Comet ISON: A Viewing Guide from Now to Perihelion

Perhaps you’ve read the news. This Fall, the big ticket show is the approach of Comet C/2012 S1 ISON. The passage of this comet into the inner solar system has been the most anticipated apparition of a comet since Hale-Bopp in 1997.

Many backyard observers will get their first good look at Comet ISON in the coming month. If you want to see this comet for yourself, here’s everything you’ll need to know!

(Credit: HubbleSite.org/Go/ISON).
A composite image of Comet ISON as seen from the Hubble Space Telescope on April 30th, 2013. (Credit: HubbleSite.org/Go/ISON).

Discovered on September 21st, 2012 by Artyom-Kislovodsk and Vitaly Nevsky using the International Scientific Optical Network’s (ISON) 0.4 metre reflector, this comet has just passed out from behind the Sun from our Earthly vantage point this summer to once again become visible in the dawn sky.

Of course, there’s much speculation as to whether this will be the “comet of the century” shining as “bright as the Full Moon” near perihelion. We caught up with veteran comet observer John Bortle earlier this year to see what skywatchers might expect from this comet in late 2013. We’ve also chronicled the online wackiness of comets past and present as ISON makes its way into the pantheon as the most recently fashionable scapegoat for “the end of the world of the week…”

But now it’s time to look at the astronomical prospects for observing Comet ISON, and what you can expect leading up to perihelion on November 28th.

Comet ISON imaged by Efrain Morales on September 22nd. (Credit: Efrain Morales/Jaicoa Observatory, used with permission).
Comet ISON as recently imaged by Efrain Morales on September 22nd. (Credit: Efrain Morales/Jaicoa Observatory, used with permission).

Advanced amateur astronomers are already getting good images of Comet ISON, which currently shines at around +12th magnitude in the constellation Cancer. And although NASA’s Deep Impact/EPOXI mission is down for the count, plans are afoot for the Curiosity rover and the Mars Reconnaissance Orbiter to attempt imaging the comet when it makes its closest approach to the Red Planet on October 1st at 0.0724 Astronomical Units (A.U.) or 10,830,000 kilometres distant. If MSL is successful, it would be the first time that a comet has been observed from the surface of another world.

Currently, ISON sits about a magnitude below the projected light curve, (see below) but that isn’t all that unusual for a comet. Already, there’s been increasing talk of “ISON being a dud,” but as Universe Today’s Nancy Atkinson pointed out in a recent post, these assertions are still premature. The big question is what ISON will do leading up to perihelion, and if it will survive its passage 1.1 million kilometres above the surface of the Sun on November 28th to become a fine comet in the dawn skies in the weeks leading up to Christmas.

ISON is already starting to show a short, spikey tail in amateur images. Tsutomu Seki estimated it to be shining at about magnitude +11.1 on September 16th. Keep in mind, a caveat is in order when talking about the magnitudes of comets. Unlike stars, which are essentially a point source, the brightness of a comet is spread out over a large surface area. Thus, a comet may appear visually fainter than the quoted magnitude, much like a diffuse nebula. Although +6th magnitude is usually the limit for naked eye visibility, I’ll bet that most folks won’t pick up ISON with the unaided eye from typical suburban sites until it breaks +4th magnitude or so.

(Credit: NASA CIOC/Matthew Knight. used with permission).
The recent revised light curve projected for Comet ISON (Credit: NASA CIOC/Compiled by Matthew Knight of the Lowell Observatory).

The forward scattering of light also plays a key role in the predicted brightness of a comet. The November issue of Astronomy Magazine has a great article on this phenomenon. It’s interesting to note that ISON stacks up as a “9” on their accumulated point scale, right at the lower threshold of comet “greatness,” versus a 15 for sungrazing Comet C/1965 S1 Ikeya-Seki. Another famous “9” was Comet C/1996 B2 Hyakutake, which passed 0.1018 A.U. or 15.8 million kilometres from Earth on March 25, 1996.

ISON will pass 0.429 A.U. or 64.2 million kilometres from Earth the day after Christmas. Bruce Willis can stay home for this one.

