First off,
here is the table I created over the last weeks, which will be the basis of what follows. Feel free to play around with it as you wish.
Data, Questions and graphs that can be gathered from this table will follow soon.
First off, you can find the short version of what follows
here and in the main table (already mentioned) out of which all of it is derived
here. You can adjust the tables and graphs as you like, nothing will happen since I've secured that only I can edit it.
- From the table we can see a total of 566 NEO objects that were ever discovered that have and will reach the earth closer than the moon. We can also see that the first object of this kind was only discovered in 1991 (1991 BA) via the "Date Discovered" column! The earlier dates are calculated approaches of the objects that must have happened in the past (aka. before 1991).
- Out of those 566 NEO objects 548 close encounters have already happened, the rest (48), will happen in the future. So there is a total of 596 close encounters listed in the table, including the future. The close encounters till present (548), excluding the future approaches, happened in this sequence:
Notice that the numbers started to pick up out of the norm (reaching back to 1910) exponentially around 2003 until it ended up orders of magnitude higher in the last four years, while 2018 and 2019 (which hasn't ended yet) are the highest of them all. Now compare this overall trend with the fireball data and other data points. A very close match! Also notice the dips in 2012, 2013 and 2015 respectively! Here again we can ask, how can that be explained by "improved technology"? Also notice the missing years in which no close encounter as far as we know happened.
We can also summarize that 500 out of those 548 close encounters happened since 2003 till present. Or in other words; over 91% of those close encounters happened since 2003.
- In the following graph we can see a sequence comprising the same 548 close encounters, ordered by the date of discovery (first observation) of those objects. Remember the first of those objects was only discovered in 1991 (1991 BA):
A very similar picture... Also notice the dips again and compare them with the dips in the fireball data. So we can summarize that 542 out of those 548 close encounters were discovered since 2002. Or in other words; Almost 99% of those close encounters were discovered since 2002. Also notice that in the 11 years from 1991 to 2001, a sum of only 6 such objects were discovered, while there are 6 years in that time frame where a total of 0 were discovered (1992, 1995, 1996, 1997, 1999, 2000)!
We can then also ask why in those years (1992, 1995, 1996, 1997, 1999, 2000) not one single telescope on earth discovered even one such object, although they are usually pretty close to earth and thus theoretically better to spot? Was the technology back then really so much worse? Were there no telescopes looking at the sky all around earth? I think the far more likely and logical reason is because the space around earth was far less crowded with objects back then.
Also, we can summarize now; in the whole history of mankind up to 1991, not one single object of that kind was ever discovered (ZERO!). Or in other words: In all the years into, through and out of the age of reason, through the industrial revolution, in and out of WWI and WWII, deep into and out of the cold war and deep into the space age, a sum of
ZERO such objects were ever discovered up until the year 1991! Now, compare this to last year, in which a staggering number of 78 such objects were discovered in just that single year! How likely is this due to "bad technology back tan", especially if you compare it with the orders in magnitude of increase starting in 2002? It is just such a staggering discrepancy (especially if you compare it with similar data from other areas) that I think the likelihood that this is just caused by "improved technology" is pretty slim in comparison with the simple idea that immediate environment around earth has gotten much more crowded with objects.
There is a further reason I say
immediate environment around earth (besides the fact that we are only looking at objects in this inquiry that have come and will come closer to us than the moon). If we look at the table, we discover something else quite interesting (also in terms of the idea "bad technology back then" and "improved technology now).
- Again we use the 548 close approaches till present as basis. Out of those 548 close approaches. 330 were discovered after they already passed closest to earth, or on the same day as the close approach happened. Which means that over 60% of those (548) close encounters were discovered after their closest approach to earth. So we can ask; Were the telescopes before 1991 and after 1991 so bad that they couldn't discover those 330 encounters that happened so close to earth (and thus argumentatively easier to spot) at the time of their closest approach?
Further, an additional number of 140 out of the total of 548 close encounters were spotted just 1 to 2 days before their close approach. That makes 25.5% out of those 548 encounters. Then we have a flopping number of 68 out of those 548 encounters that were spotted a max amount of 13 days prior (out of which 53 close encounters (or almost 78% ) were spotted just 3 - 5 days prior) or 12.4% out of the total of 548 encounters.
