What’s that musket ball doing on Mars?

Certainly catches the eye, doesn’t it? The spherical rock was photographed on September 11, 2014 by the Curiosity rover. It’s about a half-inch across and according to NASA scientists probably a concretion. Credit: NASA/JPL-Caltech/MSSS

It looks ever so much like an early 18th century musket ball, but the chances of soldiers traipsing around Mars a couple hundred years ago seems unlikely. Even if it’s the god of war. NASA’s Curiosity rover snapped this photo during a routine round of landscape imaging on September 11th.

There’s nothing like seeing a near-perfect sphere on another planet to make you sit up and wonder. First off, it’s not as big as you might think, measuring just under 1/2 (1 cm) in diameter or about the size of a marble. Second, we’ve seen spheres on Mars before – zillions of them!

Tiny “blueberries” in the Martian soil near the rock outcrop at Meridiani Planum called Stone Mountain. While other ideas have been proposed for their formation, water trickling through rocks to build concretions remains a strong possibility. Credit: NASA/JPL

The Mars Opportunity rover found countless spheres, nicknamed Martian “blueberries”, during  its exploration of Meridiani Planum. If you could hunker down for a look, they’d remind you of BBs from a  BB gun with diameters of .16 to .24 inches (4-6 mm). The spheres contain large amounts of hematite, an iron-bearing mineral, that most likely originated as concretions in layers of sedimentary rock that have since eroded away.

Groundwater moving through porous rocks can dissolve iron-containing minerals which then precipitate out as small, compact spheres. Concretions on Earth, such as Moqui balls and Kansas Pop Rocks, are considerably larger than the Martian variety, but that may be due to the different environments of the two planets. 

So our mystery sphere is probably a larger-than-usual concretion, freed from its rock stratum by wind and perhaps water erosion and now served up on a plate for Curiosity’s and eyes.

To view more pictures of the weird sphere, click HERE and scroll down toward the bottom for the Mastcam color images.

Planets, moon gather at dusk / Curiosity chews into Mt. Sharp

The crescent moon and Saturn twist the night away this evening September 27, 2014. Catch the pair low in the southwestern sky 1-2 hours after sunset. Further east, Mars joins Antares in conjunction. Stellarium

Space weather experts are forecasting a minor G1 geomagnetic storm with possible auroras across the northern U.S. and southern Canada this evening.

While you’re out watching for that telltale green arc in the north, take a few minutes to face the opposite direction. Low above the southwestern horizon you’ll find the crescent moon parked near the planet Saturn. It may be our last chance to see the planet with ease. Saturn’s been sinking into the west for some time. Tonight’s moon will guide you right to it.

A little more than a fist to the left or east of Saturn, Mars will be in conjunction with its colorful friend Antares (both are red-hued) only 3.1º to its north. Both star and planet shine at magnitude +1 though Mars is officially a hair brighter. Can you see the difference?

Photo from the Mars Hand Lens Imager (MAHLI) camera on Curiosity shows the first sample-collection hole drilled in Mount Sharp, the layered mountain that is the science destination of the rover’s extended mission. The hole is 0.63 inch wide and about 2.6 inches deep and photographed from 2 inches away. Click to enlarge. Credit: NASA/JPL-Caltech

This week NASA’s Mars Curiosity Rover drilled and gathered its first rock sample from the base of Mt. Sharp in Gale Crater. The target rock formation, called Confidence Hills, lies on the Pahrump Hills outcrop at the base of the mountain. The rock is a mudstone and softer than any of the rocks previously sampled by the rover.

Mudstone rock outcrop where Curiosity got its first taste of Mt. Sharp (drill hole at top), the rover’s main science target during its time on Mars. Curiosity landed on the planet in August 2012. Credit: NASA/ JPL-Caltech, colorized by Bob King

“This drilling target is at the lowest part of the base layer of the mountain, and from here we plan to examine the higher, younger layers exposed in the nearby hills,” said Curiosity Deputy Project Scientist Ashwin Vasavada of JPL. Scientists hope to get a look at the first rock to underlie Mount Sharp to get a picture of the environment at the time the mountain formed and what led to its formation. Mount Sharp is composed of layered sediments, some of which appear to have been deposited by water several billion years ago.

