[meteorite-list] Space Radar?

From: Richard Kowalski <damoclid_at_meteoritecentral.com>
Date: Thu, 14 Apr 2011 16:28:26 -0700 (PDT)
Message-ID: <511283.91039.qm_at_web113614.mail.gq1.yahoo.com>

Hi Eric,

Sorry but I'll have to be a bit blunt here.
Amateurs can NOT do what is required. A decade ago it was possible for amateurs to discover main belt asteroids with typical backyard telescopes. That golden age is long gone. To just keep up with the current state of the field, an observatory needs to be able to detect moving objects fainter than 20.0V magnitude with just a minute or two exposure time.

Most of the telescopes involved in the NEO survey effort today have apertures of at least 1 meter. The professional telescopes smaller than this are being excluded because they can't detect these faint NEOs were now discovering. I don't know too many amateurs who have optically "fast" 1-m telescopes in their backyard.

To detect and track these smaller NEOs, the amount of light gathering power will need to increase. How many amateurs have 2-m class telescopes in their backyards?

There is plenty for amateurs to do in the field of asteroid research, but discovery, even of main belters, is not one of them. Detecting NEOs is big science and it has a big price tag. There is no real way to fudge this.

For those interested, I'd suggest you read the National Research Council's:

_Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies_

It can be downloaded here:

http://www.nap.edu/catalog/12842.html

This National Academy of Sciences report to NASA & Congress discusses exactly what would be needed to detect and follow objects down to 140-m (starting from where we are now).

I've mentioned why radar is not a good option for this. Rob Matson commented on the Inverse Square Law, which alone effectively eliminates radar from being a useful technology for this task.

An extremely important point that for some reason always gets forgotten or ignored is that we are NOT looking for impactors just before they hit. We want to find them years, decades or most preferably, centuries before an impact. While objects like 2008 TC3 are of very great interest to those on this list, again bluntly, there is effectively ZERO interest in a concerted effort in finding these objects before they hit, and certainly exactly zero dollars available to build a program to do this.

Now obviously we continue to detect these small objects and there is scientific interest in finding more TC3s. We at CSS are looking into ways to increase our ability to detect the small "meteorite droppers", but we are mandated by our funding source, the US Congress through NASA to discover large, potentially damaging NEOs. Nothing we do to increase the discovery rate of these small objects are allowed to compromise our mandated efforts.

To go from 1km to 140-m objects requires at least 4x more funding for the infrastructure and operations than the current efforts.

To go down to 50-m would probably require 10x the funding the 140-m effort would cost, maybe $10,000,000,000, or about Gigabuck per year

Getting down to TC3 sized objects, maybe another 10x that. 10 billion dollars a year is unlikely considering the entire NEO budget today is only around 6 million dollars per year.

Of course if your desire is to go out and find meteorites after the fact, a widespread network of fireball cameras is much less expensive and much more efficient for that purpose.

Cheers

--
Richard Kowalski
Full Moon Photography
IMCA #1081

Received on Thu 14 Apr 2011 07:28:26 PM PDT