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Never-before-seen colossal comet on a trek toward the sun

Jun 1, 2020
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This is important because it comes from the enigmatic Oort Cloud.

Its aphelion seems to be about 31k AU, which is about midway into the proposed Oort Cloud.

[One site said its aphelion was at about 20k AU, but the following NASA link shows the 31k.]

JPL Small-Body Database Browser (nasa.gov)

This matches the articles total period time of about 5-1/2 million years (2.5 million to reach us).

Also of interest is its inclination. It is tilted 95 degrees to our ecliptic plane, so I think this means it is coming from below and swinging almost perpendicular to our plane with the Sun.

Perhaps someday we will be able to get some idea as to the typical size of objects out there. The are supposed to relatively small since it takes unusual dynamics for the planets to throw massive planet-like objects a long way. In this case, it was tossed about 4-1/2 trillion km. Even Nolan Ryan couldn't do that. ;)
 

rod

Oct 22, 2019
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FYI, do not get too excited here about the Oort cloud :)

The orbit and period is apparently difficult to nail down. Note this report, Space object with orbit stretching into the Oort cloud discovered, https://phys.org/news/2021-06-space-orbit-oort-cloud.html The period is said to be 612,190 years. "One trip around the sun has been calculated to take 612,190 years. It is currently moving deeper into the solar system, which means astronomers will have an opportunity to observe it 10 years from now."

My observation. Wikipedia reports on this object. https://en.wikipedia.org/wiki/2014_UN271 Wikipedia reports aphelion distance 40,000 au inbound, 55,000 au outbound. Perihelion distance 10.95 au. Semi-major axis inbound = 20,000 au, outbound = 27,000 au, e = 0.99945 inbound, 0.9996 outbound. Orbital period or P = 3 million years inbound, 4.5 million years outbound. Apparent magnitude mv + 21.2. Compare the orbital period in wikipedia to the phys.org report, 612,190 years. Using Jean Meeus Astronomical Alogrithms, I used a = 24,000 au, e = 0.9996, aphelion = 47,990 au, perihelion = 9.6 au, mass of object = 6 x 10^17 g cm^-3. Orbital period = 3.7183 x 10^6 years and in a period of 1 billion years could complete 269 revolutions around the Sun, using 612,190 year period, even more perihelion passages are needed. Whether the comet/object has completed multiple perihelion passages or aphelion passages is another story.

 
Jun 1, 2020
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BTW, there
The orbit and period is apparently difficult to nail down. Note this report, Space object with orbit stretching into the Oort cloud discovered, https://phys.org/news/2021-06-space-orbit-oort-cloud.html The period is said to be 612,190 years. "One trip around the sun has been calculated to take 612,190 years. It is currently moving deeper into the solar system, which means astronomers will have an opportunity to observe it 10 years from now."
That period seems way off, but time will tell with many more observations. That figure is the P value from the Minor Planet report, so do we know that P is the period ( I found no reference guide)? I would assume so, but perhaps not.

The other link given is from NASA, which is my source that matches this article (5.5 million year period), so it may have begun its run toward the Sun about 2-1/4 million years ago. But, that long ago, IIRC, there was a close approach by one or more stars. [I'll have to dig up that work.] So, perhaps a close approach gave it a push, thus it may have begun its run much earlier. If this is somehow true, not that it is, we may see more visitors than average in the future.
 
Jun 1, 2020
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Kepler's laws do a super job of making the number crunching easy. Cube 'a', then take the square root to get the period. Free-fall time is about 1/2 the period.
 

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