About the Perseids meteors and the Pleiades open cluster…

As you may know, the last 2 days the Earth has been bombed by dust grains and boulders. These are remnants from the dust tail of a 26km tall comet which flies by every 130 years or so. Every year on August 12-13 the Earth travels through this dust tail which slams into our atmosphere at 58km/second, leaving behind brilliant glowing tails in the night sky. These are known as shooting stars or meteors and as many as 130 of them per hour can be seen under dark skies.

But skies aren’t that dark when the meteor shower coincides with a super Moon, as happened 2 days ago. This super Moon appears when the full Moon (which is in an elliptical orbit) is on its closest point to Earth. So aside from being at its most illuminated phase, it also appears brighter because it is as close to us as it will ever get. On a late walk 2 days ago, the Moon appeared as a small Sun, brightly illuminating the environment as though it was daytime. (Ok, not as though it was daytime, but it surely wasn’t dark…)

Unfortunately for us, the Moon brightened the night sky so much, that it was very hard for the meteors to stand out and the amount of visible meteors was estimated at a peak rate of 58 per hour. So compared to the 122 per hour of 2 years ago, this year’s Perseids meteor shower (yep, that’s what it’s called) wasn’t that spectacular. Below is a post processed attempt to photograph some very bright stars near the moon to illustrate the super Moon’s brightness.

Supermoon over illuminating the night sky

Super Moon over illuminating the night sky

In other news….. A few weeks ago I posted this photo of the galaxies M81 and M82:

Spiral galaxies M81 and M82 in Ursa Major

Spiral galaxies M81 and M82 in Ursa Major

In this photo, you can see that the galaxies are just too faint and small (only a few pixels big) to be properly photographed with a 80mm lens. So I imaged them through my telescope at 650mm focal length to get a well magnified view of the pair. Finding them had been difficult in the past, because they look like faint smudges through my 90mm refractor. This night however, I saw them almost instantly and took 30 0.5 second images with the DSLR on the 130mm telescope.

Galaxies M81 and M82 imaged through the telescope in 30 x 0.5 sec short exposures

Galaxies M81 and M82 imaged through the telescope in 30 x 0.5 sec short exposures

As you can see, the galaxies are quite faint and difficult to extract from the background noise. Nevertheless, in this image the galaxies are more pronounced than in the wide field image and the cigar shape of M82 is clearly visible.

Late at night, or very early in the morning, I can see the Pleiades open cluster from here. The Pleiades cluster (Messier 45) is the brightest open cluster we can see and is clearly visible to the unaided eye. This is what M45 looks like in a stacked image of 5 x 4-second exposures with an 80mm lens:

Open cluster M45 (Pleiades) imaged with 80mm lens in 5 frames of 4 seconds

Open cluster M45 (Pleiades) imaged with an 80mm lens in 5 frames of 4 seconds

And this is the same cluster imaged through my f/5 reflector telescope:

Open cluster M45 (Pleiades) through 650mm f/5 telescope

Open cluster M45 (Pleiades) through 650mm f/5 telescope

As I have no automatic guiding system yet, I had to keep the exposure time limited to 0.5 seconds and couldn’t capture the blue-ish glow faintly seen in the 80mm photo. Someday I hope to take a longer exposure of several minutes to resolve the brilliant blue reflection nebula that surrounds the stars.

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