IS Forum
Forum Index Register Members List Events Search Today's Posts Mark Forums Read Help

Go Back   International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology
 


Welcome to the International Skeptics Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today.
Tags astronomy , telescopes

Reply
Old 18th September 2022, 09:39 PM   #1201
Pixel42
Schrödinger's cat
 
Pixel42's Avatar
 
Join Date: May 2004
Location: Malmesbury, UK
Posts: 14,980
Originally Posted by theprestige View Post
Why on earth would newspapers have a vested interest in justifying government expenditure to their readers?
Science journalists tend to have an interest in science, in my experience. My own interest in science makes me want to justify the expense of this extraordinary instrument by pointing to its remarkable discoveries, maybe theirs does too. The more remarkable (and especially unexpected) the discovery the greater the justification, and of course the better the story/number of clicks. So a little exaggeration is to be expected.
__________________
"If you trust in yourself ... and believe in your dreams ... and follow your star ... you'll still get beaten by people who spent their time working hard and learning things" - Terry Pratchett
Pixel42 is online now   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 06:25 AM   #1202
Mike Helland
Master Poster
 
Join Date: Nov 2020
Posts: 2,629
Looking at Mars:

https://www.newscientist.com/article...tures-of-mars/
Mike Helland is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 10:28 AM   #1203
RecoveringYuppy
Penultimate Amazing
 
Join Date: Nov 2006
Posts: 13,973
Originally Posted by RecoveringYuppy View Post
I am not disputing that the planet is as far as they say. I'm assuming that's correct*. I am asking what direction it is from the star so that I can break that distance down in to radial and perpendicular components.

And that is so that I can understand what valid information about size, distance, and other things can be obtained from this.

* BTW I said that to keep things simple. At the moment I can't rule out that the distance cited is the radial distance and the absolute distance may not be stated or even known.
I'm thinking the answer to discrepancies I was asking about is Airy disk issues making the planet appear bigger than it is. Mostly a guess at this point.
RecoveringYuppy is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 12:27 PM   #1204
Darat
Lackey
Administrator
 
Darat's Avatar
 
Join Date: Aug 2001
Location: South East, UK
Posts: 104,601
Will the telescope be able to look for the reluctant planet 9?
__________________
I wish I knew how to quit you
Darat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 12:45 PM   #1205
RecoveringYuppy
Penultimate Amazing
 
Join Date: Nov 2006
Posts: 13,973
Originally Posted by Darat View Post
Will the telescope be able to look for the reluctant planet 9?
Don't think we know where Planet 9 is expected to be well enough yet. I'd expect that to be considered a waste of time.
RecoveringYuppy is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 01:53 PM   #1206
Myriad
The Clarity Is Devastating
 
Myriad's Avatar
 
Join Date: Nov 2006
Location: Betwixt
Posts: 19,521
Originally Posted by RecoveringYuppy View Post
Don't think we know where Planet 9 is expected to be well enough yet. I'd expect that to be considered a waste of time.

But we should be able to get much more detailed images of Planet Claire.
__________________
A zømbie once bit my sister...
Myriad is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 01:58 PM   #1207
RecoveringYuppy
Penultimate Amazing
 
Join Date: Nov 2006
Posts: 13,973
Sorry, but pink isn't in the infrared.
RecoveringYuppy is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 02:42 PM   #1208
JesseCuster
Graduate Poster
 
Join Date: May 2016
Posts: 1,842
Originally Posted by JoeMorgue View Post
Jesus Christ I remember when people where butthurt that the Hubble didn't see God and I was hoping we'd were over that for the Webb.
JesseCuster is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 19th September 2022, 04:38 PM   #1209
BowlOfRed
Master Poster
 
