APOD: Jupiter and Io (2012 Nov 28)

[Anthony Barreiro]

"Dance of the Planets", round and round ad infinitum.

I've been waiting for Chris to remind us that the planets will not orbit the Sun for an infinite length of time, explaining the relevant orbital mechanics and the effects of the evolution of the Sun itself ... .

[flash]

I cannot help but think of this little bit of verse when seeing an image of Jupiter and Io: http://www.baltastro.org/AstroPoetry.html#JupiterAndTen

I agree. "Jupiter and Ten" sounds considerably more frustratingly fascinating than "Jupiter and Io" (Jupiter and IO?)

Ann

Reminds me of an old quip:
"There are 10 (not ten) kinds of people in the world: Those who understand binary and those who don't!"

[bystander]

Reminds me of an old quip:
"There are ten kinds of people in the world: Those who understand binary and those who don't!"

That joke only works if you write it
"There are 10 kinds of people ..."
Ten is a word that means, well, ten, not two.

[Beyond]

Reminds me of an old quip:
"There are ten kinds of people in the world: Those who understand binary and those who don't!"

That joke only works if you write it
"There are 10 kinds of people ..."
Ten is a word that means, well, ten, not two.

Well... he did 'write' it, so according to what you said, the joke worked. And of course ten means ten, so why did you say what you said, bystander?

[bystander]

Well... he did 'write' it, so according to what you said, the joke worked. And of course ten means ten, so why did you say what you said, bystander?

10 in binary is not ten, it's two. The joke makes no sense if you use the word ten.

"There are 10 ten kinds of people in the world: Those who understand binary and those who don't!"

[Ann]

Well... he did 'write' it, so according to what you said, the joke worked. And of course ten means ten, so why did you say what you said, bystander?

10 in binary is not ten, it's two. The joke makes no sense if you use the word ten.

"There are 10 ten kinds of people in the world: Those who understand binary and those who don't!"

Ummm. I feel like the "0" part of the "10" here. I remember a little - make that a microscopic tiny amount - of the binary stuff we were taught in school. And that was back in the seventies, long before ordinary people knew what a computer was.

By the way, bystander, how do you write "70" (seventy) as a binary number, in base 2? And what is "base 2 70" in ordinary base 10?

Ann

[Beyond]

Well... he did 'write' it, so according to what you said, the joke worked. And of course ten means ten, so why did you say what you said, bystander?

10 in binary is not ten, it's two. The joke makes no sense if you use the word ten.

"There are 10 ten kinds of people in the world: Those who understand binary and those who don't!"

Ummm. I feel like the "0" part of the "10" here. I remember a little - make that a microscopic tiny amount - of the binary stuff we were taught in school. And that was back in the seventies, long before ordinary people knew what a computer was.

By the way, bystander, how do you write "70" (seventy) as a binary number, in base 2? And what is "base 2 70" in ordinary base 10?

Ann

I'm in the same "0" boat as ann, but w-a-y at the back, hanging off the stern by my fingernails.

[bystander]

By the way, bystander, how do you write "70" (seventy) as a binary number, in base 2?

1000110

And what is "base 2 70" in ordinary base 10?

There is no '7' in binary, only '1' and '0'.

[JohnD]

I do know differently, John. Differently is a friend of mine.

If Io was lying on the surface of Jupiter its shadow would be directly under it
as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).
http://space.jpl.nasa.gov/cgi-bin/wspac ... 1&showac=1

If Io was just one Jupiter radius above the surface of Jupiter
its shadow would be ~ 3.6º east longitude on Jupiter as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).

Since Io is ~ 5 Jupiter radii above the surface of Jupiter
its shadow is ~ 18º east longitude on Jupiter as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).

Thank you neufer! I now have a different perspective of your view.
But not the relevance of your link, which shows the Inner System from Jupiter.
Can that view be adapted to show, even animate, the Earth view of Jupiter?
JOhn

[DavidLeodis]

The posts about the name IO looking like 10 (ten) got me wondering, so just for fun:-

10 (decimal) is A (hexadecimal base 16).
10 (hexadecimal) is 16 (decimal).
10 (hexadecimal colours) is a shade of blue.
10 (decimal) is 12 (octal base 8).
10 (octal) is 8 (decimal).

It's a shame that IO is not blue!

[neufer]

I do know differently, John. Differently is a friend of mine.

If Io was lying on the surface of Jupiter its shadow would be directly under it
as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).
http://space.jpl.nasa.gov/cgi-bin/wspac ... 1&showac=1

If Io was just one Jupiter radius above the surface of Jupiter
its shadow would be ~ 3.6º east longitude on Jupiter as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).

Since Io is ~ 5 Jupiter radii above the surface of Jupiter
its shadow is ~ 18º east longitude on Jupiter as viewed from Earth (~ 3.6º off the Sun-Jupiter axis).

Thank you neufer! I now have a different perspective of your view.
But not the relevance of your link, which shows the Inner System from Jupiter.
Can that view be adapted to show, even animate, the Earth view of Jupiter?
JOhn

The perspective was to show the ~ 3.6º angle between the Earth & the Sun as seen from Jupiter.

One can also approximate the angle by remembering that
the Earth moves ~ 1º daily in it's orbit about the Sun
and this was 16 days before opposition so it is ~ 16º.

From Jupiter at 5.2 AU that Earth orbital angle appears to be only ~ 16º/(5.2-1) = ~ 3.8º .

[Since Jupiter is orbiting as well once every 12 years
(such that Earth passes Jupiter only 11 times in 12 years)
this reduces to ~ 3.8º x 11/12 = 3.5º.]

The (shadowless) view of Jupiter from Earth shows the position on Io, itself, on Nov. 17 00:00UT:
http://space.jpl.nasa.gov/cgi-bin/wspac ... 1&showac=1

The view of Jupiter from the Sun indicates the position on Io's shadow on Nov. 17 00:00UT:
http://space.jpl.nasa.gov/cgi-bin/wspac ... 1&showac=1

[PhilT]

No one has mentioned that the 17 days to opposition also means that we are not viewing the shadow with the sun directly behind us but rather from a considerable bit to the side - 17 days means something like 36 degrees to the side (~360 * 17/365/2).

By the way, no comments in reply to my original cooling effect question yet !!!!!!

BR/P
PS Yes, I know Jupiter is moving too, I'm just illustrating that it's no surprise that the shadow is offset.

[Ann]

By the way, bystander, how do you write "70" (seventy) as a binary number, in base 2?

1000110

Click to play embedded YouTube video.

I still think too much learning might shrivel your brain.

Ann

[Beyond]

I still think too much learning might shrivel your brain.

D'OH!