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  • Wednesday, 24th April 2024

    The Earthrise Story

    "Colour photograph of the Earth rising above the Moon's horizon. Taken during the Apollo 8 mission, 1968"

    I stumbled across the official story behind the famous "Earthrise" photograph taken during the Apollo 8 mission in 1968. Not only was it humanity’s first view of Earth from another planetary body, but it also played an important role in the growing environmental awareness in the late 1960s and '70s. The image was used as the cover photograph for the Spring 1969 issue of the Whole Earth Catalog and US Nature photographer Galen Rowell later described it as "the most influential environmental photograph ever taken". [¹][²]

    The Wikipedia entry contains additional information, including interesting details about the camera and film development process used as well as the image's impact and legacy.

    Fifty years later, Bill Anders, the astronaut who took the photograph, observed "We set out to explore the moon and instead discovered the Earth."

  • Tuesday, 9th April 2024

    Surveillance as a Service

    Technologies and tools that further erode citizens' privacy and ability to organise, protest, dissent and to engage in civil disobedience.

    Surveillance as a Service: The Global Impact of Israeli “Defense” Technologies on Privacy and Human Rights

  • Monday, 8th April 2024

    A Última Árvore (The Last Tree)

    Will Ferreira, 2013. Mixed media sculpture of a transhumanoid breathing precious clean air through a mask connected to a glass bottle containing the last tree on Earth

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

  • Friday, 5th April 2024

    Markarian's Chain

    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)

  • Tuesday, 2nd April 2024

    The Anthropocene: an event not an epoch

    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.

  • Wednesday, 27th March 2024

    ICYMI: The Web turned 35 this month

    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.

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