Here is a blow-by-blow breakdown of some key dates to watch for as ISON makes its plunge into the inner solar system:

-September 25th: ISON crosses the border from the astronomical constellation of Cancer into Leo.

-September 27th: ISON passes 2 degrees north of the planet Mars.

The path of Comet ISON from October 1st to November 21st. The position of the Sun is shown on the final date. (Created by the Author using Starry Night Education software).
The path of Comet ISON from October 1st to November 21st. The position of the Sun is shown on the final date. (Created by the Author using Starry Night Education software).

-October 1st: The 12% illuminated waning crescent Moon passes 10 degrees south of Mars & ISON.

-Early October: ISON may break +10th magnitude and become visible with binoculars or a small telescope.

-October 4th: New Moon occurs. The Moon then exits the dawn sky, making for two weeks of prime viewing.

October 10th: ISON enters view of NASA’s STEREO/SECCHI HI-2A CAMERA:

Credit: NASA/ISON Observing campaign)
The path of ISON as it enters the view of STEREO. Credit: NASA/ISON Observing campaign)

-October 16th: ISON passes just 2 degrees NNE of the bright star Regulus, making a great “guidepost” to pin it down with binoculars.

-October 18th: The Full Moon occurs, after which the Moon enters the morning sky.

-October 26th: A great photo-op for astro-imagers occurs, as ISON passes within three degrees the Leo galaxy trio of M95, M96, & M105.

The position of Comet ISON on October 26th in Leo. (Created by the author in Stellarium).
The position of Comet ISON on October 26th in Leo near Mars and a trio of galaxies. (Created by the author in Stellarium).

-October 30th: The 17% illuminated Moon passes 6 degrees south of ISON.

-Early November: Comet ISON may make its naked eye debut for observers based at dark sky sites.

-November 3rd: A hybrid (annular-total) solar eclipse occurs, spanning the Atlantic and Central Africa. It may just be possible for well placed observers to catch sight of ISON in the daytime during totality, depending on how quickly it brightens up. The Moon reaching New phase also means that the next two weeks will be prime view time for ISON at dawn.

-November 5th: ISON crosses the border from the astronomical constellation of Leo into Virgo.

-November 7th: ISON passes less than a degree from the +3.6 magnitude star Zavijava (Beta Virginis).

-November 8th: ISON passes through the equinoctial point in Virgo around 16:00 EDT/20:00 UT, passing into the southern celestial hemisphere and south of the ecliptic.

-November 14th: ISON passes less than a degree from the 10th magnitude galaxy NGC 4697.

-November 17th: The Moon reaches Full, passing into the morning sky.

-November 18th: ISON passes just 0.38 degrees north of the bright star Spica.

-November 22nd: ISON crosses into the astronomical constellation of Libra.

-November 23rd: ISON sits 4.7 degrees SSW of the planet Mercury and 4.9 SSW of Saturn, respectively.

Looking east before dawn on the morning of November 23rd. (Created by the author using Starry Night Education software).
Looking east before dawn on the morning of November 23rd. Note comet 2P/Encke nearby! (Created by the author using Starry Night Education software).

-November 25th: ISON pays a visit to another famous comet, passing just 1.2 degrees south of short period comet 2P/Encke which may shine at +8th magnitude.

-November 27th: ISON enters the field of view of SOHO’s LASCO C3 coronagraph.

-November 28th: ISON reaches perihelion at ~18:00 PM EST/ 23:00 UT.

After that, all bets are off. The days leading up to perihelion will be tense ones, as ISON then rounds the Sun on a date with astronomical destiny. Will it join the ranks of the great comets of the past? Will it stay intact, or shatter in a spectacular fashion? Watch this space for ISON updates… we’ll be back in late November with our post-perihelion guide!

Be sure to also enjoy recently discovered Comet C/2013 R1 Lovejoy later the year.

Got ISON pics? Send ’em in to Universe Today!

 

An Unexpected Ending for Deep Impact

After almost 9 years in space that included an unprecedented July 4th impact and subsequent flyby of a comet, an additional comet flyby, and the return of approximately 500,000 images of celestial objects, NASA’s Deep Impact/EPOXI mission has officially been brought to a close.