BowlOfRed's Avatar
 
Join Date: Jul 2010
Location: Silicon Valley
Posts: 2,196
Originally Posted by Darat View Post
Will the telescope be able to look for the reluctant planet 9?
JWST has a pretty small field of view (I think the largest instruments are around 2' x 2'). and lot of known targets already lined up. LSST will have a much larger field (3.5 deg diameter). I think outer solar system searches have been proposed for it.
BowlOfRed is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 20th September 2022, 12:10 AM   #1210
rjh01
Gentleman of leisure
Tagger
 
rjh01's Avatar
 
Join Date: May 2005
Location: Flying around in the sky
Posts: 27,434
Originally Posted by Darat View Post
Will the telescope be able to look for the reluctant planet 9?
Originally Posted by BowlOfRed View Post
JWST has a pretty small field of view (I think the largest instruments are around 2' x 2'). and lot of known targets already lined up. LSST will have a much larger field (3.5 deg diameter). I think outer solar system searches have been proposed for it.
It would be very hard for any telescope to find planet 9. To detect it they will need to take two photos taken some time apart (maybe a year) and then compare them to look for a very faint object that has moved a little (this would be very hard). Then try to work out the orbit. Most of the objects found this way would be other things. They might have to take a third photo to make sure that they are right.

Doing this will involve taking 100's of photos and then comparing that set with another set of photos.
__________________
This signature is for rent.
rjh01 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 20th September 2022, 11:28 AM   #1211
BowlOfRed
Master Poster
 
BowlOfRed's Avatar
 
Join Date: Jul 2010
Location: Silicon Valley
Posts: 2,196
Anything we haven't found yet is going to be hard to find. . Although the idea that there would be other things found that way is also intriguing.

One of the LSST projects seems to be on characterizing the Kuiper Belt and TNOs (distribution, extent, characteristics, etc.). So looking for planet 9 would seem to fit right in (although its proposed distance might require different techniques).

ETA: from https://www.inverse.com/science/plan...ubin-telescope
Quote:
According to Jurić, there are about 4,000 known objects in the outer Solar System. Within the first two years of LSST’s mission, he thinks that number will likely grow to at least 40,000 — even 100,000 objects isn’t out of the question.
And if you find something interesting, should be able to point JWST at it and get some spectra from it.

Last edited by BowlOfRed; 20th September 2022 at 12:23 PM.
BowlOfRed is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 20th September 2022, 12:56 PM   #1212
crescent
Philosopher
 
crescent's Avatar
 
Join Date: Jul 2011
Location: Colorado
Posts: 5,085
Originally Posted by rjh01 View Post
It would be very hard for any telescope to find planet 9. To detect it they will need to take two photos taken some time apart (maybe a year) and then compare them to look for a very faint object that has moved a little (this would be very hard). Then try to work out the orbit. Most of the objects found this way would be other things. They might have to take a third photo to make sure that they are right.

Doing this will involve taking 100's of photos and then comparing that set with another set of photos.
Originally Posted by BowlOfRed View Post
Anything we haven't found yet is going to be hard to find. . Although the idea that there would be other things found that way is also intriguing.

One of the LSST projects seems to be on characterizing the Kuiper Belt and TNOs (distribution, extent, characteristics, etc.). So looking for planet 9 would seem to fit right in (although its proposed distance might require different techniques).

ETA: from https://www.inverse.com/science/plan...ubin-telescope


And if you find something interesting, should be able to point JWST at it and get some spectra from it.

As I understand it (ISFers are encouraged to correct me if I am wrong), much of the speculation regarding Planet 9 has to do with the orbital patterns of more distant known objects in the Solar System - like trans-Neptunian and Kuiper Belt things. Orbits that suggest there is something fairly big out there having influence on the orbits of the smaller objects.

So cataloging those objects along with determining their orbits could contribute to the search for the planet, or at least towards the science of determining if it exists at all. Searching for a direct image of the thing might not be in the cards, but it still "searches" for in a different sort of way, maybe narrowing down its potential location and orbit.
crescent is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 20th September 2022, 09:57 PM   #1213
Puppycow
Penultimate Amazing
 
Puppycow's Avatar
 
Join Date: Jan 2003
Location: Yokohama, Japan
Posts: 27,449
Originally Posted by Darat View Post
Will the telescope be able to look for the reluctant planet 9?
Originally Posted by RecoveringYuppy View Post
Don't think we know where Planet 9 is expected to be well enough yet. I'd expect that to be considered a waste of time.
I concur. Planet 9 may not even exist, and even if it does, they don't know where to point the telescope to see it. Time on this telescope is so valuable that I would imagine that they will only point it where they know reasonably well that something interesting will be in the field of view.

