Episode 37: Gravitational Lensing

[Fraser]

Astronomers are always trying to get their hands on bigger and more powerful telescopes. But the most powerful telescopes in the Universe are completely natural, and the size of a galaxy cluster. When you use the gravity of a galaxy as a lens, you can peer right back to the edges of the observable Universe.

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[Himanshu Raj]

Hi Frazer!

It was a very fascinating show on one of my favourite topics.

Can Gravitational Lensing help us look all the way back to the time just after the Dark Ages? Also are the multiple Gravitational Lensing effects seen yet.

[rogerg_au]

Gravitational Lensing is something I've been interested in for a while so it was great listening to a Astronomy Cast episode on the topic.

I spend much of my time as an amateur astronomer taking long exposures of faint galaxy clusters, just for the fun of it, to see what I can see, see how many galaxies I can identify, see what is out there in the distant universe, etc.

In one image I captured a galaxy which to my eye looks like it is lensed. I have no scientific backing to the thought at all - it just looks odd while all other galaxies in the FOV appear normal. It is curved like a banana, like it is curved around a point in space.

Does anyone know if there is a catalogue of known lensed objects or the like that I could search for this galaxy?

The galaxy in question is PGC 96819 and the image in question is here (click image to see larger):
http://www.rogergroom.com/rogergroom...m.jsp?Item=284

Thanks,
Roger.

[Terry Gush]

We see plenty of great examples of Gravitational Lensing at optical wavelengths such as Einstein Rings.

How about other wavelengths? Are there any ultra-violet or X-Ray Einstein Rings ?