Sunday, September 11, 2016

Back to the clear skies.

It's been a while I have updated this blog. Lets start where I left. Satellite spotting ! . The monsoon is almost over and clear skies are not as rare as it was for last few months. Recently some of the planets have been clustering together to make conjunctions. I missed Jupiter and Venus's closest approach last month due to bad weather. Jupiter and Venus were so close that they could have been seen within the field of view of telescopes and binoculars. Apparently Venus was closer to Jupiter than Callisto, farthest of the Galilean moons.

Christopher Becke did make an attempt from the other side of the world.
I managed to catch the Saturn and Mars hovering around Scorpios.

ISS and Plane 

And an Iridium flare and ISS pass at the same time.

ISS Pass SW Sky Iridium 97 Flare

Sunday, January 3, 2016

Shooting Iridium Flares

Iridium flares are sudden flares reflected from one of the Iridium satellite which looks like a very bright (as bright as -8 magnitude) moving object in the sky , sometimes brighter than Venus (max magnitude - 4.7 ) . The satellite itself is very faint in the sky (around 6 magnitude ) which almost beyond naked eye limit and since they are moving fast they can not be caught in long exposure. (because light doe not fall on a single spot in the camera sensor). I have been lately addicted to spot and capture this.

Iridium Flare
Iridium Flare Captured From Urban Sky
 These are so bright during the flare that it can be easily seen even from the most light polluted sky. Here in this photo I could only see the bright stars. I could barely see a 2.8 mag star above 10 degree of southern horizon. Thanks to heavens-above.com and its Android app I could easily notified well before the flare and track it live just before its appearance so that I can have my camera's shutter open.


 This particular time it was close to horizon during flare (about 21 degree) so I could get both the earth and sky. I have even captured this closer to horizon where its very difficult to see faint objects.


Iridium flare
Flare just 11 degree above horizon.

  In both cases sun was well below horizon and it was evening. However I could not spot or capture this just during sunset despite being magnitude -6.7. It is claimed that these bright flares can be seen in the day time also but I think I did not look at the precise part of the sky due to lack of any star , may be it was just visible. I have got the video footage , probably I will play it over and over in my leisure to detect the bright moving spot.

Camera Settings

Since the sky was not very dark and I had to take a long exposure (more than a minute) I had to reduce the aperture of the camera to F/8 so that not a lot of light comes inside over the period of time when shutter is open , I also minimized the ISO to 100 to make the censor less sensitive. Anyway I was shooting in RAW format so that I can play around the exposure and contrast later.

Since these are polar satellites , they rise in north and set in south. So all the attempts I have done till now are in the similar place of the sky. I intend to capture one in the middle of dark sky with wide angle and along with some recognizable celestial object e.g. planets and bright stars in coming days.


Monday, December 28, 2015

Geminids 2015

3 years ago I witnessed a spectacular Geminid meteor shower. This year also we set out for a view of dark sky. Its quite tough to find such place near the city. Still we referred the light pollution map and tried to find a spot in the "green zone".

Light pollution map around Hyderabad http://darksitefinder.com/maps/world.html
Spotted 50 odd meteors throughout the night whenever I was looking up. Most of the time I think we were busy setting up telescopes, tracker and lenses.

A meteor streak during Geminids 2015
Spotted Comet C/2013 US 10 Catalina as well in the morning sky.

 
Comet Catalina C/10 US 10

Also captured some regular objects like Jupiter, its moon, Venus, Mars etc.
Jupiter
Jupiter and its moons
Plane taking off
Plane
Regulus, Jupiter, Mars and Spica dominating the ecliptic
Mars , Jupiter and Spica
One of the arms of milky way !
Milky Way
Stars moving around Pole Star (North Star)
The north celestial pole

via GIPHY

Panorama to Movie

I take a lot of panoramic pictures either with the in camera functionality or stitching later with software like autostitch. However I did not find a good way to showcase that. I upload them to Facebook or flickr sometime but justice is not done to them as its looks a very short height image to compensate for the huge width. I posted the question in stackoverflow as well.

Finally I found a simple way to do that in Mac using iMovie.

Just import the image into a new movie in iMovie and stretch the image along the timeline for the length you want the output movie to be.

That's it. Here is a sample I generated





From the following original image.


This video format is good for Facebook and Instagram where screen with is limited and panning the across the image eventually displays the while image with proper details.

Once it is in video format it can also be converted to a GIF image using any online tool. Especially sites like giphy.com lets you post to Facebook in such a way that it animates inside timeline even in mobile app (which most of your friends use).

Here is a sample GIF made out of 3 different shots during one of my stargazing session



via GIPHY


Tuesday, December 22, 2015

Hampi



I recently visited Hampi in present Indian state of Karnataka. It was capital of the Vijayanagara Empire in 14th and 15th century . It was one of the richest and largest city of its time probably richest ever after Rome and largest ever after Peking-Beijing. it was finally laid siege to by the Deccan Muslim confederacy.




Thanks to Google Maps , I did mess up the route a little bit near Mahbubnagar as you can see from my location history screenshot above. First I overshot the right turn by taking the fly over by mistake. Maps did not tell me explicitly that I have to go below the fly over. It was a long one and divider cuts are not very frequent in this highway. Secondly , inside the town maps suggested me to get down from the highway (SH 20) and get into another via taking small roads inside town. It probably did not realize that these roads are shorter but definitely wide enough for car. I should have ignored the left turn and continued in the alternative route (which is actually the highway eventually joining another highway). The learning is its worth taking a little slower route (as per maps) but one should stick to the wider option when difference is not much.


This city is situated on the banks of river Tungabhadra.

The following sound  is from famous musical pillars of Vittala temple left ruins of Hampi The British wanted to check the reason behind this wonder and so they had cut two pillars to check anything was there inside the pillars that was producing the sound. They had found nothing but hollow pillars. Even today we can see those pillars cut by the British (What I read in the internet and guide told me).

Picture of inner broken pillar.


Compete video