Category Archives: Science

Sorry – must’ve been that lentil dahl.

Behold: Messier 82, aka the Cigar Galaxy, smoking away like it had some kind of infinite gas reservoir – fooling no one but itself. To wit:

M82, as this starburst galaxy is also known, was stirred up by a recent pass near large spiral galaxy M81. This doesn’t fully explain the source of the red-glowing outwardly expanding gas and dust, however. Evidence indicates that this gas and dust is being driven out by the combined emerging particle winds of many stars, together creating a galactic superwind. The dust particles are thought to originate in M82’s interstellar medium and are actually similar in size to particles in cigar smoke. The featured photographic mosaic highlights a specific colour of red light strongly emitted by ionised hydrogen gas, showing detailed filaments of this gas and dust. The filaments extend for over 10,000 light years. The 12-million light-year distant Cigar Galaxy is the brightest galaxy in the sky in infrared light, and can be seen in visible light with a small telescope towards the constellation of the Great Bear (Ursa Major).

(ImageNASAESAHubbleDaniel Nobre)

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Last week’s full moon or Buck Moon (captured during its partial eclipse by Cristian Fattinnanzi) was very full. How full, you ask?

…it fell almost exactly in a line with the Sun and the Earth. When that happens the Earth casts its shadow onto the Moon. The circularity of the Earth’s shadow on the Moon was commented on by Aristotle and so has been noticed since at least the 4th century BC. What’s new is humanity’s ability to record this shadow with such high dynamic range (HDR).

The featured HDR composite of last week’s partial lunar eclipse combines 15 images and includes an exposure as short as 1/400th of a second — so as not to overexpose the brightest part — and an exposure that lasted five seconds — to bring up the dimmest part. This dimmest part — inside Earth’s umbra — is not completely dark because some light is refracted through the Earth’s atmosphereonto the Moon. A total lunar eclipse will occur next in 2021 May.

Giant image here.

UPDATE: a deliciously moony mashup from 2013.

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Aggh! It’s a TIE fighter. No wait, it’s a sunspot. No wait, it’s the International Space Station. But what’s it doing on the Sun? To wit:

Transiting the Sun is not very unusual for the ISS, which orbits the Earth about every 90 minutes, but getting one’s timing and equipment just right for a great image is rare. Strangely, besides that fake spot, in this recent two-image composite, the Sun lacked any real sunspots. The featured picture combines two images — one capturing the space station transiting the Sun — and another taken consecutively capturing details of the Sun’s surface. Sunspots have been rare on the Sun since the dawn of the current Solar Minimum, a period of low solar activity. For reasons not yet fully understood, the number of sunspots occurring during both the previous and current solar minima have been unusually low.

(Image: Rainee Colacurcio)

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Five days before this image was captured over Norway in 2012, a large coronal mass ejection occurred on the sun, throwing a cloud of fast moving electrons, protons, and ions toward the Earth. To wit:

Although most of this cloud passed above the Earth, some of it impacted our Earth’s magnetosphere and resulted in spectacular auroras being seen at high northern latitudes. Featured here is a particularly photogenic auroral corona captured above GrotfjordNorway. To some, this shimmering green glow of recombining atmospheric oxygen might appear as a large eagle, but feel free to share what it looks like to you. Although the Sun is near Solar Minimum, streams of the solar wind continue to impact the Earth and create impressive auroras visible even last week.

(Image: Bjørn Jørgensen)

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Behold: NGC 3242 – the cast off shroud of a dying sun-like star known as The Ghost Of Jupiter Nebula. To wit:

…this deep and wide telescopic view also finds the seldom seen outer halo of the beautiful planetary nebula at the upper left, toward Milky Way stars and background galaxies in the serpentine constellation Hydra. Intense and otherwise invisible ultraviolet radiation from the nebula’s central white dwarf star powers its illusive glow in visible light. In fact, planets of NGC 3242’s evolved white dwarf star may have contributed to the nebula’s symmetric features and shape. Activity beginning in the star’s red giant phase, long before it produced a planetary nebula, is likely the cause of the fainter more extensive halo. About a light-year across NGC 3242 is some 4,500 light-years away. The tenuous clouds of glowing material at the right could well be interstellar gas, by chance close enough to the NGC 3242’s white dwarf to be energized by its ultraviolet radiation.

