"The red Moon did not disappoint tonight," writes Arnar Kristjansson. Credit: Arnar Kristjansson
Like some of you, I outran the clouds just in time to catch last night’s total lunar eclipse. What a beautiful event! Here are some gorgeous pictures from our readers and Universe Today staff — souvenirs if you will — of the last total lunar eclipse anywhere until January 31, 2018. The sky got so dark, and the Moon hung like a plum in Earth’s shadow for what seemed a very long time. Did you estimate the Moon’s brightness on the Danjon Scale? My brother and I both came up with L=2 from two widely-separated locations; William Wiethoff in Hayward, Wisconsin rated it L=1. All three estimates would indicate a relatively dark eclipse.
Nicely-done sequence of eclipse phases taken early September 28, 2015. Click to enlarge. Credit: Own Llewellyn
The darkness of the umbra was particularly noticeable in the west quarter of the Moon in the giant volcanic plain known as Oceanus Procellarum. This makes sense as that portion of the Moon was located closest to the center of the Earth’s dark, inner umbra. The plain is also dark compared to the brighter lunar highlights, which being more reflective, formed a sort of pale ring around the northern rim of the lunar disk.
Salute to the final eclipse of the current tetrad that began 17 months ago. Credit: Jason Major
The bottom or southern rim of the Moon, located farthest from the center of the umbra, appeared a lighter yellow-orange throughout totality.
Wide angle view of the Moon (lower left) during totality in a star-rich sky with the Aquila Milky Way visible at right. Credit: Bob King
This is just a small sampling of the excellent images arriving from our readers. More are flowing in on Universe Today’s Flickr site. Thank you everyone for your submissions!
A crowd gather to watch the Moon during partial eclipse prior to totality. Credit: Robert SparksA hint of the penumbra shows in this photo. Hint: look near left top. Credit: Roger HutchinsonA bloody Moon iindeed! Notice how dark Oceanus Procellarum (top) appears. Credit: Chris Lyons“Super Blood Moon”. Credit: Alok SinghalNice montage of images from eclipse start to finish. Credit: Mike GreenhamOne of the most awesome aspects of the eclipse was how many stars could be seen near the Moon. This picture was taken with a 100mm telesphoto lens. Credit: Bob KingRare shot of the totally eclipsed Moon and bright meteor. Credit: VegaStar Carpentier PhotographyA lucky break in the clouds made this photographer happy. Credit: Moe AliMary Spicer made exposures of the eclipsed Moon every 5 minutes. During totality, the Moon dropped behind a tree so she had to relocate the camera, hence the small gap in the sequence. 35 shots in total and stacked into one frame using StarStax. Credit: Mary SpicerThe Moon caught after totality between clouds through a small refracting telescope. Credit: Bob KingAnother fine montage displaying all the partial phase plus early, mid and late totality. Credit: Andre van der Hoeven
Weather looking a bit iffy tonight? Using the resources described below, you just might be able to escape the clouds. Credit: Bob King
We’ve arrived at eclipse day, so now the big question is, will it be clear? My favorite forecast for major astronomical events reads something like this: Fair skies tonight with light winds and lows in the middle 50s.While I hope that’s exactly what’s predicted for your town, in my corner of the world we’re expecting “increasing clouds with a chance for thunderstorms”.
That’s just not nice. Same by you? Here’s how to find that clear spot if you’re facing bad weather tonight.
One of my favorite cloud-checking sites is the GOES East view of the U.S., Canada and Central America taken from geostationary orbit. This map shows the scene at 10:45 a.m. CDT this morning. Credit: NASA
I usually check the GOES (Geostationary Operational Environmental Satellite) images that weather forecasters use to display and animate the movement of clouds and weather fronts during the nightly newscasts. Once I know the location and general drift of the clouds, I get in a car and drive to where it’s likely to either remain or become clear. Depending on the “magnitude” of the event I might drive 50 to 150 miles. If nothing else, doing astronomy guarantees many adventures.
GOES West view of the western U.S., Canada and Hawaii taken at 11 a.m. CDT. Credit: NASA
You’ll find these most helpful images at either the GOES East site, which features a photo of the entire mainland U.S., Central America and much of Canada, updated every 15 minutes. Since the satellite taking the photos is centered over the 75° west parallel of longitude, its focus is primarily the eastern two-thirds of the U.S. and Canada. For the western U.S., western Canada and Hawaii, head over to the GOES West site.
After you set the width and height to maximum values, you’ll get a picture like this, taken at 11 a.m. CDT. Credit: NASA
Once there, you’ll be presented with a big picture view of the U.S., etc., but you can click anywhere on the map for a zoomed-in look at a particular region. Before you do, set the “width” and “height” boxes to their maximum values of 1400 (width) and 1000 (height). That way you’ll get a full-screen, nifty, 1-kilometer image when you go in close. All images have a time stamp in the upper left corner given in Universal or Greenwich Mean Time (GMT). Subtract 4 hours to convert to Easter Daylight; 5 for CDT; 6 for MDT and 7 for PDT.
You can check back all day long for fresh photos and watch the march of the clouds over time. Or you can have the site assemble up to 30 of the most recent images into an animation loop and watch it as a movie. Combing current photos, the animation and your local forecast will inform your plans about whether to remain at home to watch the eclipse or get the heck out of town.