The project team at NASA’s Jet Propulsion Laboratory has reluctantly pronounced the mission at an end after being unable to communicate with the spacecraft for over a month. The last communication with the probe was Aug. 8. Deep Impact was history’s most traveled comet research mission, having journeyed a total of about 4.7 billion miles (7.58 billion kilometers).

“Deep Impact has been a fantastic, long-lasting spacecraft that has produced far more data than we had planned,” said Mike A’Hearn, the Deep Impact principal investigator at the University of Maryland in College Park. “It has revolutionized our understanding of comets and their activity.”

Artist's rendering of the Deep Impactor flyby spacecraft (NASA)
Artist’s rendering of the Deep Impactor flyby spacecraft (NASA)

Launched in January 2005, the spacecraft first traveled about 268 million miles (431 million kilometers) to the vicinity of comet Tempel 1. On July 3, 2005, the spacecraft deployed an impactor into the path of comet to essentially be run over by its nucleus on July 4. This caused material from below the comet’s surface to be blasted out into space where it could be examined by the telescopes and instrumentation of the flyby spacecraft.  Sixteen days after that comet encounter, the Deep Impact team placed the spacecraft on a trajectory to fly back past Earth in late December 2007 to put it on course to encounter another comet, Hartley 2 in November 2010, thus beginning the spacecraft’s new EPOXI mission.

“Six months after launch, this spacecraft had already completed its planned mission to study comet Tempel 1,” said Tim Larson, project manager of Deep Impact at JPL. “But the science team kept finding interesting things to do, and through the ingenuity of our mission team and navigators and support of NASA’s Discovery Program, this spacecraft kept it up for more than eight years, producing amazing results all along the way.”

The spacecraft’s extended mission culminated in the successful flyby of comet Hartley 2 on Nov. 4, 2010. Along the way, it also observed six different stars to confirm the motion of planets orbiting them, and took images and data of the Earth, the Moon and Mars. These data helped to confirm the existence of water on the Moon, and attempted to confirm the methane signature in the atmosphere of Mars.  One sequence of images is a breathtaking view of the Moon transiting across the face of Earth.

This image of comet ISON C/2012 S1 from NASA’s Deep Impact/EPOXI  spacecraft clearly shows the coma and nucleus on Jan. 17 and 18, 2013 beyond the orbit of Jupiter. Credit: NASA.
This image of comet ISON C/2012 S1 from NASA’s Deep Impact/EPOXI spacecraft clearly shows the coma and nucleus on Jan. 17 and 18, 2013 beyond the orbit of Jupiter. Credit: NASA.

The spacecraft’s extended mission culminated in the successful flyby of comet Hartley 2 on Nov. 4, 2010. In January 2012, Deep Impact performed imaging and accessed the composition of distant comet C/2009 P1 (Garradd).

It took images of comet ISON this year and collected early images of comet ISON in June.

After losing contact with the spacecraft last month, mission controllers spent several weeks trying to uplink commands to reactivate its onboard systems. Although the exact cause of the loss is not known, analysis has uncovered a potential problem with computer time tagging that could have led to loss of control for Deep Impact’s orientation. That would then affect the positioning of its radio antennas, making communication difficult, as well as its solar arrays, which would in turn prevent the spacecraft from getting power and allow cold temperatures to ruin onboard equipment, essentially freezing its battery and propulsion systems.

Without battery power, the Deep Impact spacecraft is now adrift and silent, spinning out of control through the solar system.

Launch of Deep Impact aboard a Boeing Delta II from Cape Canaveral AFB on Jan. 12, 2005 (NASA)
Launch of Deep Impact aboard a Boeing Delta II rocket from Cape Canaveral AFS on Jan. 12, 2005 (NASA)

“Despite this unexpected final curtain call, Deep Impact already achieved much more than ever was envisioned. Deep Impact has completely overturned what we thought we knew about comets and also provided a treasure trove of additional planetary science that will be the source data of research for years to come.”

