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 know 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.

Hole-y auroras possible tonight Aug. 30-31 / Jupiter returns

The dark opening at the center of the sun’s disk, seen here in ultraviolet light, is a coronal hole photographed on August 28 by the Solar Dynamics Observatory. Holes are ports through which high speed particles from the sun can pour freely into space unconstrained by solar magnetic fields. Credit: NASA

Sometimes it doesn’t take a big solar storm to incite an aurora. Often enough, a hole will do. Midweek, a blizzard of electrons and protons called a coronal mass ejection arrived in Earth’s vicinity, snuck past our magnetic defenses and painted northern skies for several nights in a row with glowing curtains and rays.

Yesterday night, a coronal hole did the same. Coronal holes are openings in the sun’s otherwise ‘locked down’ magnetic canopy. In the photo above, swirls of magnetism form closed loops over most of the sun’s lower atmosphere, keeping the bubbling sea of solar plasma (charged particles) at bay.

Enhancements in the solar wind either from solar storms (CMEs) and coronal holes send a thin soup of electrons and protons into space. If a batch happens to have a southward-pointing magnetic field, it can open a crack in Earth’s northward-pointing field and stimulate oxgen atoms and nitrogen molecules to glow in the upper atmosphere. The aurora is concentrated in two ovals, one hovering over each magnetic pole. Credit: Todd Salat

The sun’s so hot that it energizes and accelerates bits and pieces of itself – electrons and protons – to speeds high enough to escape its gravitational pull. Astronomers call the gust of departing particles the solar wind. Typical speeds hover around 250 miles per second (400 km/sec), but winds leave coronal holes unchecked and can blast into space at up to 500 miles per second (800 km/sec).

When the tempest arrives at Earth and harbors south-pointing magnetism, it links into Earth’s north-pointing magnetic field, sending electrons and protons at high speed down the planet’s magnetic field lines into the upper atmosphere to spark auroras.

Coronal holes are holes where the sun’s magnetic field where the solar wind can escape at high speed. Credit: NASA

NOAA space weather forecasters expect the effects of coronal holes to continue tonight and linger through Monday. Peak possibility for northern lights tonight happens between 10 p.m. and 1 a.m. CDT. Sometimes a particular hole can persist for several solar rotations causing repeat auroras every 27 days.

Stay tuned to Ovation aurora to see if any auroras are dropping south toward your region tonight.  I’ll be in touch.

Jupiter (top) and Venus in bright twilight on August 27, 2014. Credit: Bob King

The other morning while watching aurora I was happy to see that Jupiter had jumped back into the sky. It cleared the trees during twilight and was followed a half hour later by Venus. Low elevation and wiggly air currents meant I couldn’t magnify it much, but at 64x but north and south equatorial belts were unmistakeable.

I always look forward to that first view of Jupiter after conjunction with the sun. We last saw the planet in June, quite a while back. Jupiter’s weather and cloud patterns constantly change. One never knows what to expect when it’s out of sight for a couple months – sometimes an entire equatorial belt can disappear! I’m hear to report that both are still intact.

Farthest planet Neptune closest to Earth tonight – how to see it

Even though it’s 2.8 billion miles from the sun, Neptune shows seasonal changes in cloud patterns over its 165-year orbit. Photos made with the Hubble Space Telescope. Credit: NASA

Only two planets didn’t jump out and bite us in the days of antiquity – Uranus and Neptune. Both escaped attention because they were too faint. Now all you need to see either is a pair of binoculars. Pop off those lens caps because we’re going to visit the solar system’s outermost planet, Neptune, now at its closest and brightest for the year.

To find Neptune, face southeast around 10-10:30 p.m. Start with the bright star Altair in the bottom of the Summer Triangle in the south. Shoot a line from Altair about two outstretched fists long to the lower left to Beta Aquarii. Continue “sliding” in that direction to Theta. From there it’s just a short hop to dimmer Sigma Aquarii. Point your binoculars or scope at Sigma and use the map below to spot Neptune. You can also use the Y-shaped asterism nicknamed the Water Jar below the Square of Pegasus to navigate to Theta. Stellarium

Neptune reaches opposition today in the constellation Aquarius, a dim assemblage of stars to the west and south of the familiar Square of Pegasus. Opposition occurs when the Earth lines up on the same side of the sun as an outer planet. Not only are the planets at their closest, but Neptune remains visible all night long, rising at sunset in the southeastern sky.

