Is it possible to locate NEO's or Asteroids with a telescope?

[ak785]

Just a curious question I have ..

Obviously if one is coming from the direction of the sun probably not, but I imagine that with a telescope if you fixed yourself on a particular patch of sky with a webcam and recorded a continuous image you would be able to detect objects of this nature? I imagine you would need a wide field of view?

Anyone know if this is possible, or does anyone do it?

[E621Keith]

It is possible, but probably not with a webcam. The next question is how big a telescope and how close/big/bright the asteroid is.

A lot of people saw and filmed 2012 DA14 last month (unfortunately I was clouded out).

Asteroid is a well known source of false positive for supernova detection.

[ak785]

It is possible, but probably not with a webcam. The next question is how big a telescope and how close/big/bright the asteroid is.

A lot of people saw and filmed 2012 DA14 last month (unfortunately I was clouded out).

Asteroid is a well known source of false positive for supernova detection.

Lets say we took my telescope as an example, something in the region of a 5'' with a GoTo system. I don't know what the average in the astronomy community would be, i'd hazard a guess at around 8'' possibly being the average size?

[breezy]

Blimey how sgl discussions do diversify

[E621Keith]

It depends as much on the asteroid as your scope. DA14 was visible in binoculars during its close approach.

[lukebl]

Just a curious question I have ..

Obviously if one is coming from the direction of the sun probably not, but I imagine that with a telescope if you fixed yourself on a particular patch of sky with a webcam and recorded a continuous image you would be able to detect objects of this nature? I imagine you would need a wide field of view?

Anyone know if this is possible, or does anyone do it?

Are you talking about watching existing ones, or discovering new ones? It's relatively easy to see existing asteroids (including NEOs) with the right sensitive camera (I can capture them down to around 19th magnitude with my setup), but discovering new ones also requires a lot of time and a certain amount of luck. Also, the new ones, of which many are discovered every week, are generally below even 19th magnitude, so a webcam isn't going to get you very far.

[Jim Steele]

I did some asteroid hunting back in my uni days (15yrs ago) using a low power eye piece and black and white 35mm film with an old dslr.

You need to train the scope on the same section of sky over a few days taking a long exposure and look for things that move between days. I'm sure you could do something similar with a more modern setup web camera wise you would probably need some sort of stacking software to simulate a long exposure but I'm a complete novice with modern imaging

[Stargazer_00]

most NEO discovery is done by computers. They can chomp through data captures far quicker than a human can. Essentially you take a photo of the sky and then take another one later. Subtract everything that hasn't moved and then further subtract everything that has moved that you expected to move. What is left is a discovery of something unexpected that moves. You can do this over a period of time to get a feel for the vector the object is moving along which, cross referenced against even more data, should give an indication of the type of object that you have located. It would then get tracked over time along with all the othe tracked moving objects until a decision is made on its vector, its object type and projected path etc and so on.

Obviously this is all based on the images taken at the very start and NEOs typically are very dim. Potentially the dimmest thing in the sky depending on the material, so getting a visible photo isnt always great. Radar seems to work well but has limited range (i believe).

Now obviously you can take photos of the sky with your scope, and you can probably find freeware software to do the graphical computational subtractions and through this method get an independant discovery, but there are many large government funded installations doing this from the best observing spots on the planet every night of the year and have been for many years already. It's a real earth defence force out there