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37 Articles

Going all deep and meaningful

READING THE ARTICLES in this issue about Williamina Fleming and E.E. Barnard, has made me reflect on how much we owe to these and other giants of the astronomy world, now long since gone. This holds true for all aspects of astrophysics — e.g. planetary studies, solar physics — but perhaps for none more so than the pioneers of the deep sky. Without their tireless efforts, our species would have had absolutely no clue about the nature, size and scale of our cosmos and where we fit into it. Just think — it’s not much more than 100 years ago that most astronomers believed that our Milky Way galaxy was the full extent of the universe. They had no idea that there were other galaxies beyond, nor were they even fully…

Going all deep and meaningful

Fomalhaut's planet-forming disk revealed

Continuing its run of ground-breaking discoveries, the James Webb Space Telescope (JWST) has snapped the clearest images yet of the dusty debris disk around Fomalhaut, a bright, young star 25 lightyears away in Piscis Austrinus. The images reach a resolution and sensitivity far beyond the capability of earlier instruments. András Gáspár (University of Arizona) and colleagues presented new details in this planet-forming disk on May 8 in Nature Astronomy. The team also included new Hubble Space Telescope images in their analysis. Previously, Hubble, the Spitzer Space Telescope and other telescopes had shown that Fomalhaut hosts a far-out ring of planet-forming debris that’s akin to the Kuiper Belt in our Solar System. Analysis of the system’s brightness at different wavelengths had also suggested the presence of a dusty inner disk analogous to the…

Fomalhaut's planet-forming disk revealed

Distorted galaxy hints at nature of dark matter

ASTRONOMERS HAVE PROVIDED the most direct evidence yet that dark matter does not consist of ultramassive particles. The work, based on supercomputer calculations, suggests that dark matter is instead made up of axions — hypothetical particles so light that they travel through space more like waves. If correct, the researchers’ conclusions would not only help reveal what 85% of matter in the universe is made of; the results could also lead to new physics beyond the standard model. The study was published April 20 in Nature Astronomy. Dark matter is tricky to investigate because it doesn’t emit, absorb or reflect light. So instead, a team led by graduate student Alfred Amruth (University of Hong Kong) looked for the material’s influence on gravitational lensing. In this effect, a galaxy and its dark matter…

Distorted galaxy hints at nature of dark matter

Meteorite crashed into New Jersey home When Suzy Kop stepped into her father’s bedroom on May 8, she saw a black, mango-size rock on the floor, its broken surface exposing a creamy interior. Looking around, she spotted two holes in the ceiling, and she knew something wasn’t right. Some 15 minutes before Kop had arrived (around 12:30pm), there was a report of a fireball in the area. As it happened, the heavy end of that falling star crashed through the roof of the home in Hopewell Township, New Jersey. The meteorite struck the floor with such force that it rebounded and punched a second hole in the ceiling before landing back on the floor. Unsure what to do, Kop called the Hopewell police for assistance. A hazmat team arrived to examine…

Mini-Neptune reveals (some of) its secrets

Astronomers armed with new James Webb Space telescope (JWST) images have gotten under the high-altitude skin of the mini-Neptune dubbed GJ 1214b. The results, published in Nature, suggest that this planet’s atmosphere is composed of some combination of water, methane and hydrogen cyanide, all wrapped thickly in highly reflective clouds or haze. GJ 1214b swings around its red dwarf star every 1½ days, so it’s scorchinghot. But it maintains an atmosphere, and from the world’s lightweight density, astronomers had suspected that water in some form would be a major constituent. But multiple attempts to take the atmosphere’s spectrum as the world passed in front of its star were stymied by what appeared to be highaltitude clouds or hazes. Now, JWST observations of the full orbit have enabled a team led by Eliza…

Mini-Neptune reveals (some of) its secrets

New moon discoveries put Saturn in the lead

Saturn has reclaimed the record for most moons in the Solar System with the discovery of 63 new moons. All are only a few kilometres in size and have orbits far from the planet. At the time of writing, the International Astronomical Union’s Minor Planet Center (MPC) has published the moons’ orbits in a series of Minor Planet Electronic Circulars issued between May 3 and 23. The new discoveries bring Saturn’s total moon count to 146, including 24 ‘regular’ moons, which formed around the planet, and 122 smaller, ‘irregular’ moons on elongated, and tilted orbits. The new reports more than double Saturn’s irregular moons and put Saturn far ahead of Jupiter’s 95 moons (which had put Jupiter in first place earlier this year). The torrent of Saturnian discoveries comes from a series…