Infrared image of the east-central U.S. at 11 a.m. CDT today. Clouds can be seen and tracked at night using the infrared channel on the GOES East and West sites. Credit: NASA
When night arrives, you can still get a reasonably good idea of where the clouds are and aren’t by clicking on the infrared channel link at the top of the site. I also like to use the NCAR (National Center for Atmospheric Research Real-Time Weather Data) site. They offer a black and white infrared option that provides a clearer picture. At the site, select your “channel” then click on one of the regional acronyms on the interactive U.S. map.
So far, we’ve been talking about the weather in real time. When it comes to forecasts, one of the most useful tools of all and a true godsend to amateur astronomers is Attilla Danko’s ClearDarkSky site. Click on the Clear Sky Charts linkto access interactive charts for thousands of locations across the U.S., Canada and parts of Mexico. For example, if you click on Illinois, you’ll get a list of sky conditions for 105 locations throughout the state. The Chicagolink pops up six rows of data-packed squares with colors ranging from deep blue to white.
The cloud cover forecast for Chicago today Sept. 27 through early Tuesday Sept. 29 as depicted in Attilla Danko’s Clear Dark Sky site. The forecasts can be sponsored for a donation by various groups or individuals. This one is by the Chicago Astronomical Society. Copyright: Attilla Danko
The first row indicates cloud clover with varying shades of blue representing the percentage of clear sky. Medium blue means partly cloudy; white indicates 100% overcast. Additional data sets include sky transparency, seeing conditions, hours of darkness, wind, temperature and humidity. While no forecast is 100% accurate, the reliability of the models Danko uses makes Clear Sky Charts one of best tools available for skywatchers. Want a real treat? If you click on one of the squares in the Cloud Cover row, a large image showing cloud cover at the time will pop up. You’ll also find another, more general interactive cloud forecast graphic at WeatherForYou.com.
Thanks to a helpful reader suggestion, I recently learned of Clear Outside, a forecasting site similar to Clear Sky Charts but worldwide. Be sure to check it out. Satellite imagery like the U.S. GOES East and West is available for European and African observers at Sat24.
So what does the U.S. look like for weather tonight? Mostly clear skies are expected from New York State up through Maine, across the center of the country, the desert Southwest and the Northwest. Expect partly cloudy conditions (with some mostly cloudy spots) for the Upper and central Midwest, and mostly cloudy to overcast skies in the southern and southeastern seaboard states.
But who knows? By using these sites, you might just improve your chances of seeing what promises to be a spectacular lunar eclipse tonight. Some of you reading this undoubtedly have your own favorite weather hangouts. Please share them with us in the comments section. The more the merrier!
As always, if you’re completely shut out, here are a few sites where you can watch it live on the Web:
Depending on how clear the atmosphere is, the Moon's color can vary dramatically from one eclipse to another. The numbers, called the Danjon Scale, will help you estimate the color of Sunday night's eclipse. Credit: Bob King
There are many ways to enjoy tomorrow night’s total lunar eclipse. First and foremost is to sit back and take in the slow splendor of the Moon entering and exiting Earth’s colorful shadow. You can also make pictures, observe it in a telescope or participate in a fun science project by eyeballing the Moon’s brightness and color. French astronomer Andre Danjon came up with a five-point scale back in the 1920s to characterize the appearance of the Moon during totality. The Danjon Scale couldn’t be simpler with just five “L values” from 0 to 4:
L=0: Very dark eclipse. Moon almost invisible, especially at mid-totality.
L=1: Dark Eclipse, gray or brownish in coloration. Details distinguishable only with difficulty.
L=2: Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright.
L=3: Brick-red eclipse. Umbral shadow usually has a bright or yellow rim.
L=4: Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim.
The Danjon Scale is used to estimate the color of the totally eclipsed moon. By making your own estimate, you can contribute to atmospheric and climate change science. Credit: Alexandre Amorim
The last few lunar eclipses have been bright with L values of 2 and 3. We won’t know how bright totality will be during the September 27-28 eclipse until we get there, but chances are it will be on the bright side. That’s where you come in. Brazilian amateur astronomers Alexandre Amorim and Helio Carvalho have worked together to create a downloadable Danjonmeterto make your own estimate. Just click the link with your cellphone or other device and it will instantly pop up on your screen.
On the night of the eclipse, hold the phone right up next to the moon during mid-eclipse and estimate its “L” value with your naked eye. Send that number and time of observation to Dr. Richard Keen at [email protected]. For the sake of consistency with Danjon estimates made before mobile phones took over the planet, also compare the moon’s color with the written descriptions above before sending your final estimate.
Graph showing the change in heating of the ground in fractions of degrees (vertical axis) as affected by volcanic eruptions and greenhouse warming since 1979. The blue shows volcanic cooling, the red shows greenhouse warming. Notice the rising trend in warming after 1996. Credit: Dr. Richard Keen
Keen, an emeritus professor at the University of Colorado-Boulder Department of Atmospheric and Oceanic Sciences, has long studied how volcanic eruptions affect both the color of the eclipsed moon and the rate of global warming. Every eclipse presents another opportunity to gauge the current state of the atmosphere and in particular the dustiness of the stratosphere, the layer of air immediately above the ground-hugging troposphere. Much of the sunlight bent into Earth’s shadow cone (umbra) gets filtered through the stratosphere.
