One more key requirement agreed upon in 2006 was that a planet must have enough mass to sweep its orbital path clear of all other objects, and Pluto doesn't live up to this. There already known Kuiper Belt objects larger than Pluto, so should school children memorize ten, eleven, or even more, planets? And is minor planet such a bad designation? -----Original Message-----
Date: Mon, 20 Jul 2015 21:01:52 +0000 (UTC) From: Joe Bauman <josephmbauman@yahoo.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Subject: Re: [Utah-astronomy] Pluto Planet Status Message-ID: <634580063.1148653.1437426112126.JavaMail.yahoo@mail.yahoo.com> Content-Type: text/plain; charset=UTF-8
A much stronger argument about it is that Pluto may be a great deal like other Kuiper Belt objects, and we can't have dozens of small objects identified as planets.
From: "baxman2@q.com" <baxman2@q.com> To: utah-astronomy@mailman.xmission.com Sent: Monday, July 20, 2015 12:58 PM Subject: [Utah-astronomy] Pluto Planet Status
I would personally favor Pluto being returned to official Planet status for the following reasons. It is spherical, has five months, and surface geological activity. The only argument against it, is Pluto's size being smaller than Earth's Moon, making it somewhat comparable to a number of known minor planets.
Hi John, You and Chuck have mentioned that Pluto doesn't pass the "cleared path" part of the IAU planet definition. Several astronomers have mentioned that this is a rather sloppy part of the definition. For example, several planets including earth and Jupiter have Trojan asteroids which trail and/or lead the planet by 60 degrees in the same orbit as a planet. Also, given the current error bars - Pluto is back to being larger than any of the other known Kuiper belt objects - including Eris. Like Chuck, I really don't have a dog in this fight - but I think that the IAU definition was poorly constructed and was created with the express desire of removing Pluto from the major planet category. Clear skies, Dale. On Tue, Jul 21, 2015 at 8:26 AM, John R. Peterson <docpity@earthlink.net> wrote:
One more key requirement agreed upon in 2006 was that a planet must have enough mass to sweep its orbital path clear of all other objects, and Pluto doesn't live up to this. There already known Kuiper Belt objects larger than Pluto, so should school children memorize ten, eleven, or even more, planets? And is minor planet such a bad designation?
-----Original Message-----
Date: Mon, 20 Jul 2015 21:01:52 +0000 (UTC) From: Joe Bauman <josephmbauman@yahoo.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Subject: Re: [Utah-astronomy] Pluto Planet Status Message-ID: <634580063.1148653.1437426112126.JavaMail.yahoo@mail.yahoo.com> Content-Type: text/plain; charset=UTF-8
A much stronger argument about it is that Pluto may be a great deal like other Kuiper Belt objects, and we can't have dozens of small objects identified as planets.
From: "baxman2@q.com" <baxman2@q.com> To: utah-astronomy@mailman.xmission.com Sent: Monday, July 20, 2015 12:58 PM Subject: [Utah-astronomy] Pluto Planet Status
I would personally favor Pluto being returned to official Planet status for the following reasons. It is spherical, has five months, and surface geological activity. The only argument against it, is Pluto's size being smaller than Earth's Moon, making it somewhat comparable to a number of known minor planets.
_______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Send messages to the list to Utah-Astronomy@mailman.xmission.com
The Utah-Astronomy mailing list is not affiliated with any astronomy club.
To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".
There is actually a good paper that defines clearing the orbital neighbourhood. This paper talk about object at the Lagrange points. Were as the paper was written by Alan Stern (Principle Investigator on the New Horizons project) I give it a fair amount of credit. The distinction is that objects at the Legrange points are controlled by the gravitational force of the major object. http://www.boulder.swri.edu/~hal/PDF/planet_def.pdf On Tue, Jul 21, 2015 at 9:47 AM, Dale Hooper <dchooper5@gmail.com> wrote:
Hi John,
You and Chuck have mentioned that Pluto doesn't pass the "cleared path" part of the IAU planet definition. Several astronomers have mentioned that this is a rather sloppy part of the definition. For example, several planets including earth and Jupiter have Trojan asteroids which trail and/or lead the planet by 60 degrees in the same orbit as a planet.
Also, given the current error bars - Pluto is back to being larger than any of the other known Kuiper belt objects - including Eris.
Like Chuck, I really don't have a dog in this fight - but I think that the IAU definition was poorly constructed and was created with the express desire of removing Pluto from the major planet category.
