Friday, 1 August 2014

The Milky Way over Lone Pine

In my blog CQA I wrote that one of the reasons I continue to blog is because through blogging, I've come to know some people I would not know otherwise. This summer I visited one such person in his desert lair at Lone Pine, California.

On the first night of our stay, the moon set early behind the Sierra Nevada. The skies were clear, and the remote desert location meant that there was minimal light pollution. When I ventured outside at around 2 am, I was treated to one of the most beautiful night skies I have ever seen.

The photograph I took captures only a small section of the vista that stretched out above us, but it has a number of interesting objects. The dominant feature is, of course, the Milky Way. You can also see (parts of) eight constellations, binary stars, a red supergiant whose diameter is nearly 900 times that of the Sun, and a number of deep-sky objects (star clusters, and nebulae – interstellar clouds of dust and gas hundreds of light years wide, where new stars are being born). The deep-sky objects have exotic names like the Wild Duck Cluster and the Eagle Nebula (and sometimes non-exotic names like NGC 6441). You can also see a star cluster 87,400 light years away in another galaxy, and a dark nebula in the shape of a black horse galloping through the heavens.

Perhaps coolest of all, the photo includes the galactic centre – the theorised location of a supermassive black hole known as Sagittarius A* whose mass is over 4 million times that of the Sun. Sagittarius A* cannot be seen in the photo – or even through astronomical instruments from Earth, at least not at visible wavelengths – because of interstellar extinction by dust and gas. We know its location because it is detectable as a source of strong radio waves.

You want to know where all these cool objects are, don't you? Click on the photo for an interactive guide.

I would have unveiled this photo long ago, but Anasua coaxed me into making the guide, which took weeks of research and coding. "Reach for the stars," she said.