Tag Archives: periodic

872 Comets Supposedly ‘Visible’ — All Telescopically; No Naked-Eye Anymore.

by Anura Guruge


Click to ENLARGE.

My new Excel spreadsheet that enables me to analyze the data.


The raw list from the MPC.
Click to ENLARGE.


I wanted a good handle on this. Yes, the MPC maintains a list, BUT it is hard to analyze. So, I used that data to create one of my SPECIAL Excel spreadsheets. Now I can slice & dice the data at my will.

The MPC list has 872 valid entries! That is a LOT.

C/2020 F3 (NEOWISE) was the brightest — albeit based on a July 13, 2020, reading. Well, that is now way obsolete. The brightness of C/2020 F3 (NEOWISE) is NOW above ‘5’. It has to be ‘5’ or BELOW to be naked-eye visible. So, none of these 872 comets are naked-eye visible.

The next brightest, periodic, 2P/Encke, is at 10. That puts it even beyond binoculars.

So, a heads up. No point looking up. No naked-eye visible comets at present. SMILE.

That is why C/2020 F3 (NEOWISE)  was so special.


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by Anura Guruge


3 New Comets Discovered In August 2020; 2 Periodics & Other With An Extremely High Eccentricity.

by Anura Guruge


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These discoveries have just been confirmed — within the week, i.e., August 2, 2020.

Two, i.e., P/2020 O1 & P/2020 O3, are periodicals — in that they have orbital periods that are less than 200-years. Actually both of these have comparatively short orbital periods, i.e., 4.3 & 10 years. That also means that they don’t go very far from the Sun (or us). Also interesting that both these were discovered right after their most recent perihelions. Their next ones are way out.

Not so with the non-periodic, i.e., C/2020 O2. It is due to perihelion a year from now. Its orbital period has yet to be established. But, note its eccentricity. It is over ‘1’. Anything 1 or over has HIGH eccentricity by definition.


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by Anura Guruge


 

A/2017 U1 — Too Speculative To Claim That It Is ‘Interstellar’.

by Anura Guruge


Click to ENLARGE. From NASA/JPL @ http://www.jpl.nasa.gov.


Click to ENLARGE. Wikipedia: en.wikipedia.org/wiki/A/2017_U1


Definitely extremely interesting and intriguing. Wow. Orbital eccentricity of 1.1922! The greatest we have ever seen — the keywords here being ‘ever seen’. Comet ISON, that crashed and burned on Thanksgiving Day 2013 had an eccentricity of 1.0000015.

But, here is the deal with eccentricity. Anything over 1.0 means that the object will eventually leave our Solar System. That we know. But, what we cannot tell as yet is WHEN A/2017 U1 got that highly eccentric orbit. We just do NOT know — as yet. And maybe never will.

To claim that it must have originated OUTSIDE of our Solar System — is speculative. We do NOT have enough evidence.

NASA/JPL’s official statement confirms that: “So far, everything indicates this is likely an interstellar object, but more data would help to confirm it.” Note the ‘likely‘ and the part about ‘more data … for confirmation‘. That is exactly MY POINT and what I am trying to impress.

The claim that its orbit was NOT influenced by a close encounter with a planet — typically one of the BIG ones — is speculative. It could have been majorly torqued around by Uranus or Neptune. We don’t know.

I have a druthers that this is a very old comet — a periodic one at that, which on its last trip out, maybe 400 years ago got too close to a gas giant and had its orbit turned ‘upside down’.

We don’t know.

All I am stressing is do NOT jump to conclusions.

We know so little about what has happened in OUR Solar System and what is happening right now.

But, it is exciting.


Has a ton of good information about comets.

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by Anura Guruge

2017 Perseids Meteor Shower, Over New England, As Usual Will Peak Around August 11 – 13.

by Anura Guruge


Perseids Meteor Shower over New Hampshire New England


The Perseids Meteor Shower happens each and every year, without fail, in ‘mid-August’. This is because at that time the Earth crosses the path of the repeatedly left behind debris from the periodic comet 109P/Swift-Tuttle — which orbits the Sun with a 133.28 year orbital period. It was discovered in 1862 BUT may have been orbiting the Sun long before that. It was last seen from Earth in 1992. The next time around be in 2126.

It is difficult to predict how good (i.e., spectacular) it will be in a given year. In 2016 they said it would be huge — but it didn’t quite live up to the billing though I did see a few. The weather might not cooperate this year — though it is a bit early to tell. Rain is predicted for August 11, though this could change. There will be some moon BUT that should not be an issue.

109P/Swift-Tuttle has an perihelion distance of 0.96 AU (i.e., just inside Earth’s orbit) and an aphelion of 51.2 AU — which takes it past Pluto.

The name of the Meteor Shower, i.e., Perseids, comes from the constellation Perseus — where the meteors appear to originate. See image above.


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by Anura Guruge

2016 Annual Perseids Meteor Shower, August 11 – 12, Expected To Be BIG — 200/Meteors/Hour.

by Anura Guruge


Perseids on August 12, 2007 from NASA.


Perseids Meteor Shower over New Hampshire New England


The Perseids Meteor Shower happens each and every year, without fail, in ‘mid-August’. This is because at that time the Earth crosses the path of the repeatedly left behind debris from the periodic comet 109P/Swift-Tuttle — which orbits the Sun with a 133.28 year orbital period. It was discovered in 1862 BUT may have been orbiting the Sun long before that. It was last seen from Earth in 1992. The next time around be in 2126.

109P/Swift-Tuttle has an perihelion distance of 0.96 AU (i.e., just inside Earth’s orbit) and an aphelion of 51.2 AU — which takes it past Pluto.

The name of the Meteor Shower, i.e., Perseids, comes from the constellation Perseus — where the meteors appear to originate. See image above.


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by Anura Guruge