Earth, a rocky planet, has a diameter of 7,918 miles. Neptune is 30,600 miles in diameter and has a deep atmosphere with a mix of water and other ‘ices’ in its interior. At its center is a ball of rock made of iron and silicates with a mass of 1.2 Earths. Credit: NASA

‘Close’ in astronomy is always a relative term. At 2.7 billion miles from the good, green Earth, Neptune is one of the coldest places in the solar system. Where its methane-laced clouds meet against the vacuum of space the temperature drops to -360°F (-218° C). Powerful winds up to 1,250 mph (2,000 mph), stretch its chill blue clouds into subtle belts and bands that whiz through an atmosphere of mostly hydrogen and helium.

Deeper down, Neptune’s mantle resembles nothing on Earth – a superheated fluid of water, ammonia, methane referred to as ice but simmering under high pressure at temperatures between 3,000 – 8,500° F.

Hubble Space Telescope pictures showing Neptune and its system of dim ring arcs along with several of its moons. The 14th and newest is S/2004 N1, discovered last year. Credit: NASA

All these amazing facts are distilled into a minute blue-colored dot just 2.4 arc seconds in diameter (750 times smaller than a full moon) as viewed from Earth’s skies.  Being so far away, Neptune takes 165 years to make a complete circuit around the sun. Since its discovery in 1846, the blue planet has completed just one single orbit. That was back in 2011. It’s a long time between birthdays on planet #8.

Despite its great distance, Neptune’s size and bright cloud cover make it a fairly easy find. At magnitude +7.6, you can spy it in 35mm or larger binoculars from the outer suburbs and countryside.  What will you see? In binoculars, the planet looks like a dim ‘star’ that slowly creeps westward among the real stars. You can easily track its progress if you look one night, note the planet’s position, and look again a few nights later.

A detailed map showing Neptune tracking near the star Sigma Aquarii in Aquarius over the next month. The planet should be easy to pick out as there are no stars of similar brightness close by to cause confusion. The field of view is about 1.5 degrees. Source: Chris Marriott’s SkyMap software

Discerning Neptune’s tiny disk will require at least a small telescope and magnification of around 100x. The planet looks like a pencil-point dot.  I like to crank up the power to 250x on good nights to try and see its brightest, largest moon Triton, which looks for all the world like a 13th magnitude companion star.  To know where to look for the moon at any time and date, visit Sky and Telescope’s Triton Tracker.

As we transition into fall, Neptune rises higher and earlier with each passing night. Take a look now and again to watch the slow gait of a world that’s been hidden from human eyes until only recently.

5 landing sites picked for daring comet touchdown

The approximate locations of four of the five landing sites are marked on these OSIRIS narrow-angle camera images taken on August 16 from a distance of about 62 miles (100 km). Click to enlarge. Credit: ESA

Five potential sites have been selected for what will be one of humanity’s most audacious undertakings – landing a spacecraft on a comet. Scientists will command the Rosetta spacecraft to ‘drop’ the washing-machine-sized lander called Philae onto comet 67P/Churyumov-Gerasimenko’s dusty surface on or about November 14.

Craggy crater walls and boulders of all sizes highlight this photo taken of Comet 67P/C-G on August 23, 2014. Credit: ESA

If mission controllers are feeling anxious, it’s no surprise.  Philae must land on the 2.5-mile-wide dirty iceball before heat from the sun makes it hazardous. Compared to a rocky asteroid, a comet’s practically alive with activity. The closer it gets to the sun, the faster its ices vaporize and the more dust the comet releases.

The last thing scientists want is to send the lander into a blizzard of dust and water ice crystals which could pose clear hazards to Philae and its suite of 10 instruments.