Fish-eye view taken with Curiosity’s front hazcam showing the drill at work on the Confidence Hills target at the base of Mount Sharp September 24, 2014. The rock surface is webbed with cracks. Click to enlarge. Credit: NASA/JPL-Caltech, colorized by Bob King

NASA will put the breaks on Curiosity now that it’s reached its prime science destination after traveling 5 miles (8 km) since touching down on Mars August 6, 2012. Next, the rover will deliver a powdered rock sample into a scoop on it arm, where the soil’s texture will be scrutinized to access whether it’s safe for further sieving, portioning and delivery into Curiosity’s internal laboratory instruments without clogging hardware.


MOM sends first pictures from Mars, says ‘the view is nice’

Tweet from India’s Mars Orbiter upon its safe entry into orbit around Mars September 24, 2014. Credit: ISRO

For less than it cost to make the movie “Gravity”, India built and flew a probe to Mars. AND they did it on their first attempt to reach the planet. About half of all probes sent to Mars have either crashed or gone off course. The planet’s known for its bad mojo.

India’s maiden Mars Orbiter Mission (MOM) to the Red Planet achieved orbit Wednesday, making it only the fourth country to successfully reach the Red Planet. The U.S., Europe and former Soviet Union have all sent probes to the planet beginning in the early 1960s.

MOM (Mars Orbiter Mission) now joins one European and three U.S. orbiters in a globe-encircling net of unblinking eyes on the Martian landscape and atmosphere below. You’ll recall the NASA’s MAVEN atmospheric probe only arrived last Sunday. It’s still in the checkout and orbit-shaping phase. In a few weeks, MAVEN will begin “tasting” the Martian air looking for clues of the planet’s missing water and thicker atmosphere it once possessed in abundance more than 3 billion years ago.

MOM tweeted this view of the surface of Mars today, adding “The view up here is nice.” Click to check out the probe’s light-hearted Twitter feed. Credit: ISRO

India’s total mission cost came to $74 million dollars, some $26 million less than the estimated price to film “Gravity”. MAVEN came in at $671 million, nearly 10 times as much.

Despite the Indian Space Research Organization’s frugality, critics in the home country have complained that the money could be better spent on feeding the poor and other projects. At the same time, the Indian people must feel justly proud today for this amazing accomplishment.

Indeed, that’s part of the mission’s purpose – to demonstrate that the county has developed technological prowess in the field of space exploration. All the instruments on board were built in India, including the cameras to photograph and map the surface, sensors to detect methane (an organic compound found in small quantities on Mars that may or may not be connected to potential microbes) and spectrometers to map minerals on the surface.

Photo of the planet and its dusty orange-brown atmosphere. Says MOM: ” I’m getting better at it. No pressure.” Gosh, the spacecraft even cracks jokes! Credit: ISRO

The Mars Orbiter Mission, also known informally as Mangalyaan after the Sanskrit words “Mangala” for Mars and “yana” for craft. MOM will orbit and study Mars for about six months until it runs out of fuel it needs to maintain orbit.

The folks behind the Twitter feed for MOM post updates with a light touch as you can tell from the probe’s first-person conversational style. This people-friendly approach is a great way to involve everyone in the mission. NASA does it too. Matter of fact, when MOM entered orbit, Curiosity tweeted: “Namaste! (Hindi for “greetings) Congratulations to @ISRO and India’s first interplanetary mission upon achieving Mars orbit.”

MAVEN makes it safely to Mars!

This image shows an artist concept of NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission. Credit: NASA/Goddard Space Flight Center

After 10 months and over 422 million miles (771 million km) of travel, NASA’s Mars Atmosphere Volatile EvolutioN spacecraft settled safely into orbit around Mars Sunday evening at 9:24 p.m. Central Daylight Time. Engineers and scientists waited tensely as the onboard computers fired thrusters for 33 minutes to slow the craft enough so it could be captured by Mars’ gravity. The operation went smoothly.

MAVEN joins a fleet of other craft working at the Red Planet including Mars Odyssey, Mars Express and Mars Reconnaissance Orbiter and the two rovers, Opportunity and Curiosity. On Wednesday, India’s Mars Orbiter Mission (MOM) will join the clan as it too brakes to settle into orbit.

“This was a very big day for MAVEN,” said David Mitchell, MAVEN project manager from NASA’s Goddard Space Flight Center, Greenbelt, Maryland. “We’re very excited to join the constellation of spacecraft in orbit at Mars and on the surface of the Red Planet. The commissioning phase (when the instruments will be checked and orbit slimmed from 35 to 4.5 hours) will keep the operations team busy for the next six weeks, and then we’ll begin, at last, the science phase of the mission. Congratulations to the team for a job well done today.”