I personally think the likelihood that Planet 9 is real is rather low. The evidence seems too circumstantial and could possibly be explained by something else, such as a close encounter with a passing star or rogue planet in the past. Or something that they just haven't thought of, or just random chance.
__________________
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare

Last edited by Puppycow; 20th September 2022 at 09:58 PM.
Puppycow is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 20th September 2022, 10:37 PM   #1214
arthwollipot
Observer of Phenomena
Pronouns: he/him
 
arthwollipot's Avatar
 
Join Date: Feb 2005
Location: Ngunnawal Country
Posts: 77,932
Originally Posted by Puppycow View Post
I concur. Planet 9 may not even exist, and even if it does, they don't know where to point the telescope to see it. Time on this telescope is so valuable that I would imagine that they will only point it where they know reasonably well that something interesting will be in the field of view.
Like Mars.

NASA's James Webb Telescope captures its first pictures of Mars despite challenges posed by 'extreme brightness'

Quote:
Months after dazzling the world with the deepest view of the cosmos ever captured, NASA's James Webb Telescope has turned its gaze to something much closer to home — Mars.

NASA has published the first round of images of Mars captured by the $13 billion telescope, a collaboration with ESA (European Space Agency) and CSA (Canadian Space Agency), with more research to come.

Featuring the Huygens Crater, Hellas Basin and the Syrtis Major, the batch of images was taken on September 5.

The James Webb Telescope is orbiting around the Sun at a distance of about 1.5 million kilometres from Earth.

This unique position means the telescope can study short-term phenomena like dust storms and weather patterns, NASA said in a blog post.

However, there were some challenges...
__________________
? > !
arthwollipot is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 01:57 AM   #1215
Puppycow
Penultimate Amazing
 
Puppycow's Avatar
 
Join Date: Jan 2003
Location: Yokohama, Japan
Posts: 27,449
TBH, we already have lots of great images of the planets in our own solar system from other missions. Cassini for Saturn, Juno for Jupiter, New Horizons for Pluto. JWST will not be able to produce higher resolution images of those objects than we already possess from other missions that studied them from up close.
__________________
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare
Puppycow is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 02:15 AM   #1216
Pixel42
Schrödinger's cat
 
Pixel42's Avatar
 
Join Date: May 2004
Location: Malmesbury, UK
Posts: 14,980
I guess the difference is the telescope can look at the planets at any time, probes have a limited observing time. So if something particularly interesting happened whilst there was no orbiting probe - if Jupiter's red spot suddenly disappeared or something - we could still observe it.
__________________
"If you trust in yourself ... and believe in your dreams ... and follow your star ... you'll still get beaten by people who spent their time working hard and learning things" - Terry Pratchett
Pixel42 is online now   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 02:51 AM   #1217
Darat
Lackey
Administrator
 
Darat's Avatar
 
Join Date: Aug 2001
Location: South East, UK
Posts: 104,601
Originally Posted by crescent View Post
As I understand it (ISFers are encouraged to correct me if I am wrong), much of the speculation regarding Planet 9 has to do with the orbital patterns of more distant known objects in the Solar System - like trans-Neptunian and Kuiper Belt things. Orbits that suggest there is something fairly big out there having influence on the orbits of the smaller objects.

So cataloging those objects along with determining their orbits could contribute to the search for the planet, or at least towards the science of determining if it exists at all. Searching for a direct image of the thing might not be in the cards, but it still "searches" for in a different sort of way, maybe narrowing down its potential location and orbit.
That's why I was wondering if the Webb could be used once we think we know where it should be with more certainty then we currently have. It was seeing the images from Jupiter and Mars that made me think about it. I don't know why but I had thought the local planets would have been "too bright" i.e. too hot for the Webb to get good images.
__________________
I wish I knew how to quit you
Darat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 03:37 AM   #1218
ohms
Graduate Poster
 
ohms's Avatar
 
Join Date: Apr 2005
Posts: 1,467
Bit of an issue with the MIRI medium-resolution spectroscopy mode.

https://blogs.nasa.gov/webb/2022/09/...ations-update/

Hopefully they will find a work around or fix to bring the instrument back up to its full capabilities.
__________________
Long time lurker
ohms is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 05:37 AM   #1219
RecoveringYuppy
Penultimate Amazing
 
Join Date: Nov 2006
Posts: 13,973
Originally Posted by ohms View Post
Bit of an issue with the MIRI medium-resolution spectroscopy mode.

