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A Celestial Necklace

From Astronomy Picture of the Day for 18/5/21.

This beautiful celestial apparition is known as the Necklace Nebula. It is a so-called planetary nebula. These are formed by gases thrown off by stars nearing the end of their lives. The Nebula Necklace’s “Diamonds” are knots of glowing gas.

The Necklace Nebula

Crescent of Earth

Only 24 people have ever had the chance to see a view like this – or photograph it. The 24 astronauts of the Apollo Programme who made it to the Moon and back.

From Astronomy Picture of the Day for 29/4/21, a digitally restored photograph of the whole of planet Earth from its nightside, the last picture of its kind so far to be taken by human hands.

Crescent of Earth

Star Shredding Animation

From You Tube via Astronomy Picture of the Day for 27/4/21.

An animation of a star being shredded by a black hole.

Ingenuity’s First Flight.

From You Tube via Astronomy Picture of the Day for 20/4/21.

Ingenuity’s first (short) flight through the Martian atmosphere as seen from the Perseverance rover.

Flying a Kite

Two kites have been flown in the past twenty four hours.

One of them was on another planet.

The other might as well have been.

These are the days of miracle and wonder.

But also of greed and thoughtlessness.

O tempora, o mores.

Four Moons in One Frame

With bonus rings.

Another great picture from the Cassini Probe, taken from Astronomy Picture of the Day for 4/4/2021.

Four Saturnian Moons

The most obvious moon is the bright Dione, hovering on the centre of the frame, with shadowy but much larger Titan in the background. Titan is the tenth largest object in the Solar System bigger than the planet Mercury.

To the extreme right of the rings is Pandora, a moon which shepherds Saturn’s F ring.

Just in the gap in the rings (the Encke gap) is Pan, only 35 kilometres across but which keeps the gap free of ring particles.

Eyeball this Nebula

I found this (copyrighted) image on Astronomy Picture of the Day for 18/1/21.

The text on APOD’s post refers to it as looking like a brain – hence its name, the Medulla Nebula.

To me, though, it looks more like an eyeball – with the optic nerve going off to the right as in the diagram below.

eyeball

Mountains on Pluto

Remember those days when Pluto was just a blip on a photographic plate, then merely a fuzzy set of dots on a Hubble telescope image?

No more.

Astronomy Picture of the Day for 15/1/21 featured this photo taken by the New Horizons probe 15 minutes after its closest approach to the (dwarf) planet when it was 18,000 kilometres away from the surface.

Some of the mountains on show are comparable in height to the highest on Earth but of course they are not composed of rock but most likely of ice. The plains below them may contain solid nitrogen or carbon dioxide.

Also visible above Pluto’s horizon is its tenuous atmosphere.

Pluto's Mountains

The Hidden Face of Titan

From Astronomy Picture of the Day for 9/1/21 here is a view of Saturn’s moon Tiatn that you would never see if you were somehow be able to be on Saturn itself.

Titan is tide-locked to its primary and so always presents the same face to it. Its reverse side however was however visible to the Cassini probe.

Since Titan has an atmosphere its surface is not seen directly but the fuzziness around its edges – seen against the thick line of Saturn’s rings and the planet itself beyond – shows the atmosphere’s thickness relative to the satellite.

Titan from Cassini

Spectacular Aurora

On Astronomy Picture of the Day (APOD) for 3/1/21 there is a picture taken by Hallgrimur P Helgason, showing a great example of pareidolia (the tendency of humans to perceive a pattern that is not there.)

As it isn’t copyright free I’m not displaying it here but this is the link.

It’s a wonderful shimmering green-aura’d image of a flying bird which APOD likens to a phoenix (itself of course non-existent.)

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