Volcanoes like Mt. Pinatubo, which erupted in June 1991 in the Philippines, inject tremendous quantities of ash and sulfur compounds high into the atmosphere, where they can temporarily block sunlight and cause a global drop in temperature. Credit: USGS
Volcanoes pump sulfur compounds and ash high into the atmosphere and sully the otherwise clean stratosphere with volcanic aerosols. These absorb both light and solar energy, a major reason why eclipses occurring after a major volcanic eruption can be exceptionally dark with L values of “0” and “1”.
The moon was so dark during the December 1982 eclipse that Dr. Keen required a 3-minute-long exposure at ISO 160 to capture it. Credit: Richard Keen
One of the darkest in recent times occurred on December 30, 1982 after the spectacular spring eruption of Mexico’s El Chichon that hurled some 7 to 10 million tons of ash into the atmosphere. Sulfurous soot circulated the globe for weeks, absorbing sunlight and warming the stratosphere by 7°F (4°C).
Lithograph from the German astronomy magazine Sirius compares the dark, featureless lunar disk during the 1884 eclipse a year after the eruption of Krakatoa (left) with a bright eclipse four years later, after the volcanic aerosols had settled out of the stratosphere (right).
Meanwhile, less sunlight reaching the Earth’s surface caused the northern hemisphere to cool by 0.4-0.6°C. The moon grew so ashen-black during totality that if you didn’t know where to look, you’d miss it.
Two photos of Earth’s limb or horizon from orbit at sunset before and after the Mt. Pinatubo eruption. The top view shows a relatively clear atmosphere, taken August 30,1984. The bottom photo was taken August 8, 1991, less than two months after the eruption. Two dark layers of aerosols between 12 and 15 miles high make distinct boundaries in the atmosphere. Credit: NASA
Keen’s research focuses on how the clean, relatively dust-free stratosphere of recent years may be related to a rise in the rate of global warming compared to volcano-induced declines prior to 1996. Your simple observation will provide one more data point toward a better understanding of atmospheric processes and how they relate to climate change.
This map shows the Moon during mid-eclipse at 9:48 p.m. CDT. Selected stars are labeled with their magnitudes. Examine the Moon backwards through binoculars and find a star it most closely matches to determine its magnitude. If for instance, the Moon looks about halfway in brightness between Hamal and Deneb, then it’s magnitude 1.6. Click to enlarge. Source: Stellarium
If you’d like to do a little more science during the eclipse, Keen suggests examining the moon’s color just after the beginning and before the end of totality to determine an ‘L’ value for the outer umbra. You can also determine the moon’s overall brightness or magnitude at mid-eclipse by comparing it to stars of known magnitude. The best way to do that is to reduce the moon down to approximately star-size by looking at it through the wrong end of a pair of 7-10x binoculars and compare it to the unreduced naked eye stars. Use this link for details on how it’s done along with the map I’ve created that has key stars and their magnitudes.
The table below includes eclipse events for four different time zones with emphasis on mid-eclipse, the time to make your observation. Good luck on Sunday’s science project and thanks for your participation!
Mars and Regulus are already close. This photo was taken this morning (Sept. 21) about an hour 10 minutes before sunrise. Credit: Bob King
I was up before dawn today hoping to find the returning comet 205P/Giacobini and a faint new supernova in the galaxy IC 1776 in Pisces. I was fortunate to see them both. But the morning held a pleasant surprise I hadn’t anticipated. Venus rose brilliantly in the east followed by the much dimmer planet Mars some 10° to its lower left. And there, not more than a couple degrees below Mars, shone Leo’s brightest star, Regulus. At first glance both appeared about equally bright, but looking closer, it was clear that Regulus, at magnitude +1.3, bested Mars by nearly half a magnitude. What was especially appealing was the color contrast between the two with Mars’ dusty, rusty surface so different from the pure white radiance of Regulus.
On Friday morning September 25, Mars and Regulus will be just 0.8 degrees apart in the eastern sky below brilliant Venus at dawn. They’ll be nearly as close Thursday morning. Source: Stellarium
While star and planet are both close enough to catch the eye, they’re headed for an excellent conjunction Thursday and Friday mornings, September 24 and 25. The actual time of closest approach, when star and planet will be separated by just 0.8°, occurs around 11 p.m. CDT — before Mars rises for skywatchers in the Americas and Canada, but about perfect for European and African observers.
Just the same, everyone around the planet will see them less than a degree apart low in the eastern sky about 90 minutes to an hour before sunrise on those dates. Joining the scene will be Venus, now spectacularly bright against the deep blue, early dawn, and Jupiter, bringing up the rear further lower down in Leo’s tail.
Regulus is a main sequence star like the Sun but hotter. It spins so fast that it’s stretched into an oblate spheroid 4.3 times the diameter of the Sun.
Regulus, Latin for “little king”, may have received that name because it’s the brightest star in the Leo the Lion, king of the beasts. The ancient Greeks knew it by the same name, Basiliscos, as did the Babylonians before them who called it Lugal (king). Regulus is the only 1st magnitude star to sit almost directly on the ecliptic, the path followed by the Moon, Sun and planets through the sky. That means it gets regular visitors. Mars this week; Venus and the crescent Moon both on October 8. Few bright stars are as welcoming of unannounced guests.
