Occultation

Big goings on in the heavens tonight as the Moon moved in front of Mars and hid it for about an hour, and event known as an “occultation.”

(Was Mars hiding, or was the Moon blocking it? Who’s to blame? What was happening on Mars during that hour that the Martians didn’t want us to know about from Curiosity? Inquiring minds…)

I didn’t have the time to spare to pull out the big telescope and get it set up, but that didn’t stop me from taking time to watch and pull my camera and a video camera and a couple of tripods out. There are some truly spectacular pictures and videos out there from some of the big observatories (see Griffith Observatory, for example), but these are my “fast & dirty” results.

Before we get into the sequences, a note about basic physics and optics. The short version: the full Moon is 3.75 gazillion times brighter than Mars. So trying to take pictures that show the Moon, you need a very short exposure, in this case, 1/4000 second, the shortest exposure my 17-year-old Canon DSLR can do.

But then you can just barely see Mars. To show Mars clearly, you need a much longer exposure (1/160 second) which leaves the Moon as a white, featureless blob, looking more like the Sun.

Somewhere in the middle, if you’re lucky, there is a picture that gives you some bright, washed out detail on the Moon while also still showing the planet 50,000,000 miles away.

First, screen captures from the video camera. It has a great 20x optical zoom, but the resolution is quite a bit less than the DVR or any commercial quality video camera. Still, given five minutes of setup, these aren’t bad. These are small, low-resolution files, but they make a nice progression.

Prior to the occultation, with Mars to the lower left of the Moon, at about the “seven o’clock position”:

I was having some real problems with the tripod malfunctioning, so I’m amazed that I caught this at all! These captures are all about 30 seconds apart.

About an hour later, coming back out at about the “two o’clock position”:

These photos are about a minute apart.

Secondly, with the big camera, I didn’t get much worth sharing when Mars disappeared, but when it was reappearing I did much better (remember to click on the photos to see them full sized!):

Meanwhile, through binoculars, this was an amazing sight! I hope you got a chance to see it for yourself!