APOD: Pluto at Night (2022 Mar 26)

[APOD Robot]

Pluto at Night

Explanation: The night side of Pluto spans this shadowy scene. In the stunning spacebased perspective the Sun is 4.9 billion kilometers (almost 4.5 light-hours) behind the dim and distant world. It was captured by far flung New Horizons in July of 2015 when the spacecraft was at a range of some 21,000 kilometers from Pluto, about 19 minutes after its closest approach. A denizen of the Kuiper Belt in dramatic silhouette, the image also reveals Pluto's tenuous, surprisingly complex layers of hazy atmosphere. Near the top of the frame the crescent twilight landscape includes southern areas of nitrogen ice plains now formally known as Sputnik Planitia and rugged mountains of water-ice in the Norgay Montes.

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[Ann]

Please note that Pluto's atmosphere is blue!

Blue haze bands in Pluto's atmosphere. NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

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Departure shot of Pluto by New Horizons, showing Pluto's atmosphere backlit by the Sun. The blue color is close to what a human eye would have seen, and is caused by layers of haze in the atmosphere. NASA/JHUAPL/SwRI

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I would guess that Pluto's extremely thin atmosphere is blue for approximately the same reason that the Earth's skies are blue - it's because of the way sunlight is scattered in our respective atmospheres.

Of course, Pluto is more amazing because of its surface features than for its atmosphere. I find this quite jaw-droppingly stunning:

High resolution LORRI mosaic of a convecting region of Sputnik Planitia (context), up to its northwestern 'shoreline' (released 7 January 2016). Note isolated quadruple cell junction at lower right.

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To say that this landscape is out of this world doesn't doesn't even begin to do it justice. Note the little "cars" driving along the "highways", although some have veered off the roads and are stuck in the wilderness.

Ann

[AVAO]

...Of course, Pluto is more amazing because of its surface features than for its atmosphere. I find this quite jaw-droppingly stunning:

Ann

I also like turtle shells...

New Horizons' Very Best View of Pluto (movie)
https://photojournal.jpl.nasa.gov/archi ... c1080p.mp4
maybe the cars are also holes - or have sunk in the holes


https://live.staticflickr.com/65535/519 ... 7d92_b.jpg

https://live.staticflickr.com/65535/519 ... fa51_k.jpg

Earth today in comparison ...
https://live.staticflickr.com/65535/519 ... 2436_k.jpg
Jac Berne (flickr)

[madtom1999]

Are those actually layers in the atmosphere or are they digital features?

[AVAO]

Are those actually layers in the atmosphere or are they digital features?

I think the graphic inconsistencies are due to the time-shifted images of the corresponding satellites. You can also compare it yourself between google earth and nullschool. You just have to make sure that you choose the same "flight level" at nullschool and google earth:
https://earth.nullschool.net/#current/p ... .199,7.818
https://earth.google.com/web/@-82.43329 ... 877h,0t,0r

A live comparison between the polar vortices of the earth and jupiter would also be quite exciting. Maybe google and nasa could work together to that topic in the future

[orin stepanek]

Please note that Pluto's atmosphere is blue!

Blue haze bands in Pluto's atmosphere. NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

---

Departure shot of Pluto by New Horizons, showing Pluto's atmosphere backlit by the Sun. The blue color is close to what a human eye would have seen, and is caused by layers of haze in the atmosphere. NASA/JHUAPL/SwRI

---

I would guess that Pluto's extremely thin atmosphere is blue for approximately the same reason that the Earth's skies are blue - it's because of the way sunlight is scattered in our respective atmospheres.

Of course, Pluto is more amazing because of its surface features than for its atmosphere. I find this quite jaw-droppingly stunning:

High resolution LORRI mosaic of a convecting region of Sputnik Planitia (context), up to its northwestern 'shoreline' (released 7 January 2016). Note isolated quadruple cell junction at lower right.

---

To say that this landscape is out of this world doesn't describe its magnificent desolate beauty at all. Note the little "cars" diving along the "highways", although some have veered off the roads and are stuck in the wilderness.

Ann

They do look like roads; don't they?

[orin stepanek]

The little kid in the solar system! Gotta love her!

[E Fish]

Every time I see a picture of Pluto, I'm blown away by it. I grew up with Pluto being mostly a big question mark and I never thought that would change. To see these up close images is just so amazing. I'm taking my students on a tour of the solar system next week and I always show the pictures we had of Pluto before the New Horizons mission before I show them the amazing images after because I want them to appreciate just how much more we know now.

[johnnydeep]

Are those actually layers in the atmosphere or are they digital features?

I think the graphic inconsistencies are due to the time-shifted images of the corresponding satellites. You can also compare it yourself between google earth and nullschool. You just have to make sure that you choose the same "flight level" at nullschool and google earth:
https://earth.nullschool.net/#current/p ... .199,7.818
https://earth.google.com/web/@-82.43329 ... 877h,0t,0r

A live comparison between the polar vortices of the earth and jupiter would also be quite exciting. Maybe google and nasa could work together to that topic in the future

Not sure what you mean here. That those aren't actually visibly separated layers in Pluto's atmosphere? And as for "time shifted images of the corresponding satellites", there was only one fast flying probe taking the picture!