New moon discoveries put Saturn in the lead

Solar activity ramps up but solar cycle still weak

THE SUN HAS been busy lately. Activity, including sunspots and flares, began picking up steam last year before suddenly ramping up even more in early 2023. The sudden rise prompted some to wonder if the current solar cycle is becoming more active than scientists had predicted. The Sun goes through 11-year cycles of magnetic activity during which its magnetic poles swap places. The last cycle (Cycle 24) was one of the quietest cycles on record, and the Solar Cycle Prediction Panel, an international group of experts, forecast that the current cycle (Cycle 25) would be on par with it or only slightly more active. Lisa Upton (Southwest Research Institute), co-chair of the panel for Cycle 25, holds that the current activity still matches the panel’s prediction. “It has been a decade since…

Solar activity ramps up but solar cycle still weak

Star caught swallowing a planet

The dinner bell has struck for a star in the constellation Aquila, the Eagle. Reporting in the May 4 issue of Nature, Kishalay De (MIT) and a team of astronomers watched the star belch and brighten in a way that suggests it swallowed a closely orbiting planet. The star in question is a Sun-like star about 13,000 light-years away. Pre-outburst observations indicate it was entering its golden years, a dangerous time for the planets it hosts. As the star finishes fusing the hydrogen in its core and swells, it may engulf the closest worlds — just as the Sun will one day do to Mercury, Venus and perhaps Earth. De was originally searching for brilliant blasts from white dwarfs when he stumbled on a seemingly ordinary star in Zwicky Transient Facility (ZTF)…

Star caught swallowing a planet

The epicycle and the equant

For many thousands of years, watchers of the night skies have noted points of light that look like stars and do not behave as other stars do. They shift their positions relative to the ‘fixed stars,’ which remain in the recognisable patterns we call constellations. To the Greek astronomers of 2,000 years ago, these ‘wandering stars,’ or planets, were five in number — Mercury, Venus, Mars, Jupiter and Saturn. To these they added the Sun and the Moon to make up seven such celestial objects, seven being a number with special significance. In seeking to explain how these bodies moved, and how their movements might be predicted (important for astrology), the Greeks were (mostly) agreed on two things: the Earth was the centre of the cosmos and everything else revolved around…

The epicycle and the equant

DAWN of the Milky Way

We live in a great galaxy, one that’s far larger and brighter than most others in the cosmos. Abounding with countless stars and surrounded by dozens of satellite galaxies, the Milky Way is a giant barred spiral with a dark matter halo spanning some 2 million light-years. Our galaxy’s disk is spinning so fast that we race along at more than 800,000 kilometres per hour as the Solar System speeds around the galactic centre. But how did this vast entity arise? Remarkable new discoveries, enabled by the Gaia spacecraft’s precise measurements of star positions and velocities, are providing incredible insights into the Milky Way’s earliest epochs. These observations reach all the way back to our galaxy’s initial chaotic state, when the Milky Way was smaller and just starting to assemble itself. Astronomers…

DAWN of the Milky Way

THE ALUMINIUM CLOCK

Aluminium can reveal which stars were born in fast-paced galaxies. Such galaxies quickly enrich themselves with carbon, nitrogen and oxygen as stellar winds and supernova explosions spew these elements into space; newborn stars then inherit the three elements, which catalyse the hydrogen-tohelium fusion reaction via the so-called CNO cycle. The CNO cycle also speeds up the production of aluminium, so the faster carbon, nitrogen and oxygen emerge from stars, the more aluminium arises too. The CNO cycle converts some of the carbon and oxygen a star is born with into nitrogen-14. Later in the star’s life, two helium-4 nuclei hit some of this nitrogen-14 and create neon-22, a neutron-rich isotope with 10 protons but 12 neutrons. Subsequent nuclear reactions with this neon cause some of those neutrons to end up in aluminium,…

THE ALUMINIUM CLOCK

Shake, rattle and roll

“My power’s really low, so this may be the last image I can send. Don’t worry about me though: my time here has been both productive and serene. If I can keep talking to my mission team, I will — but I’ll be signing off here soon. Thanks for staying with me.” This was the farewell message from @NASAInSight, the official Twitter account of NASA’s Insight lander. For four years, the spacecraft had studied the interior of Mars in an unprecedented way. But dust accumulating on the lander’s solar panels had been steadily reducing their power output, to the point that the craft was no longer able to charge its batteries. The image posted with the tweet looked like a car-crash scene from Mad Max, a fish-eye view of dustcovered gadgets…