https://blogs.nasa.gov/webb/2022/09/...ations-update/

Hopefully they will find a work around or fix to bring the instrument back up to its full capabilities.
Short version: the grating wheel is grating.
RecoveringYuppy is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 06:18 AM   #1220
RecoveringYuppy
Penultimate Amazing
 
Join Date: Nov 2006
Posts: 13,973
Originally Posted by Darat View Post
That's why I was wondering if the Webb could be used once we think we know where it should be with more certainty then we currently have.
Originally Posted by BowlOfRed View Post
JWST has a pretty small field of view (I think the largest instruments are around 2' x 2'). and lot of known targets already lined up. LSST will have a much larger field (3.5 deg diameter). I think outer solar system searches have been proposed for it.
That roughly translates to dividing the sky up in to 40 million "pixels". If you want to look at something specific you have to know which of those pixels it's in.
RecoveringYuppy is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 06:53 AM   #1221
Puppycow
Penultimate Amazing
 
Puppycow's Avatar
 
Join Date: Jan 2003
Location: Yokohama, Japan
Posts: 27,449
Originally Posted by Darat View Post
I don't know why but I had thought the local planets would have been "too bright" i.e. too hot for the Webb to get good images.
In fact, they are. At least Mars is. The images we got are not even close to the best images we have of Mars.

Quote:
"Webb's instruments are so sensitive that without special observing techniques, the bright infrared light from Mars is blinding, causing a phenomenon known as detector saturation," NASA's blog post said.

"Astronomers adjusted for Mars' extreme brightness by using very short exposures, measuring only some of the light that hit the detectors, and applying special data analysis techniques."
__________________
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare
Puppycow is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 08:54 AM   #1222
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by Puppycow View Post
I concur. Planet 9 may not even exist
Should be planet 11.

Everyone knows that Pluto was done dirty. Which might lead you to think this should be planet 10. But we have largely forgotten that Ceres was once a planet too, and deserves just as much respect as Pluto.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 03:56 PM   #1223
Samson
Penultimate Amazing
 
Join Date: Oct 2013
Posts: 10,096
Originally Posted by Ziggurat View Post
Should be planet 11.

Everyone knows that Pluto was done dirty. Which might lead you to think this should be planet 10. But we have largely forgotten that Ceres was once a planet too, and deserves just as much respect as Pluto.
Agree on Pluto.
It's got moons so a shoe in for planet status.
I bet it gets brought back soon.
So looking for 10.

Last edited by Samson; 21st September 2022 at 03:58 PM.
Samson is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 04:01 PM   #1224
Ryan O'Dine
OD’ing on Damitol
 
Ryan O'Dine's Avatar
 
Join Date: Nov 2004
Location: Walk in an ever expanding Archimedean spiral and you'll find me eventually
Posts: 1,935
Originally Posted by Puppycow View Post
In fact, they are. At least Mars is. The images we got are not even close to the best images we have of Mars.
I don't know, the images look pretty good to me. You can almost see the canals.
__________________
I collect people like you in little formaldehyde bottles in my basement. (Not a threat. A hobby.)
Ryan O'Dine is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 04:38 PM   #1225
3point14
Pi
 
3point14's Avatar
 
Join Date: Nov 2005
Posts: 21,400
Originally Posted by RecoveringYuppy View Post
That roughly translates to dividing the sky up in to 40 million "pixels". If you want to look at something specific you have to know which of those pixels it's in.
That really helps. Thanks.
__________________
Up the River!

Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]
3point14 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 21st September 2022, 08:39 PM   #1226
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by Samson View Post
Agree on Pluto.
It's got moons so a shoe in for planet status.
I bet it gets brought back soon.
So looking for 10.
Mercury has no moons. Neither does Venus. Why should that keep Ceres out?
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 01:17 AM   #1227
Puppycow
Penultimate Amazing
 
Puppycow's Avatar
 
Join Date: Jan 2003
Location: Yokohama, Japan
Posts: 27,449
Well if you really want to include Ceres, which is smaller than Charon, the moon of Pluto, then I guess we would end up with a lot more planets than just 10 or 11, wouldn't we?

Would our own moon count? It's bigger than Ceres. Also some TNOs. Many other moons of the gas giant planets are also bigger than Ceres.
__________________
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare
Puppycow is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 06:02 AM   #1228
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by Puppycow View Post
Well if you really want to include Ceres, which is smaller than Charon, the moon of Pluto, then I guess we would end up with a lot more planets than just 10 or 11, wouldn't we?
Yes, we would have more than 11, but not moons.