– Lindley Johnson, Program Executive for the Deep Impact mission

It’s a sad end for a hardworking spacecraft, but over the course of its 8 1/2 years in space Deep Impact provided many significant results for the science community. Here are the top five, according to the mission’s principal investigator Michael A’Hearn.

Read more about the Deep Impact mission here.

Source: NASA press release

More ISON Craziness: Tales of Popes, a Prophet and a Comet

There’s an astronomical tall tale from the Middle Ages that seems to get recycled as factual every time a “great” comet rolls around. This week, we thought we’d look at a story that just won’t die, as well as a new twist in comet conspiracy that’s rolling around ye’ ole ‘Net.

We’ve debunked the current craziness surrounding ISON recently, but apparently our work isn’t finished! Comets seem to bring ‘em out of the woodwork. Today, we’ll discuss how that old prophet of doom Nostradamus may have “predicted” Comet ISON being part of the ‘end times,’ but first, let’s look at an astronomical tale of the past. Did a pope really excommunicate the most famous of all comets?

The mid-15th century was a trying time for Medieval Europe. The Black Death  had decimated the population of Europe a century prior, and the armies of the Ottoman Turks were advancing from the east. A bright comet could only bear ill will in the minds of the superstitious.

Pope Callixtus III: the ecommunicator of comets? (Credit:  Museo de la Catherdral de Valencia).
Pope Callixtus III: the excommunicator of comets? (Credit: Museo de la Cathedral de Valencia).

It was into this setting that Pope Callixtus III came into power in 1455. Callixtus was the first of two popes fielded by the Spanish Borgia family, which would later include his nephew Rodrigo who became Pope Alexander the VI, as depicted in the Showtime series The Borgias.

A fine the apparition of Halley’s Comet occurred in June and July 1456. Belgrade was to come under siege by the Ottoman Turks from July 4th to 22nd of that year, and the Fall of Constantinople on May 29th, 1453 to Mehmed II was still fresh on everyone’s mind.

Astronomical signs and omens were a hot topic as well. The partial lunar eclipse of May 22nd, 1453 was seen by many to have fulfilled prophecy that an eclipse would mark the fall of Constantinople. Of course, there are from 4 to 7 eclipses that can be seen on any given year, and lunar eclipses are visible from the entire moonward facing side of the Earth. It’s not too tough to find one to fit any given bill of gloom and doom.

Keep in mind, Halley’s Comet wasn’t even identified in the 15th century as the same comet that was returning once every 75.3 years. That fact wouldn’t be uncovered until Edmund Halley successfully predicted the return of the comet that now bears his name on Christmas Day 1758.

Halley’s Comet would’ve been a spectacular sight in the early summer of 1456, unfurling a tail that was said to have been 60 degrees long and spanning the constellations of Cancer and Leo. The brilliant comet would’ve been a conspicuous object for up to three hours after sunset, and it’s certain that observers around the Mediterranean, including a Rome-based pope would’ve seen it.

A depiction of the passage of Comet Halley through the constellations of Cancer & Leo in 1456. (Wikimedia Commons image in the Public Domain).
A depiction of the passage of Comet Halley through the constellations of Cancer & Leo in 1456. (Wikimedia Commons image in the Public Domain).

But did the pope actually excommunicate the comet to assuage the fears of the European populace of an invasion from the east?

While a quixotic story, the idea that a pope could’ve banned a heavenly body from salvation is apocryphal as best. The Papal Bull issued by Callixtus III on June 29th, 1456 called for prayers and penance and the ringing of church bells in light of the cruelty visited upon Eastern Europe by invaders from the east, but makes no mention of the comet. In fact, no primary source for the tale exists.

The story seems to have gotten its start with a historian named Platina, who wrote a biography of Callixtus III in 1471. Here we find the appearance of:

“A hairy reddish comet appearing for several days… Callixtus, in order to avert the wrath of God, ordered processions to be held…”

No out right excommunication per se, but the Pope and the comet were now forever linked in the eye of history.

The pitched Battle of Nandorfehervar during the 1456 Siege of Belgrade. (Wikimedia Commons scan in the Public Domain).
The pitched Battle of Nandorfehervar during the 1456 Siege of Belgrade. (Painting by Rubens in the Public Domain).

