Posted on 10/21/2017 2:32:42 PM PDT by BenLurkin
[P]revious estimates of the remaining NEAs have been plagued by a consequential round-off error that have skewed the results.
The source of this error has to do with... “size-frequency distribution”.
...
2015 study conducted by Harris and D’Abramo – which appeared in Icarus under the title “The population of near-Earth asteroids” – yielded an estimate of 990 NEAs that were larger than 1 km in diameter. However, Tricario’s study (“The near-Earth asteroid population from two decades of observations“, also published in Icarus), which was based on the opposite “less than or equal to” assumption, produced estimates that were 10% lower.
As Harris explained, this prompted D’Adramo and him to considered a different approach. “We corrected the problem for the current analysis by choosing bin boundaries at .05 magnitudes, e.g. 17.25 to 17.75, so the 0.1 round-off thresholds naturally put objects in the right bin,” he said. “When Tricarico and I each made these corrections, our population estimates fell into almost perfect agreement.”
After applying the correction, Harris and D’Abramo’s overall estimate of undiscovered NEAs dropped from 990 to 921 ± 20. Beyond allowing for consistency between different studies, these corrected estimates also reduced the total number of undiscovered objects that remain undiscovered. According to the latest tallies from NASA’s Jet Propulsion Laboratory, 884 NEAs that are about 1 km in diameter have been discovered so far.
Based on the previous population estimate of 990 objects, this implied that the current surveys are 89% complete and 106 were yet to be found. When the corrections were applied to these numbers, JPL’s surveys now appears to be 96% complete, and only 37 objects remain to be found (almost three times less). Naturally, these new estimates depends on their own sets of assumptions, and different results can be obtained based on different criteria.
(Excerpt) Read more at universetoday.com ...
Crap. Now the Algore Loser crowd will go back to pimping “global warming” harder than ever.
A. It only takes one.
B. There are likely plenty of unknown unknown classes.
C. See A.
There is a relation between frequency and size.
As Ted Danson put it, “It was like throwing a
hot dog down a hallway.”
It’s like a I used to tell my kids. A scientific pronouncement is only valid until the next scientific pronouncement on the same subject comes a long.
Did he say that when he was dating Whoopi?
But then it only takes one.
“reduced the total number of undiscovered objects that remain undiscovered.
How does one do that? Reduce the estimate perhaps.
Bingo.
If they’re unknown, then how do we know there are fewer?
Did the global warming kill them or did they run away from the threat of EMP?
Did the global warming kill them or did they run away from the threat of EMP?
I can now sleep more soundly.
Absence of evidence is not evidence of absence.
Good point.
Without evidence of existence there’s no reason to suppose something exists.
How does one do that?
_____________________________________________
Absence of evidence is evidence of absence?
I mean, if we don’t know they’re there, they can’t exist, right?
Yep, just like those Kraut tanks that keep busting out of the Ardennes when everyone says there is no evidence of anything unusual in there.
The good news is that there are fewer asteroids.
The bad news is that that’s because the Zycathian Invasion Fleet blasted most of them to clear a path to earth.
Back in the day, that did happen often enough to be considered a predictable pattern.
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