| |
Main
Date: 05 Oct 2006 08:03:48
From: Magnificent Universe
Subject: Test Your Pluto Knowledge, Part Two!
|
Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
Jupiter, and Saturn.
But how many of these planets would still be visible to the naked eye if
they were as far as Pluto's mean distance from the Sun (39.5 astronomical
units, or 3.7 billion miles)?
A. All of them.
B. All but Mercury.
C. Only Jupiter and Saturn, the two largest.
D. None of them.
Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
Correct email: MagnificentUniverse "at" yahoo "dot" com.
|
|
| |
Date: 05 Oct 2006 08:45:02
From: George Dishman
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
Magnificent Universe wrote:
> Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
> Jupiter, and Saturn.
>
> But how many of these planets would still be visible to the naked eye if
> they were as far as Pluto's mean distance from the Sun (39.5 astronomical
> units, or 3.7 billion miles)?
>
> A. All of them.
>
> B. All but Mercury.
>
> C. Only Jupiter and Saturn, the two largest.
>
> D. None of them.
>
> Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
Here are two questions for you then Ken, I won't
bother with choices, I'm sure you know the answers:
1. How many satellites of planets are more massive
than the least massive planet?
2. How many satellites of planets are more massive
than Pluto?
George
|
| | |
Date: 06 Oct 2006 02:04:35
From: Father Khym
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
George Dishman wrote:
> Magnificent Universe wrote:
> > Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
> > Jupiter, and Saturn.
> >
> > But how many of these planets would still be visible to the naked eye if
> > they were as far as Pluto's mean distance from the Sun (39.5 astronomical
> > units, or 3.7 billion miles)?
> >
> > A. All of them.
> >
> > B. All but Mercury.
> >
> > C. Only Jupiter and Saturn, the two largest.
> >
> > D. None of them.
> >
> > Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
>
> Here are two questions for you then Ken, I won't
> bother with choices, I'm sure you know the answers:
>
> 1. How many satellites of planets are more massive
> than the least massive planet?
>
> 2. How many satellites of planets are more massive
> than Pluto?
>
> George
Play with yourself much?
|
| |
Date: 05 Oct 2006 18:12:16
From:
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
CeeBee wrote:
> "Magnificent Universe" <MagnificentUniverse@yyyyy.com> wrote in sci.astro:
> > visible to the naked eye
> I think it's inappropriate to talk in a public usenet group about "naked"
> eyes. Our fragile youth might be reading. The "unaided eye" might be more
> appropriate although it still contains exposed body parts. I suggest
> "visible without using a device that magnifies your field of view".
> Also it's inappropriate to talk about Pluto. I don't know why, but someone
> will come up with a reason eventually, if you wait long enough.
I think you may be having Pluto confused with the second planet in from
it. However, the problems with *that* planet can simply be solved by
referring to it by its Greek name rather than its Latin name - so we
can call it Ouranos, which is quite safe from causing any misguided
titters from the back row.
John Savard
|
| |
Date: 05 Oct 2006 19:28:45
From: MikeC
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
"Magnificent Universe" <MagnificentUniverse@yyyyy.com > wrote in message
news:4525200b$0$96233$742ec2ed@news.sonic.net...
> Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
> Jupiter, and Saturn.
>
> But how many of these planets would still be visible to the naked eye if
> they were as far as Pluto's mean distance from the Sun (39.5 astronomical
> units, or 3.7 billion miles)?
>
> A. All of them.
>
> B. All but Mercury.
>
> C. Only Jupiter and Saturn, the two largest.
>
> D. None of them.
D. None of them. Because if they were all that far out, they'd be in the
same orbit, which would mean they haven't cleared their orbit and so they
wouldn't be planets.
(Do I win?)
|
| | |
Date: 06 Oct 2006 01:44:13
From:
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
MikeC writes:
> Magnificent Universe wrote:
>> Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
>> Jupiter, and Saturn.
>>
>> But how many of these planets would still be visible to the naked eye if
>> they were as far as Pluto's mean distance from the Sun (39.5 astronomical
>> units, or 3.7 billion miles)?
>>
>> A. All of them.
>>
>> B. All but Mercury.
>>
>> C. Only Jupiter and Saturn, the two largest.
>>
>> D. None of them.
> D. None of them. Because if they were all that far out, they'd be in the
> same orbit, which would mean they haven't cleared their orbit and so they
> wouldn't be planets.
>
> (Do I win?)
Yes, but not for the reason given.
|
| | |
Date: 06 Oct 2006 01:40:05
From: Ken Arromdee
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
In article <eg44cn$pcn$1@emma.aioe.org >,
MikeC <sendmail@tosomebodywhocares.com > wrote:
>D. None of them. Because if they were all that far out, they'd be in the
>same orbit, which would mean they haven't cleared their orbit and so they
>wouldn't be planets.
>
>(Do I win?)
I didn't think about it enough, went to the site, and was surprised by the
answer, which is "none of them" for a far more prosaic reason. An object's
brightness varies as the square of its distance from the light source. It
also varies as the square of its distance from the viewer. The overall
effect is that the object's brightness varies as the *fourth power* of its
distance from us (if the light source and viewer are at about the same distance
away).
In other words, an object's brightness drops off very rapidly. None of the
planets would be visible to the naked eye at the distance of Pluto (maybe
Jupiter just barely.)
There's also his question 1: How bright would Pluto be at closest approach
if it was in the orbit of Mars? The answer is "brighter than every star
except the sun", for the same reason.
--
Ken Arromdee / arromdee_AT_rahul.net / http://www.rahul.net/arromdee
"You know, you blow up one sun and suddenly everyone expects you to walk
on water." --Samantha Carter, Stargate SG-1
|
| |
Date: 05 Oct 2006 22:40:49
From: james
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
On Thu, 5 2006 08:03:48 -0700, "Magnificent Universe"
<MagnificentUniverse@yyyyy.com > wrote:
>+++Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
>+++Jupiter, and Saturn.