French mathematician and astronomer Pierre-Simon Laplace later gave the excommunication tale a boost in the late 18th century, and further embellishment followed from astronomer François Arago writing in 1832.

Keep in mind, these are historical works written down some years after the fact, often translated from Latin to French to English—ideas such as LaPlace’s “conjurer la comete” can easily come across as to “exorcise” or “excommunicate” a comet. Also, political satire of popes, both alive and dead, was common after the start of the Protestant Reformation. Halley’s Comet also made a fine apparition in 1835, and Arago may have been looking for something to captivate the public with in anticipation.

But although this story was debunked over a century ago, it still makes its rounds. None other than Carl Sagan repeated the excommunication story in his book Comet (sorry Carl!) although he also notes that the tale is apocryphal. Although the story of the excommunication of Halley’s Comet has been debunked time and again, a search of the Internet reveals about an even split between the credulous and the skeptical.

But there is also a current mythos being born around Comet ISON, Pope Francis and Nostradamus on ye ole web. For the most part, it has to do with — you guessed it — the end of the world. As per the usual, great comets are harbingers of catastrophic events. Combine the words of Nostradamus with the fact that 2013 has been hyped as “The Year of the Comet,” along with Pope Benedict’s unusual resignation, and that equals The End of Time.

If you don’t believe me, search of Comet/ISON/Pope and see what turns up. The gist of the prophecy cites a quatrain stating that:

 “the great star for seven days shall burn

So nakedly clear like two suns appearing

The large dog all night howling

While the great Pontiff shall change his territory.”  

Of course, the quatrains of Nostradamus, like all prophecies, are suitably vague enough that they could be interpreted almost in whatever fashion suits the reader. And again, we’re looking at the old 16th century French translated into modern English.

And like eclipses, there are a handful of comets every year. Most reach binocular visibility, and a few may go on to become visible to the naked eye. We’ve already had two comets that crossed this threshold this year, comet C/2011 L4 PanSTARRS and C/2012 F6 Lemmon.

Comet ISON as seen from the Hubble Space Telescope- no popes were harmed in the taking of this image! (credit: NASA/ESA/STScI/AURA).
Comet ISON as seen from the Hubble Space Telescope… no popes were harmed or forced to flee in the taking of this image. (credit: NASA/ESA/STScI/AURA).

And Comet ISON’s “greatness” is still very much in question. Its currently only at 12th magnitude and probably won’t be a naked eye object until at least early November. And it certainly won’t have the appearance of a second Sun!

I’ll leave it to the armchair predictors of comet doom to decipher what “the large dog howling” even means.  The chief logical fallacy evoked by the adherents of Nostradamus is what is known as retrofitting— it’s easy to take a cryptically predicted disaster and find an earthquake, eclipse, and yes, even a comet that falls roughly near the given date.

Of course, if ISON kicks into high gear, then we could really be in for a grand show, along with an accompanying upswing in comet hysteria. And thus, the tireless vigilance against comet-mania continues. Hey, we’re all after “link juice” and the almighty SEO, right? Of course, the real harm comes when something like the 1997 Heaven’s Gate mass suicide, inspired by rumors of an alien spacecraft following comet Hale-Bopp occurs.

Halleys March 9 2062
Halley’s Comet as seen on the morning of March 9th, 2062. (Created by the author using Starry Night Education software).

In short, enjoy the show as ISON approaches, read the online tales of popes and comets past… but as rapper and surreptitious promoter of skepticism Chuck D of Public Enemy implores us, don’t believe the hype.

Maybe we’ll finally be an enlightened and rational species when Halley’s Comet pays us a visit again starting  in the summer of 2061 through the spring of 2062!

-For an exhaustive look at the myth of the excommunication of Halley’s Comet, Read An Historical Examination of the Connection of Callixtus III with Halley’s Comet published in 1910.

-To see a (mostly) woo free version of the current Comet ISON versus Pope Francis mythos, (with quatrains) check out this article from news.com.au. Hey, we sift through woo so you don’t have to!