During the maneuver,  Rosetta and 67P/C-G will be 280 million miles (450 million km) from the sun, far enough (and cold enough) that the rate of vaporization and ‘geysering’ of water vapor from cracks in the comet’s surface will be low.

Model of a typical coma like 67P/C-G. Dust-laden ice boiled from the comet’s nucleus by the sun forms a head or coma and typically two tails, one of dust, which lags somewhat behind the comet, and one of fluorescing gases called the gas or ion tail which points directly opposite the sun. Credit: ESO / E. Slawik

An early landing also means scientists get a first-hand look at the surface ices and chemistry before solar heating changes the landscape, converting dirty ice into the vapor and dust that will expand the comet’s coma and flow into a tail. Scientists would like to sample and observe these goodies in as pristine a state as possible.

Comets, which have remained frozen in the far corners of the solar system since shortly after their formation, bear news from a distant and ancient era. Studying one in situ is like following a proverbial trail of breadcrumbs back to its beginning.

The five landing sites A, B, C, I and J. Credit: ESA

“The process of selecting a landing site is extremely complex and dynamic; as we get closer to the comet, we will see more and more details, which will influence the final decision on where and when we can land,” said Fred Jansen, Rosetta’s mission manager from the European Space Agency’s Science and Technology Center.

Rosetta’s lander will obtain the first images taken from a comet’s surface and will provide comprehensive analysis of the comet’s possible primordial composition by drilling into the surface. The tool can penetrate up to 10 inches deep.

Five candidate sites were identified on Comet 67P/Churyumov-Gerasimenko during the Landing Site Selection Group meeting held August 23-24, 2014. Credit: ESA

From an original 10 sites, lettered ‘A’ through ‘J’, the search has been narrowed to five. Three sites (B, I and J) are located on the smaller of the two lobes of the comet and two sites (A and C) are located on the larger lobe. Choosing the right one is a complex process based on several considerations:

* We need a location with at least six hours of daylight during the comet’s 12.4 hour rotation, both for good illumination of the surface for detailed photography and to provide power to Philae’s batteries via solar cells. But not too much sunlight, otherwise the probe could overheat.

* Flat terrain with as few boulders, cliffs and crevasses as possible for safety’s sake. While the boulders in the photos cry out for exploration, they’re too hazardous to approach. Mission controllers prefer safe and (somewhat) boring. Better than than losing the craft.

* An area where the lander can maintain regular communications with the Rosetta mother ship during its descent to the surface and after landing.

Artist’s view of the lander Philae touching down on the dusty-icy surface of comet 67P/C-G. Credit: ESA

“The five chosen sites offer us the best chance to land and study the composition, internal structure and activity of the comet with the ten lander experiments,” said Jean-Pierre Bibring, one of the lead lander scientists.

Uncertainties in navigating the orbiter close to the comet mean that it’s only possible to specify any given landing zone in terms of an ellipse about four-tenths of a square mile (one square km). By September 14, the sites will be accessed and ranked and the best will be selected along with a backup.

For more on site selection, including profiles of each of the five, click HERE.

 

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Quiet aurora tonight Aug. 27-28

A lquiet auroral arc topped by a faint pink band glowed softly in the northern sky tonight at 10:30 p.m.. The bright star at right is Capella in the constellation Auriga. Credit: Bob King

After Wednesday morning’s fine display, the current wave of magnetic activity is subsiding but not without leaving a tasty leftover. A low, quiet arc has hovered over the northern horizon all evening. Maybe it will take off again as the aurora did this morning, but the forecast indicates a gradual decline in activity overnight.

Map showing the extent of the auroral oval early this Thursday morning August 28. The arc in the photo above is the edge of the large, permanent oval of aurora centered on Earth’s geomagnetic pole. In this map, which is based on satellite data, you can see that the edge of the oval lies right at Minnesota’s northern border. Click to see the current oval. Credit: NOAA

If you live in in the northern U.S. away from city lights and enjoy the subtle side of nature, you’ll find tonight’s aurora suitable for contemplation.

