Saturday, July 28, 2012

Closest Quasar

Today I have a picture of a very unique object to show you: the first quasar ever discovered. I had meant to take this picture before the transit of Venus, but the combination of poor weather and a heavy workload made it impossible. Luckily for me, Virgo was still high in the sky when I took this picture on the 11th of July.

A short note about quasars: quasars (short for quasi-stellar objects) are believed to be comparatively small accretion disks around supermassive black holes in distant galaxies. They are known as quasi-stellar objects because they appear star-like to all but the most powerful telescope due to their extremely great distances. They give off tremendous amounts of light all across the electromagnetic spectrum, from X-rays to infrared. Some also give off copious amounts of gamma rays and radio waves.

The quasar below is thought to be the closest quasar to us at 2.44 billion light-years away. Yes, that's billion with a "b". Our Milky Way galaxy is about 100,00 light-years across, so nearly 25,000 galaxies like the Milky Way could fit between this quasar and our galaxy. And that's the closest quasar to us. Most quasars are much further away, and due to their extreme luminosity are some of the farthest objects visible in the universe. This quasar, though, is likely the farthest object you could reasonably expect to see through an amateur-sized telescope.

Anyway, enough explanation. Here it is, entry 273 in the Third Cambridge Catalog of Radio Sources, 3C 273 itself!

3C 274, the closest quasar to us. Located 2.44 billion light years away in the constellation Virgo.

Kindly hold all applause until the end of the blog post. I know it's not much to look at, but it's remarkable because of what it represents. With a 4-inch telescope and a CCD camera you and I can see the light from the mind-bogglingly intense region of warped space-time around a black hole with more than 800 million times the Sun's mass from over 2,440,000,000 light-years away. It's staggering to me that such a thing is even possible. Hopefully you can see why this is such an amazing picture, even if it isn't as showy as some of the ones I put up here.

3C 273 is an interesting object because it was the first quasar to have its spectrum taken (due to the fact that it is the brightest quasar in the visible light range), which helped show that it wasn't a star and was in fact very much further away than previously thought. Although we know more about quasars now than ever before, they continue to remain mysterious objects and there are many questions about them yet to be answered.


  1. And what's even crazier is that the light you were collecting left that object 2.5 billion years ago, when eukaryotic life hadn't even shown up on Earth, and free oxygen was just appearing in the Earth's atmosphere.

  2. Very nice, sir! Thanks for explaining what a quasar meant. It has been a long time since I first read about it in an encyclopedia when I was five to six years old.

  3. You're welcome! Glad you enjoyed it.


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