Cosmic Spectacle: Moon At First Quarter Presents Grand View

Our closest neighbour in the night sky, the Moon, can be seen in spectacular detail tonight and the night tomorrow! All you need is a pair of binoculars. (Remember the recent supermoon spectacle? No? Here’s a memory refresher.)

The moon reaches its first quarter tonight. At this time, it will be half lit by the sun’s rays, making it ideal for watching using small telescopes or a pair of good binoculars. The time tonight is roughly 10:00 PM, but the spectacle will go on for a few hours beyond that. You’ll have to be lucky enough to get clear skies and a place with very little light pollution.

What to look for?

The moon, if properly viewed, can be seen in different hues of blue as one scans from the top to the bottom. Notice especially the line separating the dark and the bright regions (which can be quite sharp on the moon, since there is no atmosphere), called the terminator’. The best views are got along this line. Notice the shadows cast due to the craters, which are especially prominent at the terminator. The craters will be visible is stark detail; you may even be able to work out the depth of the crater by the length of the shadow cast. The features will get more washed out as you move towards the more brightly lit portion of the moon, since the sun rays are more direct there, casting no significant shadow.

Look out for the craters and mesmerizing ridges, right on the line separating the dark from the lit regions.

The craters are results of billions of years of asteroid bombardment, preserved in pristine form due to the lack of an atmosphere or water on the surface. It is like looking back in time. Astronomers identify two main features on the moon the flat plains or maria’ (Latin of the word mares’) and the mountainous region. The mares lie to the north and are the results of prehistoric, and now dead, volcanic activity, which resulted in expansive lava flows. The mountainous region lies towards the south and this is where you’ll get the real joy of watching the features.

Bitten by the Photography bug?

Photographing the moon is not as simple as one thinks. The most common mistake is setting a high exposure time (i.e. a low shutter speed), which ends up wiping out most details and gives you a bland white disk. The surface of the moon, remember, is directly lit by the Sun and is as bright as an open field at midday. Set a shutter speed of about 1/500 or 1/600 seconds; use of tripod is unnecessary. Use the maximum optical zoom (not digital, please) that your camera can afford and go ahead! Experiment with settings to get the best results. It is usually a good idea to get a high contrast and low brightness photograph. You can always bump up the brightness using a photo-editor. Concentrate on the regions near the terminator they’ll give you the best shot.

If you think you’ve always seen the moon and found nothing magical about it, look at it more closely this time. It’s one of the most beautiful sights in the night sky. Bear in mind that you’re looking back billions of years!

Published by

Debjyoti Bardhan

Is a science geek, currently pursuing some sort of a degree (called a PhD) in Physics at TIFR, Mumbai. An enthusiastic but useless amateur photographer, his most favourite activity is simply lazing around. He is interested in all things interesting and scientific.