Beautiful rays of aurora dapple the dawn sky

At 4:45 a.m. CDT this morning (Aug. 27) spectacular rays erupted from a low, bright green arc and paraded across the northern sky. Credit: Bob King

Maybe it’s because of the name aurora, which means ‘dawn’, but that’s exactly when the northern lights put on one great show this morning. With clouds constantly a bother this late summer, many of us have been thwarted in viewing all manner of conjunctions, comets and moonrises. Not this morning. I was determined to see Comet Oukaimeden near Orion just before dawn. And that’s exactly how I happened to be up to catch a surprisingly fine aurora.

A striking green arc perforated by many needle-like rays. Credit: Bob King

One of the keys to maximizing enjoyment of the aurora is to have a place you can get to with a low northern horizon. At least from mid-northern latitudes, lots of activity often occurs very low in the northern sky.

High speed electrons from the sun spiral down individual magnetic field lines in Earth’s magnetic bubble called the magnetosphere to create multiple parallel rays when they strike oxygen and nitrogen atoms in the upper atmosphere. Credit: Bob King

We were already primed for northern lights because of the NOAA space weather forecast, so when I looked out the window at 4 a.m., there they were.

I jumped in the car and sped to a country road not far from home. Arriving around 4:30 a.m. several pale green arcs snaked across the north, and within minutes they erupted with massive parallel rays. To the eye, the tall rays were colorless, but they loved the time exposure afforded them by the camera.

The pictures were taken using a 17mm lens at f/2.8, ISO 800 and exposure times around 15 seconds.

While I did get to see my comet in the nick of time, the northern lights made it more than worth my while. I hope you got to see them, too.

Jupiter (lower left next to the star Delta in Cancer) and Orion (upper right) sparkle in the dawn sky over Duluth, Minn. Wednesday morning. Credit: Bob King

The display continued deep into twilight and no doubt carried into darker skies farther west of my location. There’s still a possibility for minor auroras early tonight. I hope so. Two 4 a.m. stints in a row would kill me.

Aurora alert tonight Aug. 26-27 – updated

Painting by Etienne Trouvelot of a spectacular aurora observed on March 1, 1872.

North Americans skywatchers missed the last week’s aurora by the skin of our teeth. By nightfall, the whole display, enjoyed earlier from Scandinavia, went to heck. Maybe tonight will be different.

For the past few days NOAA space weather forecasters have been predicting a minor geomagnetic storm (Kp = 5) from incoming blasts of solar particles called coronal mass ejections that departed the sun on Aug. 22. ‘Minor’ often translates to an auroral arc (sometimes two) low in the northern sky pierced by occasional rays.

No great shakes, but if you live in the northern U.S. and southern Canada, be aware you might be visited by the green ghost. Activity should commence after sunset and peak between 1-4 a.m. CDT tomorrow morning Aug. 27.

Maybe we’ll get burned again. But you wouldn’t want me to keep this all to myself, would you?

* UPDATE 5:30 a.m. CDT: Big auroras lit up the northern sky this morning. Lots of arcs and long rays seen from Duluth, Minn. If you live in the northern third of the U.S. and it’s still dark, go out for a look.

What do stars sound like? Listen in


Singing stars – how astronomers turn starlight into sound

Fluttering, sizzling hiss, alien music. These are the sounds the stars make.

Animation showing an extrasolar planet passing in front of a star, causing its light to dim. By studying the light curve astronomers can determine planets sizes and other details. Credit: Transits of Extrasolar Planets Network

NASA’s Kepler space telescope observed 150,000 stars looking for telltale dips in their light that would indicate a planet cycling in front of a star. Knowing the distance and diameter of the star and the length of time the passing object dimmed the star’s light, astronomers can determine the planet’s size and mass.

Using the ‘transit method’, scientists have mined Kepler data to uncover 4,229 candidate extra-solar planets 981 of which are confirmed. Finding planets, which are typically much smaller than their host stars, is no easy business. Any noise in the data can hide the weak change in light caused by an orbiting object. But sometimes the noise itself can yield useful new information.

Solar granules, each about 900 miles across (1,500 km), bubble up from below, cool and sink back down. A typical granule lasts 8-20 minutes.