New Comet Discovered: Lovejoy Will Add to “Comet Lineup” in Winter Skies

Move over Comet ISON. You’ve got company.  Australian amateur astronomer Terry Lovejoy, discoverer of three previous comets, including the famous, long-tailed sungrazer C/2011 W3 (Lovejoy), just added a 4th to his tally.

This new comet will add to a lineup of comets that should grace early November skies in the northern hemisphere: Comets ISON, Encke and now the new Lovejoy.

Comet C/2013 R1 Lovejoy photographed on Sept. 10. The comet is visible in larger amateur telescopes in September but may brighten to small scope visibility in November. Credit: Michael Jaeger
Comet C/2013 R1 Lovejoy photographed on Sept. 10. The comet is visible in larger amateur telescopes in September but may brighten to small scope visibility in November. Streak at right is a geostationary satellite. Credit: Michael Jaeger

The discovery of C/2013 R1 Lovejoy was announced on Sept. 9 after two nights of photographic observations by Lovejoy with an 8-inch (20 cm) Schmidt-Cassegrain reflector. When nabbed, the comet was a faint midge of about 14.5 magnitude crossing the border between Orion and Monoceros. Subsequent observations by other amateur astronomers peg it a bit brighter at 14.0 with a small, condensed coma.

Comet Lovejoy has a small, condensed coma (head) about 30 arc seconds across with a faint, short tail in this photo made on Sept. 8. Credit: Ernesto Guido and Nick Howes
Comet Lovejoy has a small, condensed coma (head) about 30 arc seconds across with a faint, short tail in this photo made on Sept. 8. Credit: Ernesto Guido and Nick Howes

Right now you’ll need a hefty telescope to catch a glimpse of Lovejoy’s latest, but come November the comet will glow at around 8th magnitude, making it a perfect target for smaller telescopes. At closest approach on the Nov. 23, Lovejoy will pass 38.1 million miles (61.3 million km) from Earth while sailing across the Big Dipper at a quick pace.

The comet is a faint 14th magnitude object just east of Orion's Belt in the dim constellation Monoceros the Unicorn. The map shows its position tomorrow morning Sept. 11 just before the  start of morning twilight. Stellarium
The comet is a faint 14th magnitude object just east of Orion’s Belt in the dim constellation Monoceros the Unicorn. The map shows its position tomorrow morning Sept. 11 just before the start of morning twilight. Stellarium

Mid to late November is also the time when Comet ISON, the current focus of much professional and amateur observation, will be at its brightest in the morning sky at around magnitude 2-3. Get ready for some busy nights at the telescope!

A graph showing the comet's predicted magnitude (subject to change) in red versus the comet's elongation or distance from the sun. You can see that it will up in a dark sky for a long time especially around the time when it's brightest. Credit: Ernesto Guido & Nick Howes
A graph showing the comet’s predicted magnitude (subject to change) in red versus the comet’s elongation or angular distance from the sun. You can see that it will up in a dark sky for a long time including around the time when it’s brightest. Credit: Ernesto Guido & Nick Howes

C/2013 R1 will whip by the sun on Christmas Day at a distance of 81 million miles (130.3 million km) and then return back to the deeps from whence it came.

The charts here give you a general idea of its location and path over the next couple months. As the comet crosses into small-scope territory in early November, I’ll provide maps for you to find it.

A graphic created by Stuart Atkinson showing the comet and planetary lineup that should be in the skies on November 9, 2013.
A graphic created by Stuart Atkinson showing the comet and planetary lineup that should be in the skies on November 9, 2013.

And as Stuart Atkinson noted on his website, Cumbrian Sky a great lineup should be in the northern hemisphere skies on November 9, 2013. From the left, Comet Encke will be magnitude 6, ISON should be at about magnitude 6 or 7; then Mars, followed by the new Comet Lovejoy, which will be still very faint at around magnitude 9, topped off by a bright Jupiter. The comets will not likely be of naked eye visibility, but this should be a great chance for astrophotographer to capture this lineup!

