27 May '15 13:14>
Originally posted by whodeyNobody in the press reporting on the biggest story in history??? Not a chance.
So what if an amateur sees something and reports it and no one in the press tells about it?
If such a catastrophic event were to happen on earth, there would be virtually nothing that could be done about it.
Why then create hysteria?
However, as I made clear [I thought] in my last post, you don't just look at an asteroid or comet
and instantly magically know it's orbit.
It takes many observations over at least several days, usually weeks or months, to get
any kind of accurate orbit. [with the most accuracy coming from radar ping's]
As your telescope is on a rotating planet [with weather], you need to tell other astronomers around
the world about the asteroid so that they can take part in tracking it.
So, in the event of the discovery of a new asteroid or comet that is on a collision course, at
first, nobody knows that it is on a collision course.
The sequences goes something like this.
Astronomers [professional or otherwise] discover a new asteroid/comet.
They report it's location in the sky to the Minor Planet Centre [hoping that it's a new discovery that
will be named after them, because it's cool to have an asteroid named after you] who issue an
notice telling other astronomers [and the public] that this object exists and where to find it.
Follow-up observations are made which give a rough indication of the objects orbit.
Calculations show that there is a very small probability of this object hitting the Earth on either this,
or some near future orbit.
If this asteroid or comet has any significant size, this will cause it to have a high Torino Scale rating.
http://en.wikipedia.org/wiki/Torino_scale
http://neo.jpl.nasa.gov/torino_scale.html
Which is reported publicly. [and this happens and occasionally even hits the news]
This acts as a signal for more serious telescopes to home in on the object and do further follow-up observations
to further refine the objects orbit.
As further refinements are made and the projected orbit is calculated more accurately then the
risk assessment will be [publicly] updated.
It's quite usual in such instances for the likely impact probability to go up before going down.
In the case we are discussing where a large object IS actually on a collision course, the probability will
only go up.
However, there is no cover-up option available at this point. The asteroid/comet is already front page
headline news, it's location known to everyone, and visible in any decent telescope by anyone in the
world.
Thousands of astronomers in countries all over the world can check and verify the orbit and observations,
along with thousands more amateurs.
The worlds leaders will want and need to divert whatever resources available to deal with this threat.
Also near impossible to do secretly, and it's beneficial to get all available input and assistance which
means this needs to be public.
We CAN divert asteroids and comets, given enough warning. Which is why these programs exist.
In the case where an object is spotted without much warning [1~2 years or less] then far from
wanting to keep information secret, you want to make it publicly known so that the orbit is pinned
down as fast as possible so that you know it's a threat as fast as possible to give the maximum amount
of time to deal with it.
2.5 km comet would be a catastrophe if it hit.
Its not big enough to make us go extinct however.
The asteroid that wiped out the dinosaurs, which was likely 3~8 times denser, and was > ~8km across.
That's > ~30 to ~80 times as massive. [> ~10 to ~40 times as energetic factoring in velocity]
And we can take steps to mitigate the damage with advanced warning.
Keeping such an event secret, would be stupid, irrational, counter productive, and almost totally impossible.
Given that the prior probability of such an impact in our lifetimes is minuscule, coupled with the minuscule
probability of successfully achieving a cover up in such an event, coupled with the low desirability of such
a cover-up, makes the probability that such an event and cover-up will occur in our lifetimes is too tiny to
consider remotely plausible.
The frequency of internet rumour conspiracy freakouts on this subject however is several per year.
This is a conspiracy nut freakout, nothing more.