I encourage beginning and advanced astrophotographers alike to capture the Regulus-Mars conjunction using a tripod-mounted camera. Just find an attractive setting and make a series of exposures at ISO 800 with a standard 35mm lens. Click here to find out when the Sun rises, so you’ll know what time to back up from to see the event. Now that fall brings much later sunrises, it’s not so hard anymore to catch dawn sky offerings.
It’s also a delight to see the Red Planet again, which will come to a close opposition in the constellation Scorpius next May. Let the fun begin!
Pluto’s Majestic Mountains, Frozen Plains and Foggy Hazes: Just 15 minutes after its closest approach to Pluto on July 14, 2015, NASA’s New Horizons spacecraft looked back toward the sun and captured this near-sunset view of the rugged, icy mountains and flat ice plains extending to Pluto’s horizon. The smooth expanse of the informally named icy plain Sputnik Planum (right) is flanked to the west (left) by rugged mountains up to 11,000 feet (3,500 meters) high, including the informally named Norgay Montes in the foreground and Hillary Montes on the skyline. To the right, east of Sputnik, rougher terrain is cut by apparent glaciers. The backlighting highlights over a dozen layers of haze in Pluto’s tenuous but distended atmosphere. The image was taken from a distance of 11,000 miles (18,000 kilometers) to Pluto; the scene is 780 miles (1,250 kilometers) wide.
Credits: NASA/JHUAPL/SwRI
As the hazy, lazy days of summer come to a close, the New Horizons team released a brand new set of incredible images of a very atmospheric Pluto.
Can you believe the detail in these photos? Back-lit by the Sun, we see icy plains, rugged mountains, glacier-cut terrain and multiple layers of haze just like those on a steamy August afternoon.
Just look at those pyramidal mountain peaks right next to those relatively smooth, icy plains. The backlighting highlights more than a dozen layers of haze in Pluto’s tenuous but distended atmosphere. The image was taken from a distance of 11,000 miles (18,000 km) to Pluto; the scene is 230 miles (380 km) across. Credits: NASA/JHUAPL/SwRI)
The scene measures 780 miles (1,250 kilometers) across and was taken from a distance of 11,000 miles (18,000 km) on July 15 just after closest approach. Because backlighting highlights fine aerosols suspended in the atmosphere (think of seeing your breath on a cold winter day against the Sun), these photos show the amazing complexity of Pluto’s atmosphere with more than a dozen thin haze layers extending from near the ground to at least 60 miles (100 km) above the surface.
In this small section of the larger crescent image of Pluto, the setting sun illuminates a bank of fog or low-lying near-surface haze sliced by the parallel shadows of many local hills and small mountains. The image was taken from a distance of 11,000 miles (18,000 km), and the width of the image is 115 miles (185 km). Credits: NASA/JHUAPL/SwRI
“This image really makes you feel you are there, at Pluto, surveying the landscape for yourself,” said New Horizons Principal Investigator Alan Stern in a press release today. “But this image is also a scientific bonanza, revealing new details about Pluto’s atmosphere, mountains, glaciers and plains.”
Sputnik Planum is the informal name of the smooth, light-bulb shaped region on the left of this composite of several New Horizons images of Pluto. The brilliantly white upland region to the right may be coated by nitrogen ice that has been transported through the atmosphere from the surface of Sputnik Planum, and deposited on these uplands. The box shows the location of the glacier detail images below. Credits: NASA/JHUAPL/SwRI
I find the hazes the most amazing aspect of the photos. They remind me of crepuscular rays, those beams of sunshine that shine between breaks in the clouds near sunset and sunrise. It chills and thrills me to the bone to see such earthly sights on a bitterly cold orb more than 3 billion miles from home.
Ice, probably frozen nitrogen, appears to have accumulated on the uplands on the right side of this 390-mile (630-km) wide image is draining from Pluto’s mountains onto the informally named Sputnik Planum through the 2- to 5-mile (3- to 8-km) wide valleys indicated by the red arrows. On Earth this would be considered a valley glacier. The flow front of the ice moving into Sputnik Planum is outlined by the blue arrows. The origin of the ridges and pits on the right side of the image remains uncertain. Credits: NASA/JHUAPL/SwRI
But that’s not all that’s close to our hearts on Pluto. The photos reveal nitrogen ice apparently flowing downhill from mountainous highlands into a broad, smooth basin. Combined with other recently downloaded pictures, this new image (above) provides evidence for a remarkably Earth-like “hydrological” cycle on Pluto – but involving soft and exotic ices, including nitrogen, rather than water ice.
This might be the most remarkable image of all. It covers the same region as the image above, but is re-projected from the oblique, backlit view shown in the new crescent image of Pluto. The backlighting highlights the intricate flow lines on the valley glaciers. The flow front of the ice moving into the informally named Sputnik Planum is outlined by the blue arrows. We’re looking at a scene 390 miles (630 km) across. Credits: NASA/JHUAPL/SwRI
Nitrogen ice in the vast, relatively smooth Sputnik Planum may have vaporized in sunlight and then redeposited as ice in the bright, rugged region to its east. The new Ralph imager panorama also reveals glaciers flowing back from the blanketed mountain region into Sputnik Planum; these features are similar to the frozen streams on the margins of ice caps on Greenland and Antarctica.
Who knew that by going to Pluto we’d see such familiarity? But there you have it.
