Question: If you were to find something in outer-space, what would be done? Such as a unmanned probe sent to the place? Or a further investigation?

Derek McKay-Bukowski answered on 14 Jun 2011:

I really depends on what was seen. Sometimes it would need a space probe (but they can take years to build), sometimes it needs observations… not always from the same telescope.

Here… let me give you a real example that I was involved with.

The used to be an orbiting satellite called “Gamma Ray Observer”. This satellite carried various telescopes, designed to observe gamma rays coming from deep space. On 27 July 1994, it suddenly picked up a strange and unexpected gamma ray signal from the direction of the constellation Scorpius.

The astronomers working with the Gamma Ray Observer satellite contacted a few other observatories around the world and explained what they had seen and where it was. Some of the other telescopes then started to scan that part of the sky looking to see if they too could detect anything.

On 12 August 1994, an old radio telescope in Australia picked up a new radio signal coming from the exact same direction. So, this new object gives off radio waves too?

So, the astronomers at that old telescope thought that the best thing to do would be to get lots of radio telescopes watching it. Because there was a definite signal, this called for the best instruments available!

At the time I was working in the control room of one of these big radio telescopes. My telescope had not 1, but 6 large dishes. I got the phone call, followed by some e-mails and I halted the current tasks that the telescope was doing and swung the big dishes around to check out this new radio signal.

Together with various other telescopes, we observed it for a few weeks until it faded away. However, there was something not right. If our distance calculations were correct, it would appear that this new object was travelling faster than the speed of light! Surely this was impossible?

That required more investigations, so I contacted some theoretical physicists and asked them to help try and explain this unusual object.

In the end, we figured it out. It was being caused by a strange relativistic projection effect (called superluminal motion). That allowed us to work out that the object in question was probably a Microquasar. We put out a press-release, wrote up an article for a scientific journal and gave radio and television interviews.

It was a very exciting event!

Since then many other telescopes have studied this strange object… known by its catalogue number as GRO J1655-40.