Quote:
Would our own moon count? It's bigger than Ceres.
No, definitely not. This is already settled: Ganymede is larger than Mercury, but it's a moon and not a planet because it orbits a planet. Our moon would not count either, for the same reason. Charon is a closer call since Charon and Pluto orbit a barycenter outside of Pluto, so one could argue that they both orbit each other, but I'd still call it a moon because it's still significantly smaller than Pluto.

Other object like Eris would also be planets, but I'm OK with pushing their numbering past 11, so that the mystery large planet becomes planet 11.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 12:46 PM   #1229
ThatGuy11200
Critical Thinker
 
Join Date: Jan 2018
Location: London
Posts: 423
Originally Posted by Puppycow View Post
Well if you really want to include Ceres, which is smaller than Charon, the moon of Pluto, then I guess we would end up with a lot more planets than just 10 or 11, wouldn't we?

Would our own moon count? It's bigger than Ceres. Also some TNOs. Many other moons of the gas giant planets are also bigger than Ceres.
Why should it matter that there are more than some arbitrarily small number?
ThatGuy11200 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 01:56 PM   #1230
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by ThatGuy11200 View Post
Why should it matter that there are more than some arbitrarily small number?
I think his point was that the mystery planet might not end up as planet 11, but as some higher number. But we wouldn't need to order them by orbital radius. In fact, it's probably the wrong way to do it, since then numbers for known planets might change over time as new planets are discovered.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 05:11 PM   #1231
Puppycow
Penultimate Amazing
 
Puppycow's Avatar
 
Join Date: Jan 2003
Location: Yokohama, Japan
Posts: 27,449
Originally Posted by ThatGuy11200 View Post
Why should it matter that there are more than some arbitrarily small number?
Originally Posted by Ziggurat View Post
I think his point was that the mystery planet might not end up as planet 11, but as some higher number. But we wouldn't need to order them by orbital radius. In fact, it's probably the wrong way to do it, since then numbers for known planets might change over time as new planets are discovered.
Only in the sense that it becomes increasingly difficult to commit all of them to memory.
__________________
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare
Puppycow is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 05:37 PM   #1232
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by Puppycow View Post
Only in the sense that it becomes increasingly difficult to commit all of them to memory.
It also complicates written records that refer to planet numbering.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd September 2022, 09:06 PM   #1233
ThatGuy11200
Critical Thinker
 
Join Date: Jan 2018
Location: London
Posts: 423
Originally Posted by Puppycow View Post
Only in the sense that it becomes increasingly difficult to commit all of them to memory.
That was one of the arguments put forward at the IAU, but I don't understand why that would matter.

Originally Posted by Ziggurat View Post
It also complicates written records that refer to planet numbering.
So?

I have training in biological taxonomy. Species names undergo revision frequently. This "complicates written records", but scientists are generally smart enough that it doesn't matter.
ThatGuy11200 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 12:33 AM   #1234
rjh01
Gentleman of leisure
Tagger
 
rjh01's Avatar
 
Join Date: May 2005
Location: Flying around in the sky
Posts: 27,434
Originally Posted by Puppycow View Post
Well if you really want to include Ceres, which is smaller than Charon, the moon of Pluto, then I guess we would end up with a lot more planets than just 10 or 11, wouldn't we?

Would our own moon count? It's bigger than Ceres. Also some TNOs. Many other moons of the gas giant planets are also bigger than Ceres.
If you want to define a planet as something ball-shaped that orbits the sun we would have hundreds of planets. There are many such objects orbiting at similar distances to Neptune and Pluto or further. That is why Pluto was downgraded.
__________________
This signature is for rent.
rjh01 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 01:14 AM   #1235
3point14
Pi
 
3point14's Avatar
 
Join Date: Nov 2005
Posts: 21,400
The currently used definition of planet seems to me to be extremely logical and appropriate. I really don't get why some have so much of an issue with it.
__________________
Up the River!

Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]
3point14 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 01:49 AM   #1236
Samson
Penultimate Amazing
 
Join Date: Oct 2013
Posts: 10,096
Originally Posted by rjh01 View Post
If you want to define a planet as something ball-shaped that orbits the sun we would have hundreds of planets. There are many such objects orbiting at similar distances to Neptune and Pluto or further. That is why Pluto was downgraded.
That is a beautiful point.
We must look forward to scores of flybys like the Pluto Horizon to prove what an irrelevant object Pluto is. (And of course girlfriend Sharon).

Now back to thread, ..
Samson is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 05:54 AM   #1237
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by ThatGuy11200 View Post
So?
So it's better to avoid it if there's no good reason not to avoid it. The fact that you can work around a problem isn't an excuse to create it unnecessarily. And really, what does ordering it by radius give you anyways? Once we're including the TNO planets, average radius can be quite different than instantaneous radius, and many of the orbits cross as well, so the ordering of average radius isn't really important or informative. There's no reason to maintain it for those planets in the first place.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 05:58 AM   #1238
Pixel42
Schrödinger's cat
 
Pixel42's Avatar
 
Join Date: May 2004
Location: Malmesbury, UK
Posts: 14,980
I'm pretty sure that, if the nature of Pluto and the fact that it was just one of many such objects in a large belt had been understood when it was first discovered, it would never have been classified as a planet in the first place.
__________________
"If you trust in yourself ... and believe in your dreams ... and follow your star ... you'll still get beaten by people who spent their time working hard and learning things" - Terry Pratchett
Pixel42 is online now   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 06:10 AM   #1239
Ziggurat
Penultimate Amazing
 
Ziggurat's Avatar
 
Join Date: Jun 2003
Posts: 52,270
Originally Posted by rjh01 View Post
If you want to define a planet as something ball-shaped that orbits the sun we would have hundreds of planets.
No, not "ball shaped". It's got to be something that's gravitationally shaped into hydrostatic equilibrium. Vesta is "ball shaped", but it's not in hydrostatic equilibrium.

And I don't think we're looking at hundreds, I think we're looking at dozens. But what's wrong with that? Why do we have to cap the number?

And I don't know of a better definition of what counts as a planet. The excuse to downgrade Pluto (not clearing its orbit) doesn't really make sense, because the definition then becomes contingent upon factors other than the object's own properties, and it can change over time in either direction (being promoted to or demoted from planet status) because of what happens elsewhere. Even at its present mass, Jupiter wouldn't have been considered a planet early on in the solar system's history. And if we do find the hypothesized planet 9 (should be 11), it wouldn't be a full fledged planet even at several times Earth's mass if it hasn't cleared its orbit either, which it probably hasn't. I find that ridiculous.
__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
Ziggurat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 23rd September 2022, 06:59 AM   #1240
3point14
Pi
 
3point14's Avatar
 
Join Date: Nov 2005
Posts: 21,400
Originally Posted by Ziggurat View Post
No, not "ball shaped". It's got to be something that's gravitationally shaped into hydrostatic equilibrium. Vesta is "ball shaped", but it's not in hydrostatic equilibrium.

And I don't think we're looking at hundreds, I think we're looking at dozens. But what's wrong with that? Why do we have to cap the number?

And I don't know of a better definition of what counts as a planet. The excuse to downgrade Pluto (not clearing its orbit) doesn't really make sense, because the definition then becomes contingent upon factors other than the object's own properties, and it can change over time in either direction (being promoted to or demoted from planet status) because of what happens elsewhere. Even at its present mass, Jupiter wouldn't have been considered a planet early on in the solar system's history. And if we do find the hypothesized planet 9 (should be 11), it wouldn't be a full fledged planet even at several times Earth's mass if it hasn't cleared its orbit either, which it probably hasn't. I find that ridiculous.

I think 'having cleared it's own orbit' is a perfect definition for a planet. That it may not have applied a loooong time ago or might not again in a far distant future doesn't present me with any issues at all.

A planet is the only thing in it's own orbit that is orbiting the sun. That works for me.

I have never really understood the 'oh, poor Pluto' thing. It's a rock more miles away than can fit into my brain, it doesn't care.
__________________
Up the River!

Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]
3point14 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Reply

International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 08:25 PM.
Powered by vBulletin. Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.

This forum began as part of the James Randi Education Foundation (JREF). However, the forum now exists as
an independent entity with no affiliation with or endorsement by the JREF, including the section in reference to "JREF" topics.

Disclaimer: Messages posted in the Forum are solely the opinion of their authors.