It now covers 9 years (9 animation frames) from 2007 to 2015 (July). Nothing much has changed but for its location keeps moving north. For those looking to find it visually the arrowhead asterism to the south seen in the full frame image which is about a half degree wide and a third of a degree high. so fits a medium power telescope field of view. The galaxy near the bottom of the image is CGCG 056-003, a 15.6 magnitude galaxy some 360 million light-years distant and 85,000 light-years across. Credit: Rick Johnson
Tucked away in northern Ophiuchus and well-placed for observing from spring through fall is one of the most remarkable objects in the sky — Barnard’s Star. A magnitude +9.5 red dwarf wouldn’t normally catch our attention were it not for the fact that it speeds across the sky faster than any other star known.
Incredibly, you can actually see its motion with a small telescope simply by dropping by once a year for 2-3 years and taking note of its position against the background stars. For one amateur astronomer, recording its wandering ways became a 9-year mission.
This map shows the sky facing south-southwest around 9 o’clock local time in late September. Barnard’s Star is located 1° NW of the 4.8-magnitude star 66 Ophiuchi on the northern fringe of the loose open cluster Melotte 186. Use the more detailed map below to pinpoint the star’s location. Source: Stellarium
Located just 6 light years from Earth, making it the closest star beyond the Sun except for the Alpha Centauri system, Barnard’s Star dashes along at 10.3 arc seconds a year. OK, that doesn’t sound like much, but over the course of a human lifetime it moves a quarter of a degree or half a Full Moon, a distance large enough to be easily perceived with the naked eye.
Barnard’s Star is a very low mass red dwarf star 1.9 times Jupiter’s diameter only 6 light-years from Earth in the direction of the constellation Ophiuchus the Serpent Bearer. Credit: Wikipedia with additions by the author
This fleet-footed luminary was first spotted by the American astronomer E.E. Barnard in 1916. With a proper motion even greater than the triple star Alpha Centauri, we’ve since learned that the star’s speed is truly phenomenal; it zips along at 86 miles a second (139 km/sec) relative to the Sun. As the stellar dwarf moves north, it’s simultaneously headed in our direction.
Based on its high velocity and low “metal” content, Barnard’s Star is believed to be a member of the galactic bulge, a fastness of ancient stars formed early on in the Milky Way galaxy’s evolution. Metals in astronomy refer to elements heavier than hydrogen and helium, the fundamental building blocks of stars. That’s pretty much all that was around when the first generation of suns formed about 100 million years after the Big Bang.
Generally, the lower a star’s metal content, the more ancient it is as earlier generations only had the simplest elements on hand. More complex elements like lithium, carbon, oxygen and all the rest had to be cooked up the earliest stars’ interiors and then released in supernovae explosions where they later became incorporated in metal-rich stars like our Sun.
All this to say that Barnard’s Star is an interloper, a visitor from another realm of the galaxy here to take us on a journey across the years. It certainly got the attention of Lincoln, Nebraska amateur Rick Johnson, who first learned of the famous dwarf in 1957.
Close-up map showing Barnard’s Star’s position every 5 years from 2015 to 2030. Your guide star, 66 Ophiuchi, also shown on the first map, is at lower left. Stars are numbered with magnitudes and a 15 arc minute scale bar is at lower right. North is up. The line through the two 12th-magnitude stars will help you gauge Barnard’s movement in the coming few years. Click for a larger map.
“One of the first things I imaged was Barnard’s Star on the off chance I could see its motion,” wrote Johnson, who used a cheap 400mm lens on a homemade tracking mount. “Taking it a couple months later didn’t show any obvious motion, though I thought I saw it move slightly. So I took another image the following year and the motion was obvious.”
Many years later in 2005, Johnson moved to very dark skies, upgraded his equipment and purchased a good digital camera. Barnard’s Star continued to tug at his mind.
“Again one of my first thoughts was Barnard’s Star. The idea of an animation however didn’t hit until later, so my exposure times were all over the map. This made the first frames hard to match.” Later, he standardized the exposures and then assembled the individual images into a color animation.
This diagram illustrates the locations of the star systems closest to the Sun along with the dates of discovery. NASA’s Wide-field Infrared Survey Explorer, or WISE, found two of the four closest systems: the binary brown dwarf WISE 1049-5319 and the brown dwarf WISE J085510.83-071442.5. The closest system to the Sun is a trio of stars that consists of Alpha Centauri, a close companion to it and Proxima Centauri. Credit: NASA / Penn State
“Now the system is programed to take it each July,” he added. I’m automated, so its all automatic now.” Johnson said the Barnard video is his most popular of many he’s made over the years including short animations of the eye-catching Comet C/2006 M4 SWAN and Near-Earth asteroid 2005 YU55.
With Johnson’s wonderful animation in your mind’s eye, I encourage you to use the maps provided to track down the star yourself the next clear night. To find it, first locate 66 Ophiuchi (mag. 4.8) just above the little triangle of 4th magnitude stars a short distance east or left of Beta Ophiuchi. Then use the detailed map to star hop ~1° to the northwest to Barnard’s Star.