[Chris Peterson]

Are those actually layers in the atmosphere or are they digital features?

The layers are real. We're seeing dust distributed vertically into layers by gravity waves.

[AVAO]

Are those actually layers in the atmosphere or are they digital features?

The layers are real. We're seeing dust distributed vertically into layers by gravity waves.

That's correct. my answer was not related to the APOD main picture of Pluto.
Sorry for the confusion...

In the picture of Pluto, atmospheric layers can be seen.
The answer from chris is therefore correct.


The phenomenon of "gravitational waves" and their causes seems a bit hypothetical to me.

"Stern, who is associate vice president of R&D at the Southwest Research Institute (SwRI) in Colorado, spoke about the gravity-wave hypothesis at the Lunar and Planetary Science meeting in The Woodlands, Texas, in March. He said the conclusion that the bands are gravity waves is based on observations made by New Horizons, combined with computer simulations."
https://www.space.com/32778-pluto-hazy- ... waves.html

Alternatively, it would also make sense to me, if the layers resulted from the changes in chemical composition and different physical conditions (pressure, temperature, etc.) ...

[Chris Peterson]

Are those actually layers in the atmosphere or are they digital features?

The layers are real. We're seeing dust distributed vertically into layers by gravity waves.

That's correct. my answer was not related to the APOD main picture of Pluto.
Sorry for the confusion...

In the picture of Pluto, atmospheric layers can be seen.
The answer from chris is therefore correct.


The phenomenon of "gravitational waves" and their causes seems a bit hypothetical to me.

"Stern, who is associate vice president of R&D at the Southwest Research Institute (SwRI) in Colorado, spoke about the gravity-wave hypothesis at the Lunar and Planetary Science meeting in The Woodlands, Texas, in March. He said the conclusion that the bands are gravity waves is based on observations made by New Horizons, combined with computer simulations."
https://www.space.com/32778-pluto-hazy- ... waves.html

Alternatively, it would also make sense to me, if the layers resulted from the changes in chemical composition and different physical conditions (pressure, temperature, etc.) ...

Gravity waves. Gravitational waves are entirely different things. Note that the measurements of atmospheric temperature, pressure, and chemical composition show very smooth gradients, no discontinuities. So if the layering of dust is dependent on that, the mechanism is subtle.

I would also note that the core of most modern science is simulations. When a simulation matches an observation, that is taken as strong supportive evidence that the system under study is accurately modeled.

[AVAO]

The layers are real. We're seeing dust distributed vertically into layers by gravity waves.

That's correct. my answer was not related to the APOD main picture of Pluto.
Sorry for the confusion...

In the picture of Pluto, atmospheric layers can be seen.
The answer from chris is therefore correct.


The phenomenon of "gravitational waves" and their causes seems a bit hypothetical to me.

"Stern, who is associate vice president of R&D at the Southwest Research Institute (SwRI) in Colorado, spoke about the gravity-wave hypothesis at the Lunar and Planetary Science meeting in The Woodlands, Texas, in March. He said the conclusion that the bands are gravity waves is based on observations made by New Horizons, combined with computer simulations."
https://www.space.com/32778-pluto-hazy- ... waves.html

Alternatively, it would also make sense to me, if the layers resulted from the changes in chemical composition and different physical conditions (pressure, temperature, etc.) ...

Gravity waves. Gravitational waves are entirely different things. Note that the measurements of atmospheric temperature, pressure, and chemical composition show very smooth gradients, no discontinuities. So if the layering of dust is dependent on that, the mechanism is subtle.

I would also note that the core of most modern science is simulations. When a simulation matches an observation, that is taken as strong supportive evidence that the system under study is accurately modeled.

"I would also note that the core of most modern science is simulations. When a simulation matches an observation, that is taken as strong supportive evidence that the system under study is accurately modeled."

Yes, indeed! this is certainly right.
Thanks to you Chris, for your detailed feedback.

[Ann]

Gravity waves. Gravitational waves are entirely different things. Note that the measurements of atmospheric temperature, pressure, and chemical composition show very smooth gradients, no discontinuities. So if the layering of dust is dependent on that, the mechanism is subtle.

I would also note that the core of most modern science is simulations. When a simulation matches an observation, that is taken as strong supportive evidence that the system under study is accurately modeled.

ligo.caltech.edu wrote:

Gravitational waves are ripples in space-time (the fabled “fabric” of the Universe) caused by massive objects moving with extreme accelerations. In outer space that means objects like neutron stars or black holes orbiting around each other at ever increasing rates, or stars that blow themselves up.

Google(?) summarized a text from https://www.weather.gov like this:

A gravity wave is nothing more than a wave moving through a stable layer of the atmosphere. Thunderstorm updrafts will produce gravity waves as they try to punch into the tropopause. The tropopause represents a region of very stable air.

So gravitational waves are ripples in spacetime itself, but gravity waves are a certain kind of waves in a planet's atmosphere.

Ann