Clear skies, Dale.
On Tue, Jul 21, 2015 at 8:26 AM, John R. Peterson <docpity@earthlink.net> wrote:
One more key requirement agreed upon in 2006 was that a planet must have enough mass to sweep its orbital path clear of all other objects, and Pluto doesn't live up to this. There already known Kuiper Belt objects larger than Pluto, so should school children memorize ten, eleven, or even more, planets? And is minor planet such a bad designation?
-----Original Message-----
Date: Mon, 20 Jul 2015 21:01:52 +0000 (UTC) From: Joe Bauman <josephmbauman@yahoo.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Subject: Re: [Utah-astronomy] Pluto Planet Status Message-ID: <634580063.1148653.1437426112126.JavaMail.yahoo@mail.yahoo.com> Content-Type: text/plain; charset=UTF-8
A much stronger argument about it is that Pluto may be a great deal like other Kuiper Belt objects, and we can't have dozens of small objects identified as planets.
From: "baxman2@q.com" <baxman2@q.com> To: utah-astronomy@mailman.xmission.com Sent: Monday, July 20, 2015 12:58 PM Subject: [Utah-astronomy] Pluto Planet Status
I would personally favor Pluto being returned to official Planet status for the following reasons. It is spherical, has five months, and surface geological activity. The only argument against it, is Pluto's size being smaller than Earth's Moon, making it somewhat comparable to a number of known minor planets.
_______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Send messages to the list to Utah-Astronomy@mailman.xmission.com
The Utah-Astronomy mailing list is not affiliated with any astronomy club.
To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".
_______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Send messages to the list to Utah-Astronomy@mailman.xmission.com
The Utah-Astronomy mailing list is not affiliated with any astronomy club.
To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".
http://solarsystem.nasa.gov/planets/profile.cfm?Object=Dwarf&Display=Sats Sent from my iPad
On Jul 21, 2015, at 9:47 AM, Dale Hooper <dchooper5@gmail.com> wrote:
Hi John,
You and Chuck have mentioned that Pluto doesn't pass the "cleared path" part of the IAU planet definition. Several astronomers have mentioned that this is a rather sloppy part of the definition. For example, several planets including earth and Jupiter have Trojan asteroids which trail and/or lead the planet by 60 degrees in the same orbit as a planet.
Also, given the current error bars - Pluto is back to being larger than any of the other known Kuiper belt objects - including Eris.
Like Chuck, I really don't have a dog in this fight - but I think that the IAU definition was poorly constructed and was created with the express desire of removing Pluto from the major planet category.
Clear skies, Dale.
On Tue, Jul 21, 2015 at 8:26 AM, John R. Peterson <docpity@earthlink.net> wrote:
One more key requirement agreed upon in 2006 was that a planet must have enough mass to sweep its orbital path clear of all other objects, and Pluto doesn't live up to this. There already known Kuiper Belt objects larger than Pluto, so should school children memorize ten, eleven, or even more, planets? And is minor planet such a bad designation?
-----Original Message-----
Date: Mon, 20 Jul 2015 21:01:52 +0000 (UTC) From: Joe Bauman <josephmbauman@yahoo.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Subject: Re: [Utah-astronomy] Pluto Planet Status Message-ID: <634580063.1148653.1437426112126.JavaMail.yahoo@mail.yahoo.com> Content-Type: text/plain; charset=UTF-8
A much stronger argument about it is that Pluto may be a great deal like other Kuiper Belt objects, and we can't have dozens of small objects identified as planets.
From: "baxman2@q.com" <baxman2@q.com> To: utah-astronomy@mailman.xmission.com Sent: Monday, July 20, 2015 12:58 PM Subject: [Utah-astronomy] Pluto Planet Status
I would personally favor Pluto being returned to official Planet status for the following reasons. It is spherical, has five months, and surface geological activity. The only argument against it, is Pluto's size being smaller than Earth's Moon, making it somewhat comparable to a number of known minor planets.
_______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Send messages to the list to Utah-Astronomy@mailman.xmission.com
The Utah-Astronomy mailing list is not affiliated with any astronomy club.
To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".
Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Send messages to the list to Utah-Astronomy@mailman.xmission.com
The Utah-Astronomy mailing list is not affiliated with any astronomy club.
To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".
participants (4)
-
Dale Hooper -
Erik Hansen -
Jeff Smith -
John R. Peterson