Mars was once a much wetter and warmer planet (left) than it is today. Because it’s not protected by a planet-wide magnetic field like Earth, it’s thought that the sun and solar wind stripped away its atmosphere over time, leading to a cold, dry desert world (right). Credit: NASA

MAVEN’s primary mission will last one Earth year taking measurements of the composition, structure and escape of gases in Mars’ upper atmosphere and its interaction with the sun and solar wind. Without protection from a planet-wide magnetic field, it’s thought that the sun and solar wind have stripped molecules from the Martian atmosphere over time. MAVEN will dip into Mars’ atmosphere only 93 miles (150 km) above the surface to study how and what kinds of atoms are disappearing. Several deeper-dip missions will bring it to within 78 miles (125 km) altitude.

For more on MAVEN, check out the MAVEN website and this article in Universe Today.

Jupiter-moon conjunction / Space station expecting guests / Hello Mars!

Tomorrow morning September 20th the crescent moon will be lined up in conjunction with the planet Jupiter ahead of the Sickle of Leo. This view shows the sky a little more than an hour before sunrise. Stellarium

Getting a little extra sleep these September mornings? That benefit comes from later sunrises as we approach the fall equinox. I don’t know about you, but I sleep better in a darkened bedroom.

The rate of change has really picked up in the past few weeks with the sun now rising around 7 o’clock, a far cry from late June’s 5:15.

Later sunrises also mean a chance to catch an early morning sky event. Many of us are active around 6 a.m. prepping for work or getting your children ready for school. If you can find a few minutes to spare, tomorrow morning offers up two fine sights.

Look east in the brightening dawn and you’ll see a slender crescent moon in conjunction with the brightest of the planets, Jupiter. The two will just 5º apart meaning you’ll be able to squeeze three fingers held at arm’s length between them. Then, between 5:30-6:15 a.m. now through at least next week, the International Space Station (ISS) will be making regular passes across the northern sky from many locations across the U.S., Canada and Europe.

To find out exactly when and where to look, key in your zip code at Spaceweather’s Satellite Flybys site or select your city at Heavens Above. The ISS looks like the brightest “star” in the sky and travels from west to east. A typical complete pass takes about 5 minutes.

An earlier SpaceX Dragon capsule docking with the space station in March 2013. Astronauts will use the grapple arm to grab the capsule Monday morning Sept. 22 at around 6:30 a.m. CDT. Berthing begins around 8:45. Click to enlarge. Credit: NASA

The three current astronauts aboard the space station await the arrival of the other half of their crew next week. NASA astronaut Barry Wilmore, Soyuz Commander Alexander Samokutyaev and Flight Engineer Elena Serova will launch aboard their Soyuz spacecraft from the Baikonur Cosmodrome in Kazakhstan on Sept. 25 to begin a six-hour, four-orbit trek to the orbiting complex.

Before that, SpaceX’s unmanned Dragon ship will launch tomorrow morning Sept. 20 at 1:14 a.m. Central time to deliver cargo and crew supplies to the ISS early Monday morning Sept. 22nd.

Among the items are the first 3D printer in space, the ISS-RapidScat instrument to monitor ocean winds for climate research and weather forecasting and a commercial experiment designed to make a better golf club. The printer will allow astronauts to make their own tools and replacement parts that would otherwise cost a lot of money to ship up from Earth.

Fruit flies such as these spent one month aboard the International Space Station during an earlier study. More are on the way. Credit: NASA / Dominic Hart

20 female mice and 30 fruit flies will also go along for the ride. The mice will be housed in the new Rodent Research habitat, where they’ll be studied for the effects of spaceflight on the human body. In space, rodents don’t spend their time floating around. They’re very physically active but tend to hold onto the walls.

Fruit flies will be monitored for the effects of oxidative stress changes which happen in organisms ranging from fruit flies to humans. Oxidative stress involves a build up of harmful molecules inside cells that can cause cell damage, and it’s associated with infections and disease.

Artist view of India’s Mars orbiter at Mars. Arrival and orbit insertion is expected for Sept. 24. Credit: ISRO

There’s much more in the works for space mission news as Mars welcomes two new emissaries from Earth. NASA will insert the MAVEN spacecraft into orbit around Mars Sunday night, and India’s Mars Orbiter Mission (MOM) will arrive at the planet only three days later on Sept. 24.