>+++
>+++But how many of these planets would still be visible to the naked eye if
>+++they were as far as Pluto's mean distance from the Sun (39.5 astronomical
>+++units, or 3.7 billion miles)?
>+++
>+++A. All of them.
>+++
>+++B. All but Mercury.
>+++
>+++C. Only Jupiter and Saturn, the two largest.
>+++
>+++D. None of them.
>+++
>+++Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
>+++
>+++Correct email: MagnificentUniverse "at" yahoo "dot" com.
>+++
************
does not matter since I don't plan on visiting any of them in the near
future.
james
|
| |
Date: 05 Oct 2006 21:04:27
From: CeeBee
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
"Magnificent Universe" <MagnificentUniverse@yyyyy.com > wrote in sci.astro:
> visible to the naked eye
I think it's inappropriate to talk in a public usenet group about "naked"
eyes. Our fragile youth might be reading. The "unaided eye" might be more
appropriate although it still contains exposed body parts. I suggest
"visible without using a device that magnifies your field of view".
Also it's inappropriate to talk about Pluto. I don't know why, but someone
will come up with a reason eventually, if you wait long enough.
--
CeeBee
*** Got no wockin' furries ***
|
| | |
Date: 05 Oct 2006 16:07:56
From: Brian Tung
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
CeeBee wrote:
> I think it's inappropriate to talk in a public usenet group about "naked"
> eyes. Our fragile youth might be reading. The "unaided eye" might be more
> appropriate although it still contains exposed body parts. I suggest
> "visible without using a device that magnifies your field of view".
I suspect you're joking, but there *was* a bit of a fooferaw over this
exact phrasing ("naked eye" vs "unaided eye") because some primitive
news filter caught the word "naked" out of context and either blocked
the message or cut the inappropriate word out with a pair of scissors.
Hopefully, any such filter has been made redundant, but at any rate, I
do in fact use "unaided eye" instead of "naked eye," in commemoration of
that squabble.
:)
--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
|
| | | |
Date: 06 Oct 2006 11:49:27
From: CeeBee
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
brian@isi.edu (Brian Tung) wrote in sci.astro.amateur:
> I suspect you're joking, but there *was* a bit of a fooferaw over this
> exact phrasing ("naked eye" vs "unaided eye") because some primitive
> news filter caught the word "naked" out of context and either blocked
> the message or cut the inappropriate word out with a pair of scissors.
>
> Hopefully, any such filter has been made redundant, but at any rate, I
> do in fact use "unaided eye" instead of "naked eye," in commemoration of
> that squabble.
>
>:)
I once had a simple website called "astronomy as a hobby" aimed at
beginners. I discovered it was filtered out by the first generation
"decency" software because of the repeated phrase "naked eye"; so it isn't
that uncommon to happen.
--
CeeBee
*** Democracy is not a spectator sport ***
|
| | |
Date: 05 Oct 2006 21:12:28
From:
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
CeeBee writes:
> Magnificent Universe wrote:
>> visible to the naked eye
> I think it's inappropriate to talk in a public usenet group about "naked"
> eyes. Our fragile youth might be reading. The "unaided eye" might be more
> appropriate although it still contains exposed body parts. I suggest
> "visible without using a device that magnifies your field of view".
Telescopes do not magnify your field of view. They reduce it quite
substantially. They magnify what's in the field of view, but the
field of view itself is much smaller than for the unaided eye.
|
| |
Date: 05 Oct 2006 12:32:19
From: Don't Be Evil
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
Magnificent Universe wrote:
> Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
> Jupiter, and Saturn.
>
> But how many of these planets would still be visible to the naked eye if
> they were as far as Pluto's mean distance from the Sun (39.5 astronomical
> units, or 3.7 billion miles)?
>
> A. All of them.
>
> B. All but Mercury.
>
> C. Only Jupiter and Saturn, the two largest.
>
> D. None of them.
>
> Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
>
> Correct email: MagnificentUniverse "at" yahoo "dot" com.
Troll-meter goes beep beep beep beep beep beep
beepbeepbeepbeeeeeee...
|
| | |
Date: 05 Oct 2006 21:20:36
From: CeeBee
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
"Don't Be Evil" <g626700-gg@yahoo.com > wrote in sci.astro.amateur:
> Troll-meter goes beep beep beep beep beep beep
> beepbeepbeepbeeeeeee...
How long does your meter do with a set of AA-batteries?
--
CeeBee
*** Democracy is not a spectator sport ***
|
| |
Date: 06 Oct 2006 05:18:35
From: Terry A Haimann
Subject: Re: Test Your Pluto Knowledge, Part Two!
|
Mercury 512.319293859178
Venus 232.77334978041
Mars 89.5426813370111
Jupiter 13.9970485567221
Saturn 7.08562834442293
Uranus 7.11140265650629
Neptune 8.18826841942277
On Thu, 05 2006 08:03:48 -0700, Magnificent Universe wrote:
> Five planets are quite bright in Earth's sky: Mercury, Venus, Mars,
> Jupiter, and Saturn.
>
> But how many of these planets would still be visible to the naked eye if
> they were as far as Pluto's mean distance from the Sun (39.5 astronomical
> units, or 3.7 billion miles)?
>
> A. All of them.
>
> B. All but Mercury.
>
> C. Only Jupiter and Saturn, the two largest.
>
> D. None of them.
>
> Find out the correct answer at http://KenCroswell.com/PlutoQuestion2.html .
>
> Correct email: MagnificentUniverse "at" yahoo "dot" com.
|
|