Shake, rattle and roll

Williamina Fleming's deep sky discoveries

Many articles and books describe the rise to fame of maid-turned-astronomer Williamina ‘Mina’ Paton Fleming (1857–1911) and her contributions to stellar classification. But her deep sky discoveries may hold a few surprises. In 1879, after emigrating to Boston from Scotland, her husband abandoned her while she was expecting their son. Seeking employment, Fleming found it when Edward Charles Pickering, director of Harvard College Observatory (HCO), hired her as his second housekeeper. In the late 1870s, Pickering had initiated an ambitious program in stellar photometry (precise measurement of stars’ brightnesses) at HCO using a visual instrument he devised that he called a meridian photometer. During the day, an assistant would transcribe Pickering’s observing notes from the night before and then apply corrections to compute stellar magnitudes. Legend has it that the sloppy…

Williamina Fleming's deep sky discoveries

Snagging Planetary Nebulae

Most of Fleming’s planetaries are small — less than 15″ in diameter — with high surface brightnesses. As a result, you may need to use at least 200× before noticing a fuzzy glow. But how do you identify a stellar planetary at low power? That’s easy enough: by ‘blinking’ with an O III or narrowband filter (with a few exceptions). The planetary will appear to light up as the background sky darkens and the filter suppresses the nearby stars.…

Snagging Planetary Nebulae

E. E. Barnard and his Milky Way masterpiece

On February 6, 1923, American astronomer Edward Emerson Barnard lay dying in the upstairs bedroom of his house on the shore of Lake Geneva, Wisconsin, not far from the two telescopes he loved most — the 25cm (10-inch) Bruce astrograph he used extensively to photograph the Milky Way and the Yerkes 1m (40-inch) refractor, the world’s largest instrument of its kind. Few astronomers have achieved Barnard’s distinguished record. His name is forever tied to the eponymous Barnard’s Star in Ophiuchus and the nebulous Barnard’s Loop in Orion. He’s also famously known for his catalogue of 369 dark nebulae — some of which are among the most photogenic objects in the night sky. Perhaps Barnard’s greatest achievement, however, was his magnificent and monumental photographic tour de force, A Photographic Atlas of Selected…

E. E. Barnard and his Milky Way masterpiece

THE STRANGE ODYSSEY OF THE BRUCE ASTROGRAPH

Forty of the 50 plates included in Barnard’s monumental A Photographic Atlas of Selected Regions of the Milky Way were obtained with the Bruce astrograph at Mount Wilson in 1905. Afterwards, the instrument was returned to Yerkes Observatory and set up in a small dome between the main observatory building and Barnard’s house on the shore of Lake Geneva. Although the transparency at Yerkes was generally not as good as at Mount Wilson, Barnard did succeed in obtaining some excellent plates there. After Barnard’s death in 1923, Yerkes director Edwin Brant Frost hired Frank E. Ross, who moved into Barnard’s house. Ross was tasked with taking over Barnard’s program of Milky Way photography. He realised that by comparing recent plates with Barnard’s from 20 years earlier, he could find stars with…

THE STRANGE ODYSSEY OF THE BRUCE ASTROGRAPH

Hooray for Herman's Cross

Near the eastern border of Sagittarius, the Archer, you’ll find a neat little cross asterism formed by four 5th-magnitude stars: 59, 60, 62 and Omega (ω) Sagittarii. At 2° tall and 1° wide, the asterism is big enough to be spotted with the naked eye, and it makes a fun binocular target. Look for it about halfway between the 4th-magnitude star Psi (ψ) Capricorni and the Teapot of Sagittarius. In the Chinese constellations, this group of four stars is known as Gǒu Guó, or Dog Territory. The Alexandrian astronomer Ptolemy recorded it as the ‘Tetrapleuron,’ which means quadrilateral. In his 1603 Uranometria, Johann Bayer Latinised the Greek ‘Tetrapleuron’ to ‘Terebellum,’ and in 1801 Johann Bode included the Terebellum in his Uranographia atlas. Sometime thereafter astronomers stopped labelling it, at least in…

