Archives » Astronomy

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.)

The Sound of Dark Matter?

This is an oddity. From You Tube via Astronomy Picture of the Day for 16/12/20.

It’s a sonified image of the Bullet Cluster with low tones assigned to Dark Matter, mid-range to visible light and higher tones to X-rays.

It may be though that Dark Matter does not exist, as this post from the Daily Galaxy argues.

Collapse of Arecibo Telescope

The Arecibo Telescope was the largest single-dish radio telescope in the world for over 50 years. Among its achievements in Astronomy it has been used to measure the spin of Mercury, map the surface of Venus, discover the first planets outside our Solar System, verify the existence of gravitational radiation and search for extraterrestrial intelligence, but it seems it was first built for military purposes.

While being decommissioned the structure had a total collapse early this month.

The collapse was captured on video:-

Sampling an Asteroid

This is an animated sequence from You Tube via Astronomy Picture of the Day for 3/11/20 showing the OSIRIS-REx spacecraft touching – and lifting up part of – the surface of asteroid Bennu.

The plan is to return the sample to Earth for analysis with an eye to determining conditions in the early Solar System and whether the astreroid contains unusual minerals.

UGC 810

What a gem this is. Another from the Hubble telescope via Astronomy Picture of the Day for 18/10/20.

This is galaxy UGC 810. Its odd shape is because it is in collision with UGC 1813 (out of picture below the frame.) Altogether the configuration is known as Arp 273. See previous photo here.

UGC 810

Asteroid Bennu

This is from You Tube via Astronomy Picture of the Day for 12/12/20.

A video of Asteroid Bennu, first of all with speeded up spin, then zooming in to a prominent rock on the surface (given the name Simurgh apparently,) as shot from spacecraft OSIRIS-REx shortly to try to land and get a sample of Bennu to bring back to Earth.

It’s still thrilling to me that we as a species can do and see things like this.

G W Orionis

The Universe is a varied – and at times weird – place.

All of our Solar System’s planets orbit more or less in the same plane – effectively as if on a disc.

G W Orionis is different, showing orbiting material in different planes – maybe because it has three stars at its centre.

This animation is from You Tube via Astronomy Picture of the Day for 29/9/20:-

Where Elements Come From

I just love this.

Then again, as a chemist you would expect me to.

I got to this Periodic Table via Astronomy Picture of the Day (APOD) for 9/8/20. It shows the origins of the chemical elements as percentages of how the total number of each elements’ atoms were formed.

Periodic Table of Elements' Origins

Those parts in blue were formed in the Big Bang or by nuclear fusion in stars, green came from dying low mass stars, pink from cosmic ray fission, yellow from the explosions of massive stars, purple from neutron stars merging, light grey in exploding white dwarf stars.

There are areas of darker gray. The elements these refer to are mostly not found naturally – Technetium (Atomic Number 43,) Promethium (Atomic Number 61) and all the transuranics (Atomic Numbers greater than 92) can be made artificially in particle colliders or nuclear bombs and reactors, though I note that Neptunium (93) and Plutonium (94) seem to be produced by merging neutron stars. All elements with Atomic Numbers greater than 82 are radioactive and so decay away over time which is why the transuranics are not found on Earth and only some atoms of elements 82-92 are.

Quite why the version of this table that appears on APOD also has elements numbered 84-89 plus 91 in dark gray puzzles me a bit.

A Rocket Hovering

What a great photograph.

From Astronomy Picture of the Day for 25/7/20.

This is a Long March 5 heavy-lift rocket after taking off with its Tianwen-1 mission payload to Mars.

It looks like it’s hanging in mid-air.

Tianwen-1 in mid-air

free hit counter script