Star brightness is not constant, especially if you look closely over short intervals of time. Starspots (stellar versions of sunspots), flares and even the bubbles of heated gas called rising from the star’s hotter interior to the surface cause subtle changes in its brightness.

The last is called granulation and gives the sun’s surface a grainy or cellular texture. Plumes of rising gas are hot and bright but soon darken, cool and sink back down only to be re-heated and rise again. Seen in sped-up time, they cause a star to flicker.

In a recent paper that appeared in Nature, Fabien Bastienne of Vanderbilt University in Nashville and team analyzed the noise from the Kepler data and discovered that brightness changes under 8 hours directly relate to a sun-like star’s surface gravity. Smaller stars with higher surface gravity have less granulation than big ones with less gravity.


Turning sound into light and back again. How it’s done

Now here’s the beautiful thing. You can take these slight but continuous changes in a star’s brightness and convert them into sound. The accompanying video shows how an audio signal from a pocket radio, for instance, can be turned into light and then transformed back into sound using little more than an LED and solar cell.

With Kepler, the brightness variations were sped up and converted into sound, giving stars a ‘voice’. Starspots create the fluttery sounds, granulation the hiss. Small stars flutter a lot; red giants are big hissers.

Being a dwarf star in the grand scheme of things, the sun flutters much like the dwarf star in the video. To my ear, it sounds ominous, like background music for a dystopian sci-fi flick. Rotation speed also causes variations in sound.

Scientists use these curious hisses and flutters to help nail down a star’s size, mass and stage of its evolution. The more precisely we know those details, the more precisely we also know a transiting planet’s size and mass.

Motto of the story: Don’t throw away your garbage. There’s valuable data in there!

Sharing stars and making comets at Northwoods Starfest

7-year-old Madeline Chopp of Green Bay, Wis. laughs as she peeks into her dad Brian’s scope Friday evening. Credit: Bob King

Every August, the Chippewa Valley Astronomical Society (CVAS) holds a two-night star party at Hobbs Observatory near Fall Creek, Wisconsin. Tucked in a patch of forest between cornfields, Hobbs’ dark skies entice amateur astronomers across the Midwest to get their fill of nebulae, galaxies and comets otherwise lost in the glow of city lights.

Guest speakers, good food and great conversation liven up the mix and always make for an immensely satisfying weekend. Whenever you spend time with those who share your passion, you can’t help but come away energized.

Mike Brown, CVAS president, assembles his self-built, computer controlled 24-inch Dobsonian reflector Friday afternoon. He uses an iPad and tracking software to slew quickly to any object in the sky with a tap on the keypad. The club’s radio dish is seen in the background. Credit: Bob King

I attended Friday and set up my 15-inch (37-cm) reflector on the sandy flats among dozens of other telescopes. All types were represented – small to medium refractors, binoculars on homemade mounts and reflecting telescopes with mirrors up to 24-inches (61-cm) across. The club even operates a radio telescope.

Friday night I spoke on comets and the European Space Agency’s Rosetta Mission. Judging from the audience reaction, the ESA needs to fire up that high-resolution OSIRIS camera and shoot a lot more close-up, 3-D views of comet 67P C-G. Everyone loved the in-your-face realism of seeing the comet’s alien landscape in three dimensions.

Comet Hobbs is born during a comet-making demonstration at Northwoods Starfest Friday night. Notice the little ‘geysers’ of outgassing. Credit: Greg Furtman

After the talk, we gathered round a table to make a much smaller version of Rosetta’s comet in a bucket. I added water (comets are mostly water), molasses (sugar as organic molecules), dirt (dust embedded in cometary ices), ammonia, alcohol (methanol has been found in comets) and powdered charcoal (more carbon and to create a realistic black-coated ice ball) in a plastic bag and mixed it all together with a wooden spoon.

A real comet! 30-second time exposure of Comet Jacques at ISO 6400 with a 400 mm f/5.6 lens. Credit: Bob King

Then it was time for the crucial ingredient: dry ice. Three gloved handfuls of smoky white pellets went into the cosmic ‘stone soup’, the bag was closed and the mix crushed together into a well-packed snowball. Peeling back the plastic, a delightful mini-comet emerged replete with jets of vaporizing gas geysering from small cracks in the carbon-coated surface.

