APOD: Europa and Jupiter from Voyager 1 (2020 Jun 28)

[APOD Robot]

Europa and Jupiter from Voyager 1

Explanation: What are those spots on Jupiter? Largest and furthest, just right of center, is the Great Red Spot -- a huge storm system that has been raging on Jupiter possibly since Giovanni Cassini's likely notation of it 355 years ago. It is not yet known why this Great Spot is red. The spot toward the lower left is one of Jupiter's largest moons: Europa. Images from Voyager in 1979 bolster the modern hypothesis that Europa has an underground ocean and is therefore a good place to look for extraterrestrial life. But what about the dark spot on the upper right? That is a shadow of another of Jupiter's large moons: Io. Voyager 1 discovered Io to be so volcanic that no impact craters could be found. Sixteen frames from Voyager 1's flyby of Jupiter in 1979 were recently reprocessed and merged to create the featured image. About 43 years ago, Voyager 1 launched from Earth and started one of the greatest explorations of the Solar System ever.

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[Ann]

Today's APOD is a golden oldie, and a very good-looking one.

I remember how excited I was when Voyager 1 started sending home its pictures of Jupiter. They were glorious. Maybe that's why I was so disappointed at Voyager 1's pictures of Saturn. Saturn looked so bland compared with Jupiter, and I had my first ever experience of obvious false color. One of the Voyager 1 pictures of Saturn was wildly psychedelic, painted in stripes of green, cyan and purple.

I have preferred Jupiter over Saturn ever since. You see what color can do to a crazy color nerd like me.

Ann

[orin stepanek]

To me, the red spot on this photo looks like a hole opening deep into Jupiter!

[heehaw]

We've spotted Europa!

[Dioskur]

This photo is weird. Look at the shadow on the moon - it's on the left side of it. Sunlight clearly comes from the right of this picture. So how come Europa's shadow on the Jupiter is being cast almost in the opposite direction?

[Dioskur]

Nevermind - it's stated that it's Io's shadow. I must've been still half-asleep when I read the description. I'm sorry for the commotion.

[Chris Peterson]

I remember how excited I was when Voyager 1 started sending home its pictures of Jupiter.

I was at Caltech at the time. No Internet as such back then, but they set up a private feed between JPL and Beckman Auditorium on campus, and projected the JPL monitors up onto a big screen. We were there to watch the very first images come in, unprocessed, slowly painting from top to bottom. Amazing, indeed!

(Curiously, I was actually working with the Viking project - Mars- at the time.)

[johnnydeep]

Nevermind - it's stated that it's Io's shadow. I must've been still half-asleep when I read the description. I'm sorry for the commotion.

FYI, you can edit your own posts to add corrections or clarifications!

[bystander]

FYI, you can edit your own posts to add corrections or clarifications!

Not if your not a member.

[neufer]

---

Surprise! Big Jupiter Moons Shine Even When Eclipsed
By Charles Q. Choi June 23, 2014

<<When eclipsed [by Jupiter], the luminosity of these moons was one-millionth to one-ten-millionth of their uneclipsed brightness — dim enough for the phenomenon to remain undetected until now, even though researchers have observed the Galilean moons in eclipse for centuries.

It remains uncertain what causes the slight brightening. However, Kohji Tsumura, an astronomer at Tohoku University in Japan, and his colleagues believe the upper part of Jupiter's atmosphere may be responsible. [Tsumura and his colleagues detailed their findings in the July 10 issue of The Astronomical Journal.]

Jupiter's clouds, which give the giant planet its striped appearance, grow from tiny particles called aerosols or hazes. Prior studies have hinted that these hazes form in the upper part of Jupiter's atmosphere. The researchers suggested that hazes in the upper atmosphere may scatter sunlight onto the Galilean satellites, illuminating them. This effect is similar to the one that causes Earth's moon to look red during a total lunar eclipse.

The new finding could help scientists analyze the hazes in Jupiter's atmosphere, which are otherwise difficult to study. By studying the spectrum of light from the eclipsed Jupiter moons, the researchers could learn about the compositions of the hazes, Tsumura said. In addition, this new method of studying Jupiter's upper atmosphere could help researchers investigate the atmospheres of exoplanets around distant stars. Exoplanets are often seen when they pass in front of their stars, and scientists can glean details about their atmospheres when starlight passes through them. "It is important to study sunlight transmitted through the atmospheres of the planets in our solar system for comparison with light through the atmospheres around the exoplanets," Tsumura said.>>

[ta152h0]

Yesterday I saw, on a TY program, How the Universe Works, that the moon is possibly hollow. Is that still being looked at? pass the ice cold one.

[Chris Peterson]

Yesterday I saw, on a TY program, How the Universe Works, that the moon is possibly hollow. Is that still being looked at? pass the ice cold one.

Most assuredly, the Moon is not hollow.

[orin stepanek]

FYI, you can edit your own posts to add corrections or clarifications!

Not if your not a member.

I've noticed that quite a few post as guests quite often! You might as well become a member; it's a nice forum and the members are nice! Please join!

[Ann]

EuropaJupiter_Voyager_960.jpg
To me, the red spot on this photo looks like a hole opening deep into Jupiter!

Maybe you're right!

Eli Galanti wrote:

Jupiter's Great Red Spot (GRS) is the most dominant and long-lived feature in Jupiter's atmosphere. However, whether this is a shallow atmospheric feature or a deeply rooted vortex has remained an open question. The recent gravity measurements, performed by the Juno mission, enabled the analysis of Jupiter's zonal flows that were found to penetrate to a depth of 3,000km below the cloud-level.

Ann

[neufer]

Click to play embedded YouTube video.

To me, the red spot on this photo looks like a hole opening deep into Jupiter!

Jupiter's Great Red Spot (GRS) is the most dominant and long-lived feature in Jupiter's atmosphere. However, whether this is a shallow atmospheric feature or a deeply rooted vortex has remained an open question. The recent gravity measurements, performed by the Juno mission, enabled the analysis of Jupiter's zonal flows that were found to penetrate to a depth of 3,000km below the cloud-level.

[heehaw]

https://www.nasa.gov/press-release/godd ... moonquakes

[Rafa Ruiz]

When were these pictures taken by the probe?

[bystander]

When were these pictures taken by the probe?

March 1979