New Horizons: Approach Phase, OpsNav - 25 January 15 to 28 June 15 Options

[pioneer]

Could the albedo variations on Pluto be caused by clouds? I ask because Pluto does have an atmosphere though it is tenuous.

[Phil Stooke]

It's not just tenuous, it makes Mars look like Venus in comparison (post may not be 100% hyperbole-free). So no, not likely at all that real clouds could be present - thin atmospheric hazes maybe, probably only visible above the limb. These brightness variations are most likely to be variations in surface ice cover. But we explore because we don't know, so we could be surprised.

Phil

[TheAnt]

Oh there might not be any more atmospheric pressure than what was found at Triton. So no clouds, but as it is freezing out there should be some haze yes. But the cameras might not catch it since this ghost of an atmosphere is stirred by Charon and a whisp of it might even wrap also that largest satellite at times.

[Alan Stern]

Oh there might not be any more atmospheric pressure than what was found at Triton. So no clouds, but as it is freezing out there should be some haze yes. But the cameras might not catch it since this ghost of an atmosphere is stirred by Charon and a whisp of it might even wrap also that largest satellite at times.

Pluto's base atmospheric pressure is about like the Earth's mesopause....where noctilucent and polar mesospheric clouds form. I would not so quickly discount the possibility of condensation clouds and/or aerosol hazes-- we will see.

[Julius]

I recall the Uranus and Neptune flybys back in the 80 s. At the time I had to check any info from TV programmes covering the events and there weren't many. This day and age when you get social media and blogs It will be much easier to follow the Pluto flyby and the experience of such an encounter even more thrilling and exciting. Enjoy the ride. Thank you Alan Stern and NH team for this opportunity!

[TheAnt]

Pluto's base atmospheric pressure is about like the Earth's mesopause....where noctilucent and polar mesospheric clouds form. I would not so quickly discount the possibility of condensation clouds and/or aerosol hazes-- we will see.

Thank you for your correction Alan. And I should have known since I have indeed seen noctilucent clouds a number of times, and over the years even gotten some nice images of a few. Yet, I did not discount haze, we'll have to wait and see. =)

[ZLD]

Latest from yesterday.



Edit: Failed to disclose this image was processed with a histogram adjustment and a max entropy deconvolution process set to low impact.

[jgoldader]

Latest from yesterday.

Looks like we may be seeing albedo variations on Charon now. Wow. Wow!

[SFJCody]

So incredibly cool in every sense of the word...

I'm running Eyes On The Solar System 24/7 at the moment. Just fun to ride along and watch the distance tick down.

[scalbers]

Indeed any clouds/haze would have to be pretty optically thick to be so bright at this low of a phase angle. One might also compare what the atmospheric pressure is high up on Titan where the haze starts to become optically thick, as a rough analog.

Any chance that polar ice brightness could be enhanced by a slight sun glint effect? The geometry appears to be somewhat favorable if we consider a bi-directional reflectance function (BRDF).

[Habukaz]

Extended my latest Pluto/Charon raw image animations to include today's images; so now they go through 5-11 June, roughly covering one rotation for Pluto and Charon. The growth of Charon's apparent size is visible as the animation restarts, as is the acceleration of the growth of Pluto's apparent size.

[Habukaz]

New deconvolved images released. No word on Charon.

Down-scaled 4-frame version:

[Explorer1]

Media schedule is out now; quite busy!

http://www.nasa.gov/press-release/nasa-ann...for-pluto-flyby

For some reason that makes it even more real, that this is actually happening... time to dust off the ol' swear jar soon!

[Phil Stooke]

Here is a different processing of the deconvolved frames, greatly exaggerating brightness variations to show subtle features.

Phil

[ZLD]

So I'm confused about their animation. I see it and it appears that it rotates correctly as an animation but not like other images we've been seeing. Has this just been rotated to the right 90 degrees? It looks like, and they even annotate it as if NH is approaching Pluto right in its equatorial plane. Completely confused here.