Hooray for Herman's Cross

USING THE STAR CHART

HOW Go outside within an hour or so of a time listed above. Hold the map out in front of you and turn it around so the label for the direction you’re facing (such as west or northeast) is right-side up. The curved edge represents the horizon, and the stars above it on the map now match the stars in front of you in the sky. The centre of the map is the zenith, the point in the sky directly overhead. FOR EXAMPLE Turn the map around so the label ‘Facing North’ is right-side up. About halfway from there to the map’s centre is the bright star Procyon. Go out and look north halfway between the horizon to straight overhead, and there you’ll find Procyon! NOTE The map is plotted for 35°…

USING THE STAR CHART

Southern Scorpius

Last issue I took a look at the northern half of the giant curl of bright stars that is Scorpius, the Scorpion. This time we’re going to dive down into the constellation’s southerly half — a region brimming with wonders. Let’s start our tour with the two bright and close stars that together form the tip of the Scorpion’s stinger: 1.6-magnitude Lambda (λ) Scorpii (Shaula) and 2.7-magnitude Upsilon (υ) Scorpii (Lesath). They’re sometimes known as the Cat’s Eyes, though one eye is much brighter than the other. Every winter I watch the pair’s progress across the sky, leading the way for Sagittarius. Shaula and Lesath are only 36′ apart; having two bright stars apparently so close together is very rare. Shaula is the 24th brightest star in all the heavens, falling…

Southern Scorpius

Two planets to observe at opposition

We have two planetary oppositions to cover this issue, plus the usual inner planet conjunctions as well as the southern spring equinox. Let’s start as we always do, with the innermost planet, Mercury (mag. 0.3, dia. 7.5˝, Aug. 10), which begins August in the western evening sky. Reaching greatest elongation (i.e. angle from the Sun) of 27° on the 10th, you’ll find that it has a companion — Mars, just 5° away — for about a week. (The colour contrast between the two will be quite noticeable, Mercury being white and Mars being a ruddy reddish hue.) After this, Mercury then heads for the horizon and reaches inferior conjunction (between the Earth and the Sun) on September 6. About a week later you’ll find it skimming the eastern horizon before dawn,…

Two planets to observe at opposition

Catching the tail end

The months of August and September are very light-on for meteor activity for southern observers. Our friends in the northern half of the planet are fortunate to be treated to the Perseids shower — which has its maximum on the morning in August 13 — but the radiant is so far north that very few of its meteors make their way far enough south of the celestial equator to be noticed by us. But all is not completely lost — in August we catch the tail end of the Southern Delta Aquariids shower, which reached its maximum on July 27 and remains somewhat active up until around to August 23. The same goes for the Piscis Austrinids, which reached maximum on July 29 and remains active until August 10. Don’t expect…

Catching the tail end

Comets on the rise

As winter changes into spring for the Southern Hemisphere, several comets should be within the range of small backyard telescopes. Receding from its perihelion of July 31 (1.48 AU) and perigee (0.54) on July 20, C/2021 T4 (Lemmon) will probably still glow softly at close to magnitude 10 in early August as it passes from Scorpius to Lupus and into Libra. By the end of the month, it is unlikely to be brighter than magnitude 11 to 11.5. Also glowing at about magnitude 10, C/2020 V2 (ZTF) will make its closest approach to Earth (1.86 AU) on September 17. The comet will begin August in Cetus, crossing to Eridanus around the middle of the month. It will cross into Cetus again during the first half of September before briefly visiting Fornax and…

Comets on the rise

The view through the window

A stronomers are nosey. We want to know if there are fish under the ice on Europa, and why Betelgeuse faded and then recovered. Or one of my favourites: What can we see through ‘Baade’s Window,’ the hole in the dust in the direction of the Galactic centre? This ‘window’ enables us to see to within 1,800 light-years of the core of our Milky Way galaxy, and Walter Baade used it to study RR Lyrae variables and determine the distance to the centre of the Galaxy to be 27,000 light-years, an estimate now refined to 26,000 light-years. Our star of interest in this issue, the bright Cepheid variable W Sagittarii, is 1,400 light-years distant, in the foreground of the Window. Cepheids are another type of star that have been used to…

The view through the window

Saturn at Opposition

WHETHER IT’S YOUR first time or 200th, Saturn is an irresistible telescopic sight. The planet brightens to magnitude +0.4 as it inches westward across central Aquarius this year. By opposition on August 27, its globe will span 19.0″ and the rings will extend to 43.1″. The most notable change compared to last year is the narrowing tilt of those rings. Tipped by just 9.0° at opposition, we view the north face of the rings. We’ll continue to do so until March 2025, when they will be presented edge-on. A 60mm telescope magnifying 40× will show the rings easily. Saturn’s diminishing tilt means it’s difficult to observe the entire curve of the dark Cassini Division, which separates the A and B rings. However, the gap should still be easy to make out…