The MAVEN mission will study Mars’ climate present and past as scientists try to figure out how the planet evolved from a warmer, wetter past to the current dry, cold desert. MOM is India’s first-ever mission to another planet. While primarily a demonstration and testing of that country’s technology, MOM will also photograph the Red Planet and study its mineral makeup from orbit.

Follow Mars to Dschubba, whirling dervish of the night

Photo taken last night in late twilight at 8:30 p.m. looking southwest. With Mars nearby, finding our featured star Delta Scorpii is a snap. The two will be closest tomorrow night September 17th. A car zoomed by during the 20-second exposure. Credit: Bob King

Looked at Mars lately? If you haven’t I’m not surprised. It’s lost it’s luster since spring and rides the “low path” in Scorpius in the southwestern sky at dusk. From my home in the mid-northern latitudes, it now spends most of its brief nightly circuit hidden behind trees. But I encourage you to look for the Red Planet over the next few evenings. It’s passing very close to a fascinating star in the head of Scorpius the scorpion, Delta Scorpii.

Delta, also known by its Arabic name, Dschubba (JOOB-a), normally shines at magnitude 2.3, a tad fainter Beta Scorpii (2.6) directly above it. But on June 26, 2000, amateur astronomer Sebastian Otero of Buenos Aires noticed something peculiar. He’d been making brightness estimates that night of stars that are constant or don’t vary in brightness.

Mars will be very near Delta in the head of Scorpius not far from similarly colored Antares tonight. The pair will be closest tomorrow night (September 17) at just a half-degree apart. Delta is an unusual variable star that’s been in outburst since 2000. Stellarium

To his surprise, when he selected Delta, he found it brighter than normal. After alerting others to confirm his result, observers around the world watched as the star slowly rose in light until peaking at magnitude 1.6 in 2003. Yes, three years later.

I got in on the fun, too, watching Dschubba outshine every star in its constellation except the brightest, Antares. The change in the appearance of the scorpion’s head was striking. It still is. While the star has fluctuated in brightness since Otero’s discovery, it remains unusually bright; current estimates place it around magnitude 1.8. And now Mars will take you right to it.

Delta Scorpii likely resembles VFTS-102 (illustrated here), the fastest rotating star found to date. It goes round at 1 million mph or 100 times faster than the sun. The incredible speed has flattened the star into an egg shape and spun off a disk of material in the star’s equatorial plane like Delta. Credit: NASA

Delta’s an amazing star despite its unremarkable appearance. Nearly 15  times more massive than the sun and located about 470 light years from Earth, it’s blazing surface shines at least 14,000 times brighter than the home star. If those aren’t superlatives enough, this star rotates at least 112 miles per second, 90 times the sun’s rate.

Studies reveal the star is disrobing right in front of our eyes, flinging mass from its equator as it spins at breakneck speed. The material accumulates in a disk around the star and is responsible for the rise in brightness and appearance of bright lines of emission in the star’s rainbow spectrum.

Dschubba has three companion stars in orbit about it. One, a cooler, fainter star with a period of 10.8 years, may be connected with the Delta’s outburst in 2000 and a second peak in brightness in 2011. Perhaps its revolution about the primary star stirs the great beast to release extra material every 11 years.

While Delta Scorpii lays low this time of year, you can still follow it into October and then watch with anticipation when it returns to the morning sky in winter. If you’d like a chart with magnitudes to estimate its brightness, click over to the AAVSO and key in Delta Sco in the “Create a finder chart” window.

Curiosity rover reaches the sublime Mt. Sharp

The next goal for NASA’s Mars Curiosity Rover – the beautiful layered rocks at the base of Mt. Sharp. Credit: NASA/JPL

You’ve seen it looming in the background of so many photo for more than two years. Finally, we’re there. NASA’s Curiosity rover rolled up to Mount Sharp in Gale Crater. With a peak 2.7 miles (4.4 km) high, Mt. Sharp stands more than a half mile higher than Mt. Ranier in Washington.

Orbital view of the 96-mile-wide Gale Crater, the peak Mt. Sharp and Curiosity’s landing site. The rover now begins its journey up the mountain’s slope. Credit: NASA

The mountain is built of layer upon layer of stratified rocks deposited by water and wind after the massive impact that excavated Gale Crater more than 3 billion years ago. From orbit, scientists have detected clays in some of the layers, an indication that water flowed here in the past.

