Tutorial on Background Gradient Removal with GIMP


Made a quick tutorial on how to remove background gradient with GIMP

You need the GIMP Astronomy Plugin

NASA Juno Mission Trailer: JOI


Space-thriller themed mission trailer

Secrets lie deep within Jupiter, shrouded in the solar system’s strongest magnetic field and most lethal radiation belts. On July 4, 2016, NASA’s Juno spacecraft will plunge into uncharted territory, entering orbit around the gas giant and passing closer than any spacecraft before. Juno will see Jupiter for what it really is, but first it must pass the trial of orbit insertion. For more information: http://www.nasa.gov/juno and http://missionjuno.swri.edu

Backyard Astronomers Capture Impact on Jupiter


With Earth having passed between Jupiter and the Sun on March 8th, we have some of the finest observations of the Jovian planet.  It’s only normal to have a few backyard astronomers setting their sights on the largest planet (myself included, still got unprocessed videos from March 27th).  However Gerrit Kernbauer was lucky enough to record an unusual event: something slammed into Jupiter!

Phil Plait of Bad Astronomy reported that Gerrit Kernbauer with his 20cm telescope in Austria, captured on March 17th what appeared to be an impact of sort.

The issue was to confirm that it was an actual impact, and not some other natural effect or electronic noise in his setup.  What better than to have a second independent observation, and that came from John McKeon with a 28cm telescope in Ireland.

Maybe I should go take a look at my videos on Jupiter from March 27th just in case…  Actually with my 80mm telescope,  I don’t think it would have picked up such an impact.


Tripod and a Camera? Make a TimeLapse


You don’t need a telescope to enjoy astro-photography.  All it takes is a camera, a tripod and a timer remote controller to take interval images without you having to be there.  I know that most of the image taking is done with the camera connected to a computer.  But this remote controller allows for control of the shutter in the BULB setting without a laptop.  See it as a “grab-n-go”, travel-light type of accessory to the camera.


Set it up to take a large sequence of shots and you got the makings of a timelapse video.  Because there is no tracking with the tripod, keep the exposures under 10 seconds.  Then use video editing software like Microsoft Movie Maker to covert all those images into a video (see my article here).

It’s always interesting to analyse your frames to determine what you’ve capture, to identify key or important elements.

Wide field of the sky, mountains and horizon from a Montreal south sore suburb. March 4th, 2016. Benoit Guertin

Wide field of the sky, mountains and horizon from a Montreal south sore suburb.
March 4th, 2016. Benoit Guertin

Unfortunately, my camera battery wasn’t fully charged, and the cold drained it quickly, therefore only got about 100 frames in.

The Sun in Like You’ve Never Seen Before


A few weeks ago NASA released a video in stunning 4K quality showcasing some of the sharpest and most detailed views of the Sun at different wavelengths. These images were captured by NASA’S Solar Dynamic Observatory launched in space in 2010.

As stated in the introduction,  each minute of video takes 10hrs in the hands of specialists to process. Not too bad considering that I’ve sometimes spent hours to produce a single image.

Reference :NASA

Missile Launch Over San Francisco – Not Astronomy, but Cool Results


Not a UFO!  Last weekend the US Navy launched a Trident II D5 strategic ballistic missile from USS Kentucky (a Ohio class SSNB) off the southern coast of California.  Justin Majeczky and a friend were lucky enough to be shooting a time-lapse video over the Golden Gate bridge when they noticed the missile launch.

While not an astronomy target, capturing missile or rocket launches, especially at night lends itself very well to astro-photo gear, setup and software.  And nighttime launches often provide nice results, especially after sunset as the exhaust plume reflects sunlight high up on the atmosphere.  Can also trigger the formation of noctilucent clouds.

If you live in near a spaceport, or near a naval war exercise, tracking and capturing a missile or rocket launch with your gear can be rewarding.

Taurid Meteor Shower Already Producing Some Fireballs


While the Taurid Meteor Shower is expected to peak on November 11th and 12th for the Northern Hemisphere, some fireballs have already been observed and recorded.

The following video was recorded in Bangkok Thailand just before 9pm local time November 2nd

And a few days prior to that the following was captured in Poland on October 31st.

These fireballs as they streak across the sky often produce color due their chemical composition and the heat generating entering the atmosphere.  Some may even leave behind a smoke trail that will persist for some time.

The Taurid Meteor Shower are remnants of a large comet that probably got broken up by repeated close encounters with Earth and other planets 20,000 to 30,000 years ago.

Cassini’s 48km Close Approach to Saturn’s Moon Enceladus


Today the Cassini spacecraft made a close approach and dive through the plume of icy spray from Enceladus, Saturn’s sixth largest moon.  What surprised me was the low altitude flyby: just 48km from the moon’s surface.

OK, by aircraft standard a 48km altitude is still way up there as commercial aircraft operate at an altitude of 10km, and even the famed U2 and SR-71 spy planes designed to fly above surface or air launched missiles top out at 20 and 25km altitude respectively.  But for a multi-billion dollar spacecraft this is quite low due to the high risk.  Low Lunar Orbit used during the Apollo missions were at a 100km altitude, and all the hype on New Horizons Pluto flyby, it was at a distant 12,500km pass.  OK ESA’s Rosetta spacecraft was maneuvered down to 29km around comet 69P, but has since moved out to a safer 300km orbit.

Looking forward to seeing what comes out of Cassini’s E-21 flyby.

Source: JPL’s Cassini E-21 Flyby Page

Jupiter in 4k Ultra HD


NASA has just released a video rendered in 4K Ultra HD of Jupiter from images captured by the Hubble Space Telescope.

Learn more about this video: http://www.nasa.gov/press-release/goddard/hubble-s-planetary-portrait-captures-new-changes-in-jupiter-s-great-red-spot


Time Lapse Video of Lunar Eclipse


Stitched together the 330 photos of the September 27th Lunar Eclipse into a video.

A few things to note.  The Moon “jumps” a few times in the video, and I now realize that it’s due to my presence on the wooden deck is sufficient to cause the telescope to shift ever slightly.  Also I didn’t really take time for proper polar alignment, I was a good 5deg off and had to re-align during the total eclipse because the tracking was not perfect.  And last, some cloud cover rolled in so I wasn’t able to capture the tail end of the eclipse.

Nevertheless, still much better than the few frames I captured back in 2008.

For the curious of the camera setting.  The start with the full moon is taken at ISO 200 1/320sec and then increased up to 3.2sec exposures at ISO 400 during the eclipse.