Saturn at Opposition

Neptune at Opposition

THE BRIGHTEST PLANETS naturally get a lot of telescopic attention because most of them appear large enough to display interesting surface or atmospheric features. Neptune, on the other hand, is our Solar System’s most distant major planet and presents the tiniest disk, despite being four times larger than Earth. When it reaches opposition on September 19, it will be 4.3 billion km away and shine at magnitude 7.8. The ice giant looks like a field star at low magnification — albeit a blue-coloured one — due to the methane in its atmosphere, which absorbs red light. But a 15cm telescope and a magnification of around 150×, combined with good seeing, will turn this faint ‘star’ into a 2.4″-wide dot. Beyond that little else is visible, though experienced imagers occasionally tease…

Neptune at Opposition

A deep dive into NGC 6822

Edward Emerson Barnard is known today for a number of things. His photographic work is highly regarded, particularly his images published in 1927 in A Photographic Atlas of Selected Regions of the Milky Way. But he was also one of the most accomplished visual observers in history. Barnard’s discovery in 1892 of Jupiter’s fifth moon (which he denoted Jupiter V and which is now called Amalthea) was the first addition to the gas giant’s retinue since Galileo, and the last planetary satellite to be discovered visually. He also identified the star in Ophiuchus that possesses the highest proper motion (about 10″ per year). At a distance just shy of 6 light-years, Barnard’s Star, as we now know it, is second only to the Alpha Centauri system overall. In 1884 Barnard aimed…

A deep dive into NGC 6822

More suspense at Saturn

During the late 1970s the eagleeyed observer Stephen James O’Meara repeatedly glimpsed dusky, ephemeral streaks crossing Saturn’s B ring through the 23cm (9-inch) Clark refractor at Harvard College Observatory in Cambridge, Massachusetts. Although it would prove to be one of the last great planetary discoveries made by a visual observer, O’Meara’s description of ghostly linear features rotating like rigid bodies was initially greeted with skepticism. Kepler’s third law of planetary motion dictates that objects in the inner regions of the ring should have shorter orbital periods than those in its outer regions. Particles at the inner edge of ring B revolve around Saturn every 7.9 hours, while those at its outer edge circle the planet every 11.4 hours. Radial features that mimic a rotating lighthouse beacon or the spokes of a…

More suspense at Saturn

Mapping the geologic Moon

The Moon was always considered an astronomical object. After all, it’s located in the sky and is best observed at night. But when, in 1962, US President John F. Kennedy decided that Americans should go to the Moon by the end of the decade, it then became a geologic object. For astronauts to land on the Moon and safely return, it was necessary to know the nature and likely condition of the lunar surface. This is what geologists traditionally do — they identify the composition of the terrain as well as its origin and relation to the surrounding materials. To prepare for the Apollo landings, the task of geological mapping was put into the hands of Eugene Shoemaker, Don Wilhelms and their colleagues at the United States Geological Survey (USGS). They…

Mapping the geologic Moon

One-dimensional apodising mask

Observers use aperture masks to improve the view through a telescope, particularly under unsteady seeing. Such masks tend to fall into one of three categories. The first is off-axis, or stop-down, masks. These reduce the aperture to minimise the blurring effects of atmospheric seeing and avoid the influence of a central obstruction. These masks can produce occasional crisp, albeit lower-resolution views. The second type is focusing masks for astrophotography, such as those popularised by Pavel Bahtinov, Andrei Oleshko and others. The third kind is apodising masks, which are designed to improve the view by modifying the diffraction properties of the telescope to help resolve close double stars in the eyepiece and on camera. The most common design of the latter type is a two-dimensional, circularly symmetric apodising mask intended to modify…

One-dimensional apodising mask

Which way is up?

TELESCOPES ARE FANTASTIC tools. They are opto-mechanical eye enhancements, enabling us to see extremely distant objects with increasing clarity. And the bigger a telescope’s aperture is, the farther and fainter the objects it can reveal. Amazing! But one of the most surprising discoveries every amateur makes when they start exploring the night sky with their first telescope is that the image in the eyepiece differs noticeably from what might be expected — star patterns appear upside down or even mirrorreversed. So, what’s wrong? Don’t worry, nothing is amiss. This is how telescopes work. None of them produces a right-reading image (one that is orientated exactly as you see without the telescope). In fact, the lenses in your own eyes produce an inverted image on your retinas, and your brain does the work flipping…

Which way is up?

