This is of course not our own moon.

Titan, however has an atmosphere, itself murky at visible wavelengths of light but which would make its edges shimmery in any case, as pictured by the Cassini spacecraft above Saturn’s rings and clouds, showing off the hemisphere which Saturn never sees.

From Astronomy Picture of the Day for 27/5/22.

That sounds like a title from a 1960s or 70s SF story.

It isn’t though.

What was more or less theoretical then is real now.

And Sgr A* at the centre of the Milky Way has finally been photographed (well at radio wavelengths. The main image is composed of X-ray and infra-red data and spans 7 light years. By contrast the inset of the black hole’s surroundings is only ten light minutes across.)

No doubt you’ve already seen this but it’s worth posting anyway.

The picture is from Astronomy Picture of the Day for 13/5/22.

From Astronomy Picture of the Day for 8/5/22. A galaxy with rings.

This is spiral galaxy NGC 1512.

A striking resemblance to an eye.

From Astronomy Picture of the Day for 5/2/22 comes this dazzling apparition, variable star R Aquarii, actually a binary star, a cool red giant and hot white dwarf orbiting their overall centre of mass. Apparently with binoculars you can see the star vary in brightness obver about a year.

The image is a combination of visible (blue and red) and X-ray data (rendered in purple.)

These pictures from the widespread reaches of the Solar system continue to astonish me.

From Astronomy Picture of the Day for 28/11/21.

This is a photo of a kilometre high cliff – on Comet Churyumov-Gerasimenko. Taken by the Rosetta spacecraft.

It has a certain stark beauty.

Due to the comet’s low gravity you could jump off the cliff and likely survive.

Well, four of them.

From YouTube via Astronomy Picture of the Day for 30/11/21.

A time-lapse video of Uranus and its four largest moons Titania, Oberon, Umbriel and Ariel, captured by the Bayfordsbury Observatorybased in Hertfordshire, England. The whole sequence takes up four hours in real time.

The cross of the diffraction spike is an artefact of the telescope used.

The apparent movement of Uranus is actually due to the orbit of Earth round the sun, changing the angle of view. The diffraction spike’s rotation appears because of the rotation of the Earth.

Under certain conditions when the sun sets the very last colour that can be seen is green.

Such a sunset over the Ligurian Sea was captured by Paolo Lazzarotti in October, shown here first speeded up, then in real time and finally in slow motion.

(From You Tube via Astronomy Picture of the Day for 10/11/21.

The Sun is an unbelievably violent object. Not surprising given its temperature and the countless nuclear reactions taking place in its interior.

Sometimes this violence manifests itself in eruptions like the filament pictured below, which rose from the Sun last month.

(From You Tube via Astronomy Picture of the Day for 8/11/21.)

From NASA via Astronomy Picture of the Day for 13/8/21.

A beautiful spiral galaxy. The image shows emissions from hydrogen atoms, emphasising the reddish glow of the parts of the galaxy where stars are forming.

The galaxy looks slightly different in visible light.

This is from NASA via Astronomy Picture of the Day for 18/7/21.

The Andromeda Galaxy as seen in ultra-violet light. Compared to visible light images it really picks out the spiral arms but makes them look more like rings.