All new comets have names and this would be no exception, so we settled on Comet Hobbs, or more formally, C/2014 Q1 Hobbs. Sadly, this comet exists no more. A final observation revealed the fist-sized object had morphed into a petite puddle.

Mike Brown’s 24-inch reflector had a steady stream of customers at Northwoods Starfest this weekend. Mike treated folks to views of the globular cluster M13, Comet Jacques, the planetary nebula NGC 6210 and many others. Credit: Bob King

The night began overcast but soon turned partly cloudy. We had fun observing a real comet – C/2014 E2 Jacques – as it inched its way across Cassiopeia. The bright coma was very easy to see in 50mm binoculars. Mike Brown, CVAS president, generously shared time with anyone who wanted to see anything in his 24-inch reflector. In a big scope like that, even tiny objects like the planetary nebula NGC 6210 in Hercules invite many minutes of exploration.

Jon Dannehy of Arcadia, Wis. and Eric Norland of Duluth, Minn. have fun while standing around Eric’s homemade telescope Friday. Credit: Bob King

Another CVAS member, Greg Furtman, treated us to wide-field views of the comet and Veil Nebula in Cygnus with his homemade short-focus 6-inch (15-cm) reflector. At midnight, we welcomed the opportunity to rest our legs and recharge with the traditional ‘midnight snack’ in the campground’s dining cabin. Besides fruits, juices and chips, someone broke out a box of ice cream sandwiches. Deluxe!

Although I had to leave Saturday for work, Day 2 featured additional speakers, a swap meet, a dinner BBQ and l’m sure lots more great laughs and discussion. Nothing like hanging out with a bunch of crazy astronomers.

Comet Jacques zips through Cassiopeia – catch it this week!

Wow! Comet Jacques cuts between the Heart (right) and Soul Nebulae in Cassiopeia on August 19th. These clouds of fluorescing hydrogen gas are also known as IC 1845 and IC 1848. Click to enlarge. Credit: Michael Jaeger

Not many clear nights in my town lately – we had exactly one this week. I’m grateful because we finally got a peek at Comet Jacques, which recently climbed out of the morning sky into the familiar ‘W’ of Cassiopeia. That’s good news because it means you can spot Jacques now at nightfall instead of dawn.

Comet C/2014 E2 Jacques cruises through the W of Cassiopeia the next few nights. The view shows the sky facing northeast at nightfall in late August around 9:30 p.m. Click for a detailed map showing the comet’s position nightly through early September. Stellarium

Through a pair of 8x40s two nights ago, the comet was a faint, fuzzy patch next to the lower left star of the ‘W’. Jacques is currently making its closest approach to Earth; on August 28 it will pass us at 52.4 million miles (84 million km). While that’s a fair distance, its relative proximity causes it to move relatively quickly across the sky. Currently the comet’s puffing along at a couple degrees a day. Those with telescopes can easily see it shift position against the background stars within an hour.

Small telescopes will reveal Jacques’ largish diffuse coma and bright core. The core is where the icy nucleus hides behind a shroud of dust and gas vaporized by the heat of the sun. No one knows its exact size – thanks to all that dust – but it’s probably a mile or two across, typical of many comets.

36 pictures of Comet Jacques taken on August 17th combined into a movie show its motion and changes in its gas tail caused by interaction with the solar wind, a stream of subatomic particles blowing from the sun. Click to enlarge. Credit: Gianluca Masi

Larger scopes 8-inches and up will show varying amounts of the comet’s long, faint ion or gas tail that points to the southwest and a hint of green color in the coma from fluorescing gases.

Even though Jacques has been traveling away from the sun since closest approach on July 2, its brightness will remain nearly constant at magnitude +7 through early September because it’s ‘in the neighborhood’.

Try to spot it the next clear night. From a dark sky, the comet’s easy in binoculars and any telescope will show it. Moonlight won’t get in the way until early next month.