The RST-135 weightless mount

Rainbow Astro RST-135 US price: $3,895 (head only) rainbowastro.com What we like Small and portable Accurate Go To Works in equatorial or alt-az mode What we don't like Large periodic error Lacks periodic-error correction Hand controller steep learning curve THE ADAGE THAT ‘bigger is better’ is not aging well, at least not when it comes to astrophotography. The current trend is toward portable imaging with smaller telescopes, which means smaller mounts are needed to put them on. And along with this new emphasis on portability, a new technology has arrived — the ‘harmonic’ mount. Such units use ‘strain-wave’ gearing technology, originally developed for industrial robotics, to create compact but very strong mounts capable of handling a hefty telescope without the need for heavy counterweights to balance the load. My first encounter with strainwave gearing was at an…

The RST-135 weightless mount

Toward lunar observatories

Joseph Silk Princeton University Press, 2022 304 pages, ISBN 9780691215235 US$29.95, hardcover BACK TO THE MOON paints an exciting vision of planned human activity on and around the Moon in coming years and decades: crewed bases at craters in the south polar region and larger settlements in lava tubes; an orbiting spaceport, together with communications and data-relay satellites; robot-assisted mining of lunar resources; even tourist resorts. Importantly for author Joseph Silk (and AS&T readers), this expansive view includes giant observatories. Some distinguished scientific experts urge that further exploration of the Moon and beyond be conducted robotically, not by astronauts. But Silk, a renowned astrophysicist at Johns Hopkins University, argues that the train has left the station — whether we like it or not, humans are returning to the Moon. NASA’s Artemis program intends…

Toward lunar observatories

NEW PRODUCT SHOWCASE

New Product Showcase is a reader service featuring innovative equipment and software of interest to amateur astronomers. The descriptions are based largely on information supplied by the manufacturers or distributors. Australian Sky & Telescope assumes no responsibility for the accuracy of vendors’ statements. For further information contact the manufacturer or distributor.…

NEW PRODUCT SHOWCASE

Fold your Dob in half

ONE OF THE GREAT advantages of John Dobson’s telescope design is that it enables amateur astronomers to build big telescopes. New Zealand ATM Hamish Barker went that route some years ago with a 20cm f/6 scope that he admits was “unpopular with my wife and son when we went camping in our 1976 VW camper”. So he bought an old but excellent 25cm f/5 mirror and set out to build something a bit more compact but still quick to set up. Hamish had seen Mel Bartels’ elegant 33cm (13-inch) f/3 Zip Dob, which curls up like a fern, and that inspired him to try folding his scope as well. He quickly realised that a single fold would make the scope short enough to suit his needs, and a little sketching showed…

Fold your Dob in half

Long time coming

EXPLORING THE SOLAR SYSTEM is a long game, with travel times measured in years. And the time from when we first propose a mission to when our spacecraft sits on the launch pad, ready to leave Earth or die trying, is often much longer still. In a way, the pace is a return to that of the age of sailing ships, when explorers left home for years at a time — though we modern planetary explorers don’t physically risk our lives, just large chunks of our careers. The Voyager program, originally called the Grand Tour and first proposed in 1969, finally launched in 1977. Between 1979 and 1989, the two Voyagers visited Jupiter, Saturn, Uranus and Neptune, in brief flybys lasting just a few days each. In between were long years…

Long time coming

READERS' GALLERY

HOW TO SUBMIT YOUR IMAGES Gallery showcases the finest astronomical images that our readers submit. Send your best shots to photos@skyandtelescope.com.au. See skyandtelescope.com.au/contributions/ for guidelines.…

READERS' GALLERY

Seejubg canals on Mars

WHEN I WAS 10 years old, nothing captured my imagination more than the canals of Mars and the magnificent (and rather tragic) story Percival Lowell told of a civilisation of intelligent beings having built them to stave off extinction on their dying world. In his 1910 book Mars as the Abode of Life, Lowell described the canals as “Fine lines and little gossamer filaments only, cobwebbing the face of the Martian disk, but threads to draw one’s mind after them across the millions of miles of intervening void.” Soon after I read this, Mars came to opposition in March 1965 — the first I ever observed. With my 60mm refractor, I gazed with all my heart at the tiny, coppery pinhead of light that swam in the field of view. I…

Seejubg canals on Mars

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