As far as the longest period comets go, the current leaders are Comet Hyakutake with an orbital period of 70,000 years, Comet C/2006 P1 with an orbital period of about 92,000 years and Comet West with an orbital period of about 250,000 years. Of course, we see new comets regularly so a new leader may well emerge in the near future.
Comets can have short periods of up to 200 years (such a Halley’s Comet with a period of 76 years) or long periods of between 200 to potentially millions of years.
Ideally, to know the period of a comet you would need to observe it twice and measure the time between observations to ascertain its period. However while comets have been observed for thousands of years it is very difficult to state with certainty whether a long period comet observed today could be one we have seen before.
Consequently scientists have to map the trajectory of a comet and extend it to estimate its period. This process is by no means accurate as interactions with other Solar System bodies and loss of mass due to evaporation of volatile materials can all alter the orbital properties of comets.
Using a telescope at the top of Mauna Kea, Hawaii, scientists have discovered a new dwarf planet in our solar system, a body about 435 miles across that lacks a name and that researchers still know little about.
The new dwarf planet, dubbed 2015 RR245, has such a huge, highly elliptical orbit that it takes an astonishing 700 Earth years to complete one trip around the sun, and it ventures over 120 times further away from the sun than our planet does.
But ya, there’s nothing left to discover about our own solar system much less what lies beyond that might only occasionally come by on a scale of 10’s, 100’s, thousands or millions of years.
There was no validation of the method they used to adjust the data. In other words, the methods purportedly changed the raw data to values that the “researchers” considered to be correct. But I did not see evidence that they proved their methods produced more accurate data.
Physics is the same no matter the size but when the masses involved are tiny and the distances large then the size of the force drops to the point of being nearly negligible.
I still don’t know why you think this is relevant given none of these particles (maybe boulders) is going to affect the earth’s orbit one iota.
An object 1-3 km isn’t going to do anything to our orbit.
This article points out exactly why this is unlikely to be the case. Anything crossing our orbit from far away also crosses the orbit of the gas giants. Eventually it’s going to be captured by Jupiter as these moons have or ejected from the solar system. It’s a good thing too because otherwise our planet would have a much higher frequency of life threatening asteroid impacts (from large objects, not 200 meter chunks of rock which you’ve stopped trying to peddle as able to kill most of life on the planet).
It used to be much less stable but the last few billions years cleaned out the stellar debris.
And I’m not “ignoring” billions of years. It’s just not relevant to the topic of discussion, the Quaternary ice age that has only been going on a few million years.
That’s basically nonsense. If an object is in orbit around the sun, it’s speed will be the same as it crosses Earth’s orbit. It will be accelerating as it approaches the sun and decelerating as it gets farther away, but the speed (and therefore the momentum) will be the same.
A diversion, however, because we aren’t really discussing impacts.
Still waiting for any substantiation about this serious speculation that they come into the inner planets. It wasn’t in the Times article. The two objects mentioned come no closer than 76 AU to the sun.
Well, if the one urban heat island weather station is surrounded orthogonally by four rural weather stations and tour goal was to get rid of the heat island effect, it would be reasonable to replace the urban with the average of the four rural.