Category Archives: Science

Behold: the Andromeda galaxy, NGC 224 aka Messier 31 – our closest galactic neighbour, before and after image ‘cleanup’. To wit:

The picture is a stack of 223 images, each a 300 second exposure, taken from a garden observatory in Portugal over the past year. Obvious image deficiencies include bright parallel airplane trails, long and continuous satellite trails, short cosmic ray streaks, and bad pixels. These imperfections were actually not removed with Photoshop specifically, but rather greatly reduced with a series of computer software packages that included Astro Pixel Processor, DeepSkyStacker, and PixInsight. All of this work was done not to deceive you with a digital fantasy that has little to do with the real likeness of the Andromeda galaxy (M31), but to minimise Earthly artefacts that have nothing to do with the distant galaxy and so better recreate what M31 really does look like.

(ImageKees Scherer)

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Why, they’re luminous spheres of plasma held together by their own gravity.

Behold: NGC 290 – an extremely photogenic open cluster captured in 2006 by the Hubble Space Telescope. To wit:

Open clusters of stars are younger, contain few stars, and contain a much higher fraction of blue stars than do globular clusters of stars. NGC 290 lies about 200,000 light-years distant in a neighbouring galaxy called the Small Cloud of Magellan (SMC). The open cluster contains hundreds of stars and spans about 65 light years across. NGC 290 and other open clusters are good laboratories for studying how stars of different masses evolve, since all the open cluster’s stars were born at about the same time.

(ImageNASAESAHubble; Acknowledgement: E. Olzewski (U. Arizona))

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A sobering collaboration between the International Red Cross and our favourite German educational design studio Kurzgesagt. To wit:

Until we did the research. It turned out we were a bit oblivious off the real impact of nuclear weapons in the real world, on a real city. And especially, how helpless even the most developed nations on earth would be if an attack occurred today.

Previously: Argie Bargie

Behold: a very unusual form of large-scale electrical discharge known as red sprite – never before photographed at this level of detail. To wit:

Even though sprites have been recorded for over 30 years, their root cause remains unknown. Some thunderstorms have them, but most don’t. These mysterious bursts of light in the upper atmosphere momentarily resemble gigantic jellyfish. A few years ago high speed videos were taken detailing how red sprites actually develop. The featured image was captured last month in high definition from Italy. One unusual feature of sprites is that they are relatively cold — they operate more like long fluorescent light tubes than hot compact light bulbs. In general, red sprites take only a fraction of a second to occur and are best seen when powerful thunderstorms are visible from the side.

(ImageStephane Vetter (TWAN))

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Pity poor NGC 7714: a galaxy stretched and distorted by a recent collision with neighbouring galaxy NGC 7715. To wit:

This smaller neighbour, NGC 7715, situated off to the left of the featured frame, is thought to have charged right through NGC 7714. Observations indicate that the golden ring pictured is composed of millions of older Sun-like stars that are likely co-moving with the interior bluer stars. In contrast, the bright centre of NGC 7714 appears to be undergoing a burst of new star formation. The featured image was captured by the Hubble Space Telescope. NGC 7714 is located about 130 million light years away toward the constellation of the Two Fish (Pisces). The interactions between these galaxies likely started about 150 million years ago and should continue for several hundred million years more, after which a single central galaxy may result.

(Image: NASAESAHubble Legacy Archive)

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Behold: the Horsehead Nebula – the most famous (and beloved) interstellar cloud in the sky. To wit:

It is visible as the dark indentation to the red emission nebula in the centre of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula. Like clouds in Earth’s atmosphere, this cosmic cloud has assumed a recognisable shape by chance. After many thousands of years, the internal motions of the cloud will surely alter its appearance. The emission nebula‘s red colour is caused by electrons recombining with protons to form hydrogen atoms. On the image left is the Flame Nebula, an orange-tinged nebula that also contains filaments of dark dust. Just to the lower left of the Horsehead nebula featured picture is a blueish reflection nebulae that preferentially reflects the blue light from nearby stars.

(Image: José Jiménez Priego)

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Behold: the splendid spiral galaxy M33 – a trifling 3 million light years away, it’s also known as the Triangulum Galaxy. To wit:

The galaxy’s inner 30,000 light-years or so are shown in this magnificent 25 panel telescopic mosaic. Based on image data from space and ground-based telescopes, the portrait of M33 shows off the galaxy’s reddish ionised hydrogen clouds or HII regions. Sprawling along loose spiral arms that wind toward the core, M33’s giant HII regions are some of the largest known stellar nurseries, sites of the formation of short-lived but very massive stars. Intense ultraviolet radiation from the luminous, massive stars ionises the surrounding hydrogen gas and ultimately produces the characteristic red glow. To enhance this image, broadband data were used to produce a colour view of the galaxy and combined with narrowband data recorded through a hydrogen-alpha filter. That filter transmits the light of the strongest visible hydrogen emission line.

Huge image here (caution: you will tend to feel insignificant in the Grand Scheme.)

(Image: Subaru Telescope (NAOJ), Hubble Space Telescope – Image Processing: Robert Gendler. Additional Data: BYU, Robert Gendler, Johannes Schedler, Adam Block – Copyright: Robert Gendler, Subaru Telescope, NAOJ)

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NASA Goddard explains:

Have you ever thought about visiting a black hole? We sure hope not. However, if you’re absolutely convinced that a black hole is your ideal vacation spot, watch this video before you blast off to learn more about them and (more importantly) how to stay safe.

Download your safety brochure here.

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Behold; MyCn18, also known as the Engraved Hourglass Planetary Nebula.

Clearly seen at last, thanks to improved imaging techniques developed since it was first observed in the early decades of the 20th century . But who’s watching who exactly? To wit:

…the sands of time are running out for the central star of this hourglass-shaped planetary nebula. With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star’s life occurs as its outer layers are ejected – its core becoming a cooling, fading white dwarf. In 1995, astronomers used the Hubble Space Telescope (HST) to make a series of images of planetary nebulae, including the one featured here. Pictured, delicate rings of colorful glowing gas (nitrogen-red, hydrogen-green, and oxygen-blue) outline the tenuous walls of the hourglass. The unprecedented sharpness of the Hubble images has revealed surprising details of the nebula ejection process that are helping to resolve the outstanding mysteries of the complex shapes and symmetries of planetary nebulas like MyCn 18.

(ImageNASAESAHubble; Processing & LicenseJudy Schmidt)

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