Neptune ♡

Wide-Field Ellipse

The Big Dipper

by: VegaStar Carpentier

Comet Lovejoy (C/2014 Q2) by: Troy Casswell

This is a photo of the small island of Litla Dimun which is situated between Suouroy and Stora Dimun in the Faroe Islands. It is the smallest of the Islands being less than 100 hectares (250 acres) in size and it is uninhabited. The island is often covered by lenticular clouds. Lenticular clouds, also known as altocumular standing lenticularis clouds, are formed when a current of moist air is forced upwards as it travels over elevated land. This elevation and subsequent decrease in temperature causes the moisture in the air to condense and form a cloud. Lenticular clouds appear to be perfectly stationary but in fact this is not the case. These clouds only appear stationary because the flow of moist air continually resupplies the cloud from the windward side even as water evaporates and vanishes from the leeward side. Lenticular clouds can look like they are hovering for hours or days, until the wind or weather changes and the clouds disperse. They also look like a hat! -Jean Photo courtesy of Caters news agency.

Known as the Horsehead Nebula – but you can call it Starbiscuit.

Found by our Hubble Space Telescope, this beauty is part of a much larger complex in the constellation Orion.

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2019 October 17

Moons of Saturn Image Credit: Cassini Imaging Team, SSI, JPL, NASA

Explanation: On July 29, 2011 the Cassini spacecraft’s narrow-angle camera took this snapshot and captured 5 of Saturn’s moons, from just above the ringplane. Left to right are small moons Janus and Pandora respectively 179 and 81 kilometers across, shiny 504 kilometer diameter Enceladus, and Mimas, 396 kilometers across, seen just next to Rhea. Cut off by the right edge of the frame, Rhea is Saturn’s second largest moon at 1,528 kilometers across. So how many moons does Saturn have? Twenty new found outer satellites bring its total to 82 known moons, and since Jupiter’s moon total stands at 79, Saturn is the Solar System’s new moon king. The newly announced Saturnian satellites are all very small, 5 kilometers or so in diameter, and most are in retrograde orbits inclined to Saturn’s ringplane. You can help name Saturn’s new moons, but you should understand the rules. Hint: A knowledge of Norse, Inuit, and Gallic mythology will help.

∞ Source: apod.nasa.gov/apod/ap191017.html

Sprite (lightning)

Sprites or red sprites are large-scale electrical discharges that occur high above thunderstorm clouds, or cumulonimbus, giving rise to a quite varied range of visual shapes flickering in the night sky. They are usually triggered by the discharges of positive lightning between an underlying thundercloud and the ground.

Sprites appear as luminous reddish-orange flashes. They often occur in clusters above the troposphere at an altitude range of 50–90 km (31–56 mi). Sporadic visual reports of sprites go back at least to 1886, but they were first photographed on July 6, 1989 by scientists from the University of Minnesota and have subsequently been captured in video recordings many thousands of times.

Sprites are sometimes inaccurately called upper-atmospheric lightning. However, sprites are cold plasma phenomena that lack the hot channel temperatures of tropospheric lightning, so they are more akin to fluorescent tube discharges than to lightning discharges. source, images