Blue Skies of Pluto

On July 14, 2015 NASA’s New Horizons probe captured Pluto’s night-side illuminated by sunlight. Ponder blue skies of Pluto – not so different from planet Earth.

Blue sky phenomenon stems from small atmospheric particles scattering sunlight. Earthly particles are nitrogen molecules, on Pluto sootish little particles called tholins do the job. From –

“The term “tholin” was coined by Carl Sagan and Bishun Khare to describe organic substances they obtained in Miller-Urey experiments on gas mixtures akin to atmosphere of Saturn’s moon Titan. On Pluto, tholins form high in the atmosphere where UV sunlight breaks apart nitrogen and methane molecules. The fragments re-combine to form complex macromolecules. These macromolecules continue to combine and grow until they become “tholins.”

Nightside of Earth –

Tholins themselves aren’t blue, rather gray or red particles scattering sunlight. Science believes some of Pluto’s splotchy red surface comes from Tholin particles falling from the atmosphere.

Pluto – Up Close and Personal

Ponder Pluto up close and personal. A 380 kilometer wide portrait, immortalized on July 14, 2015 by New Horizons at a distance of 18,000 kilometers.

Text below taken from earthsky. –

New Horizons snapped the picture looking back at Pluto about 15 minutes after its closest approach on July 14th. Backlit by the sun, Pluto’s rugged, icy mountains tower over a vast frozen plain extending to the horizon. The backlighting highlights more than a dozen layers of haze in Pluto’s tenuous but distended atmosphere.

The new pictures provide evidence for a remarkably Earth-like “hydrological” cycle on Pluto – but involving soft and exotic ices, including nitrogen, rather than water ice. There are signs of hazes, evaporation, precipitation, and flowing glaciers similar to the frozen streams on the margins of ice caps on Greenland and Antarctica.

New Pluto images wow scientists

New Horizons Live

Tomorrow morning at 7:49 am EDT, New Horizons will make her historic closest approach to Pluto. Linked below is a live feed from NASA. “Live” being relative in terms of imagery – with a delay of four and a half hours, it will be several days before Pluto is revealed up close and personal.

NASA has scheduled a news conference for 3 pm eastern to reveal New Horizon’s first photographs. Up until now, New Horizons images of Pluto came from LORRI (Long Range Reconnaissance Imager). Once New Horizons settles into close orbit, Ralph and Alice get to work. Named after Ralph and Alice Kramden on The Honeymooners, Alice sees the ultraviolet spectrum, Ralph in full colour.

New Horizons Nearing Pluto

In less than a week, July 14 dawns with New Horizons orbiting Pluto at 12,500 kilometers. One of New Horizons niftiest capabilities comes from LORRI – Long Range Reconnaissance Imager, a remarkable high definition camera.

Take a few minutes to watch this video from the National Space Society.

This image of Pluto from New Horizons’ Long Range Reconnaissance Imager (LORRI) was received on July 8. This view is centered roughly on the area that will be seen close-up during New Horizons’ July 14 closest approach. This side of Pluto is dominated by three broad regions of varying brightness. Most prominent are an elongated dark feature at the equator, informally known as “the whale,” and a large heart-shaped bright area measuring some 1,200 miles (2,000 kilometers) across on the right. Above those features is a polar region that is intermediate in brightness. Image credit: NASA-JHUAPL-SWRI

Image taken on July 7 at a distance of 8 million kilometers by LORRI. When New Horizons reaches closest orbit on July 14, resolution will be 500 times clearer. Of interest are the elongated dark spot (dubbed – the whale) and heart shaped bright spot. This is the same view New Horizons will concentrate efforts on July 14. The “whale” measures 3000 kilometers, the “bright spot”, roughly 1,200 kilometers across.

From –

“The elongated dark area informally known as “the whale,” along the equator on the left side of the map, is one of the darkest regions visible to New Horizons. It measures some 1,860 miles (3,000 kilometers) in length.

Directly to the right of the whale’s “head” is the brightest region visible on the planet, which is roughly 990 miles (1,600 kilometers) across. This may be a region where relatively fresh deposits of frost—perhaps including frozen methane, nitrogen and/or carbon monoxide—form a bright coating.

Continuing to the right, along the equator, we see the four mysterious dark spots that have so intrigued the world, each of which is hundreds of miles across. Meanwhile, the whale’s “tail,” at the left end of the dark feature, cradles a bright donut-shaped feature about 200 miles (350 kilometers) across. At first glance it resembles circular features seen elsewhere in the solar system, from impact craters to volcanoes. But scientists are holding off on making any interpretation of this and other features on Pluto until more detailed images are in hand.”

Ponder New Horizons, a little probe nine years and five billion kilometers from Earth, traveling at 49,600 Kph., about to settle into orbit 12,500 kilometers above Pluto. If that doesn’t raise your holy crap meter, nothing will.