Barnard’s Star, a red dwarf low in metals, is very ancient with an age between 7 and 12 billion years. Like people, older stars slow down and Barnard’s is no exception with a rotation rate of 150 days. Heading in the Sun’s direction, the star will come closest to our Solar System around the year 11,800 A.D. at a distance of just 3.75 light years. Credit: NASA
It’s easily visible in a 3-inch or larger telescope. Use as high a magnification as conditions will allow to make a sketch of the star’s current position, showing it in relation to nearby field stars. Or take a photograph. Next summer, when you return to the field, sketch it again. If you’ve taken the time to accurately note the star’s position, you might see motion in just a year. If not, be patient and return the following year.
Most stars are too far away for us to detect motion either with the naked eye or telescope in our lifetime. Barnard’s presents a rare opportunity to witness the grand cycling of stars around the galaxy otherwise denied our short lives. Chase it.
The Moon, just a couple days before new phase and the upcoming partial solar eclipse, joins Venus and Mars in the dawn sky on Thursday Sept. 10. Well below the triplet, look for returning Jupiter. Source: Stellarium
The dawn sky’s where it’s happening. With Saturn swiftly sinking westward at dusk, bright planets have become scarce in the evening hours. But if you get up early and look east, you’ll discover where the party is. Venus, Mars and now Jupiter have the dance floor.
Tale of two crescents. A montage of the thick crescent Moon and crescent Venus photographed earlier this month. Credit: Tom Ruen
What’s more, the sky gods have seen fit to roll a thin crescent Moon alongside Venus Thursday morning (Sept. 10). This lovely twinning of crescents is best seen about 75 minutes to an hour before sunrise. All you need is a pair of 10x binoculars to see the peewee Venusian version. Its waning crescent phase closely mimics the Moon’s.
From the U.S., the separation between the two will vary from 3° for the East Coast to 4.5° for the West. European and African skywatchers will witness the actual conjunction with the Moon gliding 2.5° north of the planet.
Venus is very bright, making it easy to see in the daytime if you know where to look. Try using the thin Moon soon after sunrise (7:30 a.m. local time shown here) to spot Venus. Aim and focus your binoculars on the Moon, then glide up and to the right to find Venus. If you succeed, lower the binoculars and see if you can spot it without optical aid. Source: Stellarium
Much fainter Mars, checking in at magnitude +1.8, lies 6° to the left or east of the Moon. It thrills me to see Mars begin a new apparition with its return to the morning sky. Next year, the Red Planet reaches opposition on May 22 in the constellation Scorpius, when it will be brighter than Sirius and more than 18 arc seconds across, its biggest and closest since 2005.
Remember Jupiter? We lost it in the solar glare more than a month ago, but if you can find a location with a nice, open eastern horizon, you can welcome the ever-jovial planet back Thursday. Bring binoculars just in case! Jove’s only a few degrees high in moderately-bright twilight.
The bright sunlit crescent contrasts with the darker lighting of twice-reflected light contributed by own planet. Credit: Bob King
When you look at the Moon Thursday, most of it will be illuminated not by sunlight but by Earth-light called earthshine. This smoky, dark glow results from sunlight bouncing off the globe into space to softly light the otherwise shadowed portion of the Moon. The effect is most pleasing to the eye and remarkable in binoculars, which reveal lunar seas and even larger craters shrouded in blue-dark. Don’t miss it!
The Full Moon at 10:30 p.m. last night (Aug. 30). Even at 25 altitude, it glowed a deep, dark orange due to heavy smoke from western forest fires. Credit: Bob King
Did you see the Moon last night? I walked outside at 10:30 p.m. and was stunned to see a dark, burnt-orange Full Moon as if September’s eclipse had arrived a month early. Why? Heavy smoke from forest fires in Washington, California and Montana has now spread to cover nearly half the country in a smoky pall, soaking up starlight and muting the moonlight.
If this is what global warming has in store for us, skywatchers will soon have to take a forecast of “clear skies” with a huge grain of salt.
The Pacific Northwest is abundantly dotted with wildfires in Washington, Oregon, Idaho and Montana in this Aqua satellite image taken on August 25, 2015. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red. Smoke from the fires has been drifting east, blanketing Midwestern skies and blotting out the stars at night. Credit: NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team
By day, the sky appears the palest of blues. By night, the stars are few if any, and the Moon appears faint, the color of fire and strangely remote. Despite last night’s clear skies, only the star Vega managed to penetrate the gloom. I never saw my shadow even at midnight when the Moon had climbed high into the southern sky.
Last night’s Full Moon seen through an 8-inch telescope at 11:30 p.m. The colors are true. Credit: Bob King
We’ve seen this smoke before. Back in July, Canadian forest fires wafted south and west and covered much of the northern half of the U.S., giving us red suns in the middle of the afternoon and leaving only enough stars to count with two hands at night. On the bright side, the Moon is fascinating to observe. I set up the telescope last night and spend a half hour watching this unexpected “eclipse”; sunsets appear positively atomic. The size of the smoke particles is just right for filtering out or scattering away blues, greens and even yellow from white light. Vivid reds, pinks and oranges remain to tint anything bright enough to penetrate the haze.
GOES-8 satellite view of the central U.S. taken at 8:15 a.m. CDT August 30, 2015 show a veil of grayish forest fire smoke covering much of the Midwest with clearer conditions to the southeast. The red line is the approximate border between the two. Credit: NOAA
But smoke can cause harm, too. Forest fire smoke contains carbon monoxide, carbon dioxide and soot. On especially smoky days, you can even smell the odor of burning trees in the air at ground level. Some may suffer from burning eyes, asthma or bronchitis on especially smoky days even a thousand miles from the source fires.