Curiosity’s route up Mt. Sharp will first take it through the Pahrump Hills, which make up part of the Murray Formation of layered rocks. The white dashed line represents the border between rocks of Gale Crater’s plains, which Curiosity has investigated since landing, and those at the base of Mt. Sharp. Click to enlarge. Credit: NASA

As Curiosity begins its trek up the mountain’s slope, it will first trundle across the Pahrump Hills, a region of layered rocks that’s part of the Murray Formation. At some point within this broad expanse of soft rock, the rover will drill a sample and analyze it before continuing upslope. Several miles later, it will encounter a ridge of hematite-bearing rocks. Hematite is a gray version of iron oxide (rust) that precipitates in hot springs or in pools of standing water.

Orbital view of the 96-mile-wide Gale Crater showing Curiosity’s planned path up Mt. Sharp. The rover has traversed 5.5 miles to reach the mountain’s base. Credit: NASA image with illustration by T. Reyes

An intriguing layer of clay-bearing rocks that lies further upslope and offers the best opportunity of finding organic, carbon-containing minerals. A region containing sulfates, found earlier by Curiosity in the form of gypsum (calcium sulfate) extends beyond the clay layer higher yet. Gypsum is the same material used to make drywall back on Earth.

More detailed view of a potential path up Mt. Sharp from an earlier study this year showing the different terrains Curiosity will traverse. Credit: NASA/JPL

Scientists hope to study the transition between the two. Sulfates point to a time when the ancient, more watery Mars evolved from a wet, fresh-water climate to a drier one with acidic waters that favored the formation of sulfates instead of clays.

We all hope Curiosity’s wheels, poked and torn by sharp rocks, will be up for the long journey ahead.

“In late 2013, the rover team realized a region of Martian terrain littered with sharp, embedded rocks was poking holes in four of the rover’s six wheels. This damage accelerated the rate of wear and tear beyond that for which the rover team had planned. The team altered the rover’s route to a milder terrain, bringing the rover farther south, toward the base of Mount Sharp”, according to NASA.

A view of Mars taken on September 12, 2014 by the Curiosity rover’s hazard avoidance camera. Inset shows a big hole in one of the rover’s aluminum wheels from 2013. Looks rough out there! Credit: NASA/JPL

Curiosity has already fulfilled its initial goal of determining whether Mars ever offered an environment suitable for the formation and development of early life. Clay-bearing rocks in the Yellowknife Bay site revealed an ancient lakebed that once lapped with fresh water and contained the key elemental ingredients for life - sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon – as well as a sulfate energy source potential life could use to thrive.

Moon, Mars, Saturn and Antares gather at dusk tonight

The crescent moon, Saturn and Mars will form a compact triangle in the southwestern sky in this evening August 31st. 3.5º separate the moon and Saturn; Mars and Saturn will be 5º apart. Antares is about two ‘fists’ to the east or left. Stellarium

Don’t miss tonight’s sweet gathering of crescent moon and evening planets. Just look to the southwest in late twilight to spot the trio.

Both Saturn and Mars happen to be exactly the same brightness, shining equally at magnitude 0.8, but each with a distinctly different hue. Can you see the contrast between rusty red Mars and vanilla-white Saturn?

Antares is a red supergiant that’s blowing a powerful stellar wind into space at the rate of several solar masses every million years. One day it’s likely to explode as a supernova. Credit: Wikimedia

All this happens in Libra, a dim zodiac constellation preceding the brighter and better known Scorpius. Scorpius brightest star, Antares, is similar to Mars in color and just a tad fainter.

Visually, this red supergiant star doesn’t even hint of its true proportions because it’s 620 light years away, too far to appear as anything more than a shifting point of light. Measuring in at three times the diameter of Earth’s orbit, if Antares were put in place of the sun, its bubbly surface extending beyond the orbit of Mars.

How Antares would appear if we could get close enough to see it based on simulations by A. Chiavassa and team. Huge convective cells of rising and sinking gas crinkle its surface. Click to read the group’s 2010 research paper on the star. Credit: A. Chiavassa et. all

Recent research shows the star dominated by enormous bubbles of incandescent hydrogen gas called convective cells. Although it has a mass some 18 times that of the sun, the star’s powerful winds – from convection and sheer radiant energy – blast away something like 3 solar masses of material into space every million years. Unless Antares slims down through mass loss, it’s destined to grow a core of iron, collapse and explode as a supernova in the future.

