2004 MN4 impact risk (Torino scale 2 risk)

Bouncing around various mailing lists is news that
the asteroid 2004 MN4 has been rated at a Torino
scale impact risk of 2, the first object to ever
garner that rating. The Palermo scale risk is 0.39
(a positive number is highly threatening). The current
best guess probability of impact in the first risk
year, 2029, is 0.43% (4.3E-3) of impact on April 13 2029,
with probabilities in the E-6 range or lower around
April 13 of 20-odd further years between 2029 and 2079.

http://neo.jpl.nasa.gov/risk/2004mn4.html
http://neo.jpl.nasa.gov/risk

The object is estimated at 420 meters diameter and
a impact energy if it hits in any of these encounters
is estimated at 188,000 megatons equivalent.

Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.


-george william herbert

George William Herbert wrote:

http://neo.jpl.nasa.gov/risk/2004mn4.html
http://neo.jpl.nasa.gov/risk

The object is estimated at 420 meters diameter and
a impact energy if it hits in any of these encounters
is estimated at 188,000 megatons equivalent.

The web page says 1,900 megatons.

Paul

Paul F. Dietz wrote:
George William Herbert wrote:
http://neo.jpl.nasa.gov/risk/2004mn4.html
http://neo.jpl.nasa.gov/risk

The object is estimated at 420 meters diameter and
a impact energy if it hits in any of these encounters
is estimated at 188,000 megatons equivalent.

The web page says 1,900 megatons.

I sit corrected. I checked the webpage but apparently
transcribed badly.

Still a major regional catastrophe; without advanced modeling,
in rough terms, a 250 kilometer circle of residential structures
knocked down, a 150 km circle of nearly all structures knocked
down, etc etc.


-george william herbert

To add insult to injury,

April 2029
S M Tu W Th F S
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30


-george william herbert

"George William Herbert" wrote in message
...

Still a major regional catastrophe; without advanced modeling,
in rough terms, a 250 kilometer circle of residential structures
knocked down, a 150 km circle of nearly all structures knocked
down, etc etc.

And if it crashes into the sea, it could be even worse (?)

--
Alan Erskine
We can get people to the Moon in five years,
not the fifteen GWB proposes.
Give NASA a real challenge

George William Herbert wrote:

Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.


Wouldn't it be easier and cheaper to just wait until it gets here, then
reach out and stick in the transponder as it passes by?

--
Reed Snellenberger
GPG KeyID: 5A978843
rsnellenberger-at-houston.rr.com

On 24 Dec 2004 04:05:42 GMT, (George William
Herbert) wrote:


Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.

RTG-powered, probably. If 2004 MN4 is tumbling, the transponder could
die before the solar panels get enough sunlight to keep it alive.

Brian

On Fri, 24 Dec 2004 04:50:56 GMT, Reed Snellenberger
wrote:

George William Herbert wrote:

Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.


Wouldn't it be easier and cheaper to just wait until it gets here, then
reach out and stick in the transponder as it passes by?

Reminds me of the back-cover write up for "Lucifer's Hammer"...

"The odds of the comet hitting were 1 in 10,000.
Then 1 in 1,000.
Then 1 in 100.
Then..."

Brian

Brian Thorn wrote:
(George William Herbert) wrote:
Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.

RTG-powered, probably. If 2004 MN4 is tumbling, the transponder could
die before the solar panels get enough sunlight to keep it alive.

It should be possible to place it in surface locations
that reliably get fairly consistent sun exposure.
The batteries to survive the dark periods are
a well known design issue.


-george william herbert

George William Herbert wrote:
Bouncing around various mailing lists is news that
the asteroid 2004 MN4 has been rated at a Torino
scale impact risk of 2, the first object to ever
garner that rating. [...]

Let me be the first of many to suggest that a mission
to stick a solar powered radio transponder on 2004 MN4
should now percolate up to the top of the NASA unmanned
science mission priorities list, so that we can try
and nail down its orbit significantly better.


This idea is a waste of money. For a fraction of the cost of the most
simple space mission, you can build a big transmitter on Earth, capable
of radar observations of all interesting asteroids. This could measure
the orbits of *all* near Earth asteroids, not just one, for much less
money. The accuracy is just as good for all practical purposes
(unknowns like the solar reflecticity of each asteroid dominate the
long tern error budget, not the error terms in individual
measurements). Finally, all the high tech pieces are here on Earth
where they can be repaired and improved easily.

I've written a paper on a particularly cheap way to do this (
http://www.lscheffer.com/transmitter.pdf ) but you can also do it the
old fashioned way with a big dish and strong transmitter, and it would
still be cheaper than any space probe. Heck, you could probably build
an entire duplicate Arecibo for the cost of even a small asteroid
mission. (The Green Bank telescope, a bleeding edge 100 meter dish
with a computer deflectable surface, was about $100M.)

I'm all for more studies of near Earth asteroids, but we need to put
the money where it's most effective, even it this is not as glamourous
as space probes.

Lou Scheffer