webcam for prime focus photography or cellphone and point and shoot camera for a-focal photography.


COMPARISON OF IMAGES OF SUN WITH DIFFERENT FILTERS

White Light ND 3.2 Filter



H-Alpha Solar Filter

Images taken by and credits to: Steven W. RamsdenDirector,Charlie Bates Solar Astronomy Project



Calcium K-Line Filters


WHAT I USED DURING THE VENUS TRANSIT

Skywatcher 8” F/5 Newtonian Telescope

Baader ND 3.2 white light solar filter.

Canon 500D on prime focus.

Skywatcher NEQ-6 Goto Mount

Solar Tracking Mode On


THE PREVIOUS NIGHT WE HAD AMAZING TRANSPARENCY


THE NEXT DAY OUR BEST FRIENDS JOINED US (CLOUDS)


THE FIRST SHOT CAPTURED AND THE EXCITEMENT BEGINS


TECH SPECS

The Baader Solar solar film reduces the intensity of sunlight by 99.999%

Exposure time: 1/4000s

ISO 100

Exposure biasing was used in few images to control the brightness of the image.

The photos were taken at prime focus hence aperture cant be controlled.


RESULTS


RESULTS


A-FOCAL MOBILE PHONE PHOTO

Photos are taken by Sanath

Kumar with his cell-phone


Any questions?

Hope you enjoyed this presentation.

You may also contact me at [email protected]


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Art & Photos

Transit of venus ppt pdf