Mars and Saturn boogaloo with Zubenelgenubi

Mars and Saturn are now only about 7 degrees apart (a little more than three fingers) low in the southwestern sky at dusk. This view shows the sky about 90 minutes after sunset. Between the two, you can spot the dimmer star Zubenelgenubi, the brightest star in the constellation Libra the Scales. Stellarium

Evening planets Saturn and Mars are fading and dropping lower in the western sky as August ticks toward September. Remember when Mars was brighter than Arcturus this spring? Planets. They never sit still. Their light’s never constant. We love watching them change, which is why our ancient ancestors knew immediately they were different from the static stars.

From my house, I need to be vigilant to spot Saturn and Mars before they’re lost in the treetops. That means getting out about an hour after sunset in fading twilight and finding an open spot where I can look low in the southwestern sky.

You may have noticed that the two have slowly been drawing together over the past few weeks. Mars, much closer to Earth than Saturn, moves more quickly across the sky. It’s been ‘chasing’ slower Saturn for some time now.

Mars gets closer to Saturn with each passing night until August 25 when they’ll be in conjunction just 3.4 degrees apart (twice as close as tonight). Watching Mars move against much slower Saturn makes a fun and easy observing project. Stellarium

Tonight, the two planets will be 7 degrees apart on either side of Libra the Scales’ brightest star, Zubenelgenubi (zoo-BEN-el-je-NEW-bee). The name, a delight to pronounce, is pure Arabic and means ‘southern claw’. Libra’s stars used to belong to neighboring Scorpius and both it and nearby Zubeneschamali (northern claw) remind of us of times long ago when Libra belonged to Scorpius.

Zubenelgenubi (a.k.a. Alpha Librae) is a double star that observers with keen vision can split with the naked eye. Most of us will find that a pair of binoculars will make the job much easier.

Mars will soon pass its slower brother but not before the two are in conjunction and closest together on the evening of August 25th. Watching two planets pass in the night is fun and instructive – it makes us aware that everything in our solar system’s on the move.

This weekend we’ll look at another even more amazing planetary conjunction coming up very soon – Jupiter and Venus on August 18.

Mars-bound comet scores a galactic ‘ringer’

Comet C/2013 A1 Siding Spring passes the beautiful ring galaxy NGC 1291 in the constellation Eridanus the River on August 2, 2014. Credit: Damian Peach

Comet C/2013 A1 Siding Spring  has been gaining ground on the planet Mars with only 208 million miles separating the two as of today. Discovered in January 2013, astronomers quickly determined the comet would pass only 82,000 miles from the planet on October 19 this year.  That’s more than 10 times closer than any comet has ever been observed to pass by Earth.

Because of the possibility for stray dust particles from the comet’s tail to damage instruments on several of its orbiters, NASA recently initiated orbital maneuvers to place them out of harm’s way on the opposite side of the planet during the time of closest approach.

Meanwhile, observers in the southern hemisphere have been keeping watch on the comet through modest-sized telescopes as have astrophotographers like Damian Peach who shared this remarkably beautiful photo of C/2013 A1 passing by the peculiar galaxy NGC 1291 in Eridanus. No danger of those two ever brushing up against one another –  the galaxy’s about 33 million light years in the background.

When we’re near the orbital plane of a comet, we look across space nearly edge-on into the cloud of dust it sheds. From our perspective, the tails and dust collapse into a flattened streak with the comet’s core or nucleus near the center. An anti-tail is really a dust or gas tail, but it appears to precede the comet instead of trail it, hence the term ‘anti’. Credit: Justin J. McCollum

Two things to notice here – the comet’s peculiar stretched-out shape and the galaxy’s striking interior ring.

Earth recently crossed Siding Spring’s orbital plane, providing with a unique, nearly edge-on view of the comet. Tails as well as dust shed in the its path stack up to form a flattened ‘pancake’ comet for a few brief days or weeks. (see diagram).

Composite image of NGC 1291  from the Galaxy Evolution Explorer and data from the Cerro Tololo Inter-American Observatory in Chile shows brilliant, massive stars firing up inside the ring. Galaxy rings may also form when galaxies pull in material from their surroundings. Shocked and heated through compression, new stars form. Credit: NASA

A number of galaxies show rings but few as symmetrical as NGC 1291. It’s thought that ring galaxies form when another galaxy collides and passes straight through the host galaxy.

While stars rarely crash during such encounters, merging gas clouds and gravitational disruptions can spark waves of star formation. Images taken by NASA’s Galaxy Evolution Explorer ultraviolet telescope clearly shows a ring of massive, young blue stars.

Beauty can be so happenstance.