A Última Árvore (The Last Tree)
Mixed-media sculpture, Will Ferreira, 2013

I've changed the image in my page-top banner to a shot of Markarian's Chain. This group of galaxies is one of the most awe-inspiring sights I've had yet through an amateur telescope. I first viewed the chain in our back garden using my 150mm f8 refractor under the Bortle 4.5/5 skies we have here, and even in these less than ideal conditions, it looked wondrous.

It's not the size or brightness of the galaxies in the chain that's so jaw-dropping (they're rather faint in the eyepiece of a 6" refractor or 8" reflector), it's their number, coupled with the fact that with a low or medium power eyepiece you can see multiple galaxies in the field of view simultaneously. The chain and the Virgo cluster of which it is a part is probably the closest you can get, when using a small telescope, to the sort of galaxy-peppered views captured by the likes of Hubble and the James Web Space Telescope.

To view a single galaxy is mind-blowing enough, but being able to see several in same field of view is an experience for which you quickly run out of adjectives. To boot, being able to see the chain from a location as familiar as your own back garden just makes the experience feel all the more special.

So, if you're as relatively new to this as I am and you haven't yet pointed your scope at Markarian's chain, you really must put it on your shorlist of objects to see. It's quite something. For the majority of viewers in the northern hemisphere, the Virgo Cluster (the location of the chain) should be at its best between now and June.

So far I've only viewed the galaxies in the chain using my 150mm (6") refractor. I'm not sure how impressive the views are through scopes that gather less light, say, a 3" or 4" refractor. I'll get around to pointing my 100mm (4") refractor at the chain at some stage and will report back here with the results.

Links to articles about Markarian's Chain:

messier-objects.com
Wikipedia
Sky & Telescope

Markarian's Chain image courtesy of Hewholooks (Wikimedia Commons)

Following last month's decision by the International Union of Geological Sciences to reject the proposal to declare an Anthropocene epoch, I saw one or two comments on social media by environmental campaigners who seemed to regard the decision as a setback, even a defeat.

In the light of this, I was interested to read the following a couple of days back, in a paper published last year on the stratigraphic basis of the proposed epoch. This is from the introduction (the emphasis is mine and I've removed the inline references for readability):

"It is no longer necessary for every paper on the subject of the Anthropocene to summarize the case for the proposed new series/epoch and its suggested start in the mid-20th century, or to outline the whole history of the Anthropocene concept. Instead, this paper takes as its starting point recent work which reconfigures the Anthropocene from a proposed geological epoch to an emergent, unfolding, intensifying event. This work proposes that the Anthropocene concept would be most useful to science if it continues to be regarded as an informal time unit alongside the GTS."

Source: The stratigraphic basis of the Anthropocene Event

I have no expertise in the field, but I do like this approach, focusing not on the attempts at classification, but on the effects of recent human activity -- particularly on the effects of the Great Acceleration.

It reminded me of a twitter thread I read last year by Jacquelyn Gill, a palaeoecologist, who pointed out that we already have a geological epoch defined by humanity, namely, the Holocene, and that defining the Anthropocene as a formal geological epoch is not necessary for raising awareness about the profound global changes our activities are causing.

The World Wide Web turned 35 earlier this month. Tim Berners-Lee marked the day by posting an open letter:

Marking the Web’s 35th Birthday: An Open Letter

In it he urges users to work to protect the web from corporate control and to support projects that give users the tools to take control of and manage their own data.

Colour schemes for the Linux desktop and applications. The author highlights some really nice work.

My Top 3 Linux Color Schemes

The author also gives an honourable mention to Ethan Schoonover's venerable Solarized scheme. Solarized doesn't make it in to his top three, but only because he couldn't make it play nicely with the GTK themes he likes.

A fascinating and alarming interview in the Journal of Bibliophilic Design with Steve Tonkin, dark sky advisor to the Cranborne Chase National Landscape. Topics covered include the effects of light pollution on human health, on wildlife and biodiversity, and on the night sky and astronomy.

Right Light, Right Place, Right Time.

Disclosure: Steve is a member of my astronomy club, the Fordingbridge Astronomers.