Wide-angle view of last night’s Moon. Notice that the smoke is thicker along the horizontal – left and right of the Moon. Above, at a higher elevation, we see through less smoke, so the moonlit sky is a bit brighter there. No stars are visible. Credit: Bob King
On clear, blue-sky days, I’ve watched the smoke creep in from the west. It begins a light haze and slowly covers the entire sky in a matter of several hours, often showing a banded structure in the direction of the Sun. A little smoke is OK for observing, but once it’s thick enough to redden the Moon even hours after moonrise, you can forget about using your telescope for stargazing. Sometimes, a passing thunderstorm and cold front clears the sky again. Sometimes not.
The only cures for fire soot are good old-fashioned rain and the colder weather that arrives with fall. In the meantime, many of us will spend our evenings reading about the stars instead of looking at them.
A Full Moon in all its horizontal glory. When near the horizon, refraction squeezes the lunar disk into an oval. Scattering removes the shorter wavelengths of white light, leaving the Moon a rich red or orange. Credit: Bob King
Who doesn’t love a Full Moon? Occurring about once a month, they never wear out their welcome. Each one becomes a special event to anticipate. In the summer months, when the Moon rises through the sultry haze, atmosphere and aerosols scatter away so much blue light and green light from its disk, the Moon glows an enticing orange or red.
At Full Moon, we’re also more likely to notice how the denser atmosphere near the horizon squeezes the lunar disk into a crazy hamburger bun shape. It’s caused by atmospheric refraction. Air closest to the horizon refracts more strongly than air near the top edge of the Moon, in effect “lifting” the bottom of the Moon up into the top. Squished light! We also get to see all the nearside maria or “seas” at full phase, while rayed craters like Tycho and Copernicus come into their full glory, looking for all the world like giant spatters of white paint even to the naked eye.
At full phase, the Moon lies directly opposite the Sun on the other side of Earth. Sunlight hits the Moon square on and fully illuminates the Earth-facing hemisphere. Credit: Bob King
Tomorrow night (August 29), the Full Sturgeon Moon rises around sunset across the world. The name comes from the association Great Lakes Indian groups made between the August moon and the best time to catch sturgeon. Next month’s moon is the familiar Harvest Moon; the additional light it provided at this important time of year allowed farmers to harvest into the night.
A Full Moon lies opposite the Sun in the sky exactly like a planet at opposition. Earth is stuck directly between the two orbs. As we look to the west to watch the Sun go down, the Moon creeps up at our back from the eastern horizon. Full Moon is the only time the Moon faces Sun directly – not off to one side or another – as seen from Earth, so the entire disk is illuminated.
The moon provides the perfect backdrop for watching birds migrate at night. Although a small telescope is best, you might see an occasional bird in binoculars, too. Credit: Bob King
If you’re a moonrise watcher like I am, you’ll want to find a place where you can see all the way down to the eastern horizon tomorrow night. You’ll also need the time of moonrise for your city and a pair of binoculars. Sure, you can watch a moonrise without optical aid perfectly well, but you’ll miss all the cool distortions happening across the lunar disk from air turbulence. Birds have also begun their annual migration south. Don’t be surprised if your glass also shows an occasional winged silhouette zipping over those lunar seas.
Because the Moon’s orbit is tilted 5.1° with respect to Earth’s, it normally passes above or below Earth’s shadow with no eclipse — either lunar or solar. Only when the lineup is exact, does the Moon pass directly behind Earth and into its shadow. Credit: Bob King
Next month’s Full Moon is very special. A few times a year, the alignment of Sun, Earth and Moon (in that order) is precise, and the Full Moon dives into Earth’s shadow in total eclipse. That will happen overnight Sunday night-Monday morning September 27-28. This will be the final in the current tetradof four total lunar eclipses, each spaced about six months apart from the other. I think this one will be the best of the bunch. Why?
The totally eclipsed moon on April 15, 2014 from Duluth, Minn. This was the first in the series of four eclipses called a tetrad. September’s totally eclipsed Moon will appear similar. The coloring comes from sunlight grazing the edge of Earth’s atmosphere and refracted by it into the planet’s shadow. Credit: Bob King
Convenient evening viewing hours (CDT times given) for observers in the Americas. Partial eclipse begins at 8:07 p.m., totality lasts from 9:11 – 10:23 p.m. and partial eclipse ends at 11:27 p.m. Those times mean that for many regions, kids can stay up and watch.
The Moon passes more centrally through Earth’s shadow than during the last total eclipse. That means a longer totality and possibly more striking color contrasts.
September’s will be the last total eclipse visible in the Americas until January 31, 2018. Between now and then, there will be a total of four minor penumbral eclipses and one small partial. Slim pickings.
Diagram showing the details of the upcoming total lunar eclipse. The event begins when the Moon treads into Earth’s outer shadow (penumbra) at 7:12 p.m. CDT. Partial phases start at 8:07 and totality at 9:11. Credit: NASA / Fred Espenak
Not only will the Americas enjoy a spectacle, but totality will also be visible from Europe, Africa and parts of Asia. For eastern hemisphere skywatchers, the event will occur during early morning hours of September 28. Universal or UT times for the eclipse are as follows: Partial phase begin at 1:07 a.m., totality from 2:11 – 3:23 a.m. with the end of partial phase at 4:27 a.m.