So that leaves us with a number of (330 + 140 + 68=) 538 close encounters out of the total of 548 that were discovered either much, much later than their close approach, or at most, 13 days prior to their close approach, which is a staggering number of over 98%. The flopping remaining number of 10 close encounters (under 2%) were spotted between 192 days and 3649 days prior to their close approach. Of those 10, the biggest object was a max estimated diameter of 250 Meters, while another 2 objects out of those 10 were a max estimated diameter between 94 meters and 110 meters; the remaining 7 of those close encounters were a max estimated diameter between 7.5 meters and 43 meters. While one of those smaller ones (max. diameter of 18 Meters) was discovered the max amount of 3649 days (in that 548 encounter list) prior, as opposed to the biggest one out of those 10 (max. diameter of 250 Meters) that was discovered much later; 2141 days prior.
So we can summarize: The 538 close encounters on record, that were discovered either much, much later as their close approach, or a maximum of 13 days before the fact (aka. almost ZERO forewarning or almost ZERO observation prior), include the biggest object (2011 MD5), the third biggest object (2002 CU11) and the fifth biggest object (1998 KJ1)) in the whole list, with a max estimated diameter of "1600 meters", "1200 meters" and "780 Meters" respectively. Since those three apparently slipped by earth in their close encounter in the years "1918" , "1925" and "1914" respectively, we can indeed argue that that could have been due to "bad technology".
- However, since the year 1991 we have experienced a total number of 511 close encounters with the following size distributions, sorted chronologically since the first observation of such objects in 1991:
Here you can find the whole graph expanded to see each diameter better. Notice that huge chucks flew by earth all throughout that period (notice also the peak ones) and how a whole number of those were discovered literally in a whole series of successions in 2017, 2018 and 2019. However, the last graph above is a bit misleading IMO to get to know if there is an increase both in sizes and numbers.
The reason for that is for example that in 2001
only a total two objects flew by earth that close, namely (2001 BA16), with an estimated max diameter of 38 meters, and (2017 VW13) with an estimated max diameter of 430 meters, compared with 2018 for example, in which a total of 78 such objects flew by earth. This means that the year 2001 stands out in the last graph above by the fact alone that only two objects were discovered, while 2018 doesn't stand out because 78 such objects were discovered. Or in other words; in the last graph above the number of discoveries as well as the sizes of those objects are not accounted for in determining an increase or decrease because both variables are not correlated with each other.
There is however a better (and more trustworthy) way IMO to include both variables in the equation in order to show a more realistic trend both in terms of sizes and numbers. For that I've totaled up all max estimated object sizes for each year (not mathematically all that correct, I know. Mass would be better, but we don't have that), to arrive at a hypothetical "total diameter" for each year, with the following result for the exact same time period seen in the last graph above:
That means that the total diameter (or rather, total volume or mass of all object combined in each year) also increased in a similar exponential fashion since 1991.
One last note for now, for a better perspective: In 2017 we have seen for example a total of 5 close encounters over 40 meters in size with max estimated diameters between 41 meters and 82 meters. In 2018 we have seen a total of 6 close encounters over 40 meters in size, 3 of which had max estimated diameters between 41 meters and 62 meters, 2 of which had max estimated diameters between 100 meters and 110 meters and 1 of which had a max estimated diameter of 190 meters. So far in 2019 we have seen a total of 5 close encounters over 40 meters in size, 3 of which had max estimated diameters between 41 meters and 66 meters, while the other 2 close encounters had max estimated diameters between 120 meters and 130 meters.
Out of those 16 objects mentioned in the last paragraph above (over 40 meters in size between 2017 and 2019), only 1 was discovered far ahead of time, namely a 110m object that was spotted 2723 days earlier. While 1 of those objects (41 Meters in size) was discovered 13 days prior; 1 of those objects (62 Meters in size) was discovered 6 days prior; 2 of those objects (66 and 120 Meters in size respectively) wer discovered 3 days prior; 2 of those objects (100 and 130 Meters in size respectively) wer discovered 1 day prior, while the remaining 9 objects were all discovered after they already made their close approach, in the following sequenze: 1 day to late (45m), 2 days to late (41m), 2 days to late (75m), 2 days to late (82m), 2 days to late (190m), 4 days to late (41m), 4 days to late (49m), 6 days to late (57m), 546 days to late (61m).
You can find all the graphs above in more detail
here as well as the main table from which all of this is derived
here. There is a lot more interesting data that can be pulled out. For example, we haven't even mentioned the future encounters or how the past ones might relate to happenings on earth.
en.wikipedia.org
spacetelescopelive.org