(ImageCHART32 Team, Johannes Schedler / Volker Wendel)

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It’s very difficult to tell what’s going on at the centre of our galaxy, what with interstellar dust blocking the view of conventional telescopes. In other bands of light however, such as radio, it’s a pretty lively place. To wit:

The featured picture shows the inaugural image of the MeerKAT array of 64 radio dishes just completed in South Africa. Spanning four times the angular size of the Moon (2 degrees), the image is impressively vast, deep, and detailed. Many known sources are shown in clear detail, including many with a prefix of Sgr, since the Galactic Center is in the direction of the constellation Sagittarius. In our Galaxy’s Center lies Sgr A, found here just to the right of the image center, which houses the Milky Way’s central supermassive black hole. Other sources in the image are not as well understood, including the Arc, just to the left of Sgr A, and numerous filamentary threads. Goals for MeerKAT include searching for radio emission from neutral hydrogen emitted in a much younger universe and brief but distant radio flashes.

(Image: MeerKATSARAO)

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Behold NGC 1566 – also known as ‘The Spanish Dancer Spiral Galaxy’. To wit:

An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view. Classified as a grand design spiral, NGC 1566’s shows two prominent and graceful spiral arms that are traced by bright blue star clusters and dark cosmic dust lanes. Numerous Hubble Space Telescope images of NGC 1566 have been taken to study star formationsupernovas, and the spiral’s unusually active centre. Some of these images, stored online in the Hubble Legacy Archive, were freely downloaded, combined, and digitally processed by an industrious amateur to create the featured image. NGC 1566’s flaring centre makes the spiral one of the closest and brightest Seyfert galaxies, likely housing a central supermassive black hole wreaking havoc on surrounding stars and gas.

Full sized image here.

(ImageNASAESAHubbleLeo Shatz)

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Alas, now getting shorter again.

A composite image of the time between the Winter and (nearly) Summer Solstice (December 21, 2018 to June 16, 2019) all compressed into a single point of view. To wit:

 Dubbed a solargraph, the unconventional picture was recorded with a tall, tube-shaped pinhole camera using a piece of photographic paper. Fixed to a single spot at Casarano, Italy for the entire exposure, the simple camera continuously records the Sun’s daily path as a glowing trail burned into the photosensitive paper. Breaks and gaps in the trails are caused by cloud cover. At the end of the exposure, the paper was scanned to create the digital image. Of course, starting in December the Sun trails peak lower in the sky, near the northern hemisphere’s winter solstice. The trails climb higheras the days grow longer and the June 21st summer solstice approaches.

(Image: Gianluca Belgrado)

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Behold M83 (no, not the French electronica project): a beautiful spiral galaxy, 12 million lights years away on the southeastern tip of the constellation of Hydra (no, not the Marvel Universe terrorist organisation). In fact, Messier 83 –  its full title – has many names. To wit:

Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name, The Southern Pinwheel. But reddish star forming regions that dot the sweeping arms highlighted in this sparkling colour composite also suggest another nickname, The Thousand-Ruby Galaxy. About 40,000 light-years across, M83 is a member of a group of galaxies that includes active galaxy Centaurus A. In fact, the core of M83 itself is bright at x-ray energies, showing a high concentration of neutron stars and black holes left from an intense burst of star formation. This sharp composite colour image also features spiky foreground Milky Way stars and distant background galaxies. The image data was taken from the Subaru Telescope, the European Southern Observatory’s Wide Field Imager camera, and the Hubble Legacy Archive.

(Image: Subaru Telescope (NAOJ), Hubble Space TelescopeEuropean Southern Observatory, Robert Gendler)

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