September 27-28, 2015 eclipse visibility map. Credit: NASA / Fred Espenak
We’ll have much more coverage on the upcoming eclipse in future articles here at Universe Today. I hope this brief look will serve to whet your appetite and help you anticipate what promises to be one of the best astronomical events of 2015.
This sequence of images, taken with Rosetta's OSIRIS narrow-angle camera on 30 July 2015, show a boulder-sized object close to the nucleus of Comet 67P/Churyumov-Gerasimenko.
The images were captured on 30 July 2015, about 185 km from the comet. The object measures between one and 50 m across; however, the exact size cannot be determined as it depends on its distance to the spacecraft, which cannot be inferred from these images. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
How would you like to see one of the most famous comets with your own eyes? Comet 67P/Churyumov-Gerasimenko plies the morning sky, a little blot of fuzzy light toting an amazing visitor along for the ride — the Rosetta spacecraft. When you look at the coma and realize a human-made machine is buzzing around inside, it seems unbelievable.
Comet 67P/Churyumov-Gerasimenko plows through a rich star field in Gemini on the morning of August 20, 2015. Photos show a short, faint tail to the west not visible to the eye in most amateur telescopes. Credit: Efrain Morales
If you have a 10-inch or larger telescope, or you’re an experienced amateur with an 8-inch and pristine skies, 67P is within your grasp. The comet glows right around magnitude +12, about as bright as it will get this apparition. Periodic comets generally appear brightest around and shortly after perihelion or closest approach to the Sun, which for 67P/C-G occurred back on August 13.
The surface of Comet 67P/C-G is extensively fractured due to loss of volatile ices, the expansion and contraction of the comet from solar heating and bitter cold and possibly even tectonic forces. The smaller polygonal shapes outlined by fractures in the lower right photo are just 6-16 feet (2-5 meters) across. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
You’ll be looking for a small, 1-arc-minute-diameter, compact, circular patch of nebulous light shortly before dawn when it’s highest in the east. Rosetta’s Comet will spend the remainder of August slicing across Gemini the Twins north of an nearly parallel to the ecliptic. I spotted 67P/C-G for the first time this go-round about a week ago in my 15-inch (37 cm) reflector. While it appears like a typical faint comet, thanks to Rosetta, we know this particular rough and tumble mountain of ice better than any previous comet. Photographs show rugged cliffs, numerous cracks due to the expansion and contraction of ice, blowholes that serve as sources for jets and smooth plains blanketed in fallen dust.
Geysers of dust and gas shooting off the comet’s nucleus are called jets. The material they deliver outside the nucleus builds the comet’s coma. Credit: ESA/Rostta/NAVCAM
The jets are geyser-like sprays of dust and gas that loft grit and rocks from the comet’s interior and surface into space to create a coma or temporary atmosphere. This is what you’ll see in your telescope. And if you’re patient, you’ll even be able to catch this glowing tadpole on the move. I was surprised at its speed. After just 20 minutes, thanks to numerous field stars that acted as references, I could easily spot the comet’s eastward movement using a magnification of 245x.
Facing east around 4 a.m. local time in late August, you’ll see the winter constellations Gemini and Orion. 67P/C-G’s path is shown through early September. Brighter stars near the path are labeled. Time shown is 4 a.m. CDT. Use this map to get oriented and then switch to the one below for telescope use. Source: Chris Marriott’s SkyMap
Tomorrow morning, 67P/C-G passes very close to the magnitude +5 star Omega Geminorum. While this will make it easy to locate, the glare may swamp the comet. Set your alarm for an hour before dawn’s start to allow time to set up a telescope, dark-adapt your eyes and track down the field where the comet will be that morning using low magnification.
Once you’ve centered 67P/C-G’s position, increase the power to around 100x-150x and use averted vision to look for a soft, fuzzy patch of light. If you see nothing, take it to the next level (around 200-250x) and carefully search the area. The higher the magnification, the darker the field of view and easier it will be to spot it.
Detailed map showing the comet’s path through central Gemini daily August 21-28, 2015 around 4 a.m. CDT. Brighter stars are marked with Greek letters and numbers. “57”= 57 Geminorum. North is up, east to the left and stars to magnitude +13.5. Click for a larger version you can print out. Source: Chris Marriott’s SkyMap
Besides being relatively faint, the comet doesn’t get very high in the east before the onset of twilight. Low altitude means the atmosphere absorbs a share of the comet’s light, making it appear even fainter. Not that I want to dissuade you from looking! There’s nothing like seeing real 67P photons not to mention the adventure and sense of accomplishment that come from finding the object on your own.
As we advance into late summer and early fall, 67P/C-G will appear higher up but also be fading. Now through about August 27 and again from September 10-24 will be your best viewing times. That’s when the Moon’s absent from the sky.
Given the comet’s current distance from Earth of 165 million miles and apparent visual size of just shy of 1 arc minute, the coma measures very approximately 30,000 miles across. Rosetta orbits the comet’s 2.5-mile-long icy nucleus at a distance of about 115 miles (186 km), meaning it’s snug up against the nuclear center from our point of view on the ground.