Comet Lovejoy is approaching the plane of the planets from down under. The diagram shows the comet's position today. Like many comets, Lovejoy's orbit is steeply inclined - in this case 62 degrees. Credit: NASA
Comet Lovejoy is approaching the plane of the planets from “down under” (lower right). The diagram shows the comet’s position today. Like many comets, Lovejoy’s orbit is steeply inclined – in this case 62 degrees. Credit: NASA

Welcome to an exciting time for comet lovers, and congratulations Terry on another great discovery!

No Images of Comet ISON from Deep Impact/EPOXI Spacecraft Due to Communication Loss

Disappointing news today from Dr. Mike A’Hearn, Principal Investigator of the EPOXI mission, which has been using the repurposed spacecraft from the Deep Impact mission to study comets. The spacecraft was going to take some much-anticipated images of Comet ISON, but apparently a communication problem has occurred and the images may have been lost or possibly never taken.

“We have not received any of our expected observations of comet ISON due to a spacecraft problem,” A’Hearn wrote in an update on the EXPOXI website. “Communication with the spacecraft was lost some time between August 11 and August 14 (we only talk to the spacecraft about once per week). The last communication was on August 8. After considerable effort, the team on August 30 determined the cause of the problem. The team is now trying to determine how best to try to recover communication.”

No additional information was provided about the cause of the problem, however.

The Deep Impact mission intentionally crashed an impactor into comet Tempel-1 on July 4, 2005. Since then, EPOXI — the name comes from two combined missions to re-use the observing spacecraft, the Extrasolar Planet Observations and Characterization (EPOCh) and the Deep Impact Extended Investigation (DIXI) — has gone on to study comet Hartley 2, performing a close fly-by in 2010, studied C/2009 P1 (Garradd) in 2012, and has continued to be used as a remote observatory for studying comets.

EPOXI took images of Comet ISON on January 17, 2013, showing that the comet’s brightness varied on a timescale of hours (see the video above). There was another observing window from mid-February to March 8, where the team took infrared images of the comet.

The additional observing window from early July to early September is the timeframe for which there was a communication problem, and A’Hearn didn’t specify if any early images were received from the spacecraft, although he said they had “not received any of our expected observations.”

We’ll provide more information when it becomes available.

Ready, Set, Observe! How to See Comet ISON In The Early Morning Sky

OK, you’ve waited patiently for Comet ISON to brighten and  reappear in the dawn sky. It has. Now you’re chomping at the bit for a look at it in your telescope. Before you set the alarm and venture into the night, let’s prepare for what to expect. The better you know your target, the easier it will be to find.

Belgian astrophotographer Alfons Diepvens captured this view of ISON on Sept. 1, 2013 through his telescope. Tail length and direction are indicated. Click image to see more photos of ISON and other recent comets. Credit: Alfons Diepvens
Astrophotographer Alfons Diepvens captured this view of ISON on Sept. 1, 2013 through his telescope. Tail length and direction are indicated. Click image to see more his photos of ISON and other recent comets. Credit: Alfons Diepvens

The latest brightness estimates from the amateur comet community place ISON around magnitude 13, bright enough to be within reach of 10-inch (25 cm) and larger telescopes. Alan Hale of Arizona, co-discover of Comet Hale-Bopp, was one of the first to see it.  Through his 16-inch (41 cm) reflecting telescope  on September 1, he noted the comet as a small object about 0.6 arc minutes across (1 arc minute = 1/30 the diameter of the full moon), brighter in the center and shining faintly at magnitude 13.1. Picture a small, dim patch of glowing mist and you’ve got the picture. Hale’s observing conditions were excellent though he did have to contend with light from the nearby crescent moon. Starting tomorrow morning, the moon will finally be out of the picture.

This map shows the sky as you face east tomorrow morning  Sept. 3 around 5 a.m. local time just before the start of morning twilight. The comet is not far from Mars and the Beehive Cluster. Stellarium
With the moon out of the sky, now is a great time to hunt for Comet ISON. This map shows the sky as you face east tomorrow morning Sept. 3 around 5 a.m. local time just before the start of morning twilight. The comet is near both Mars and the Beehive Cluster. Stellarium

A sharp-eyed observer under the best skies would expect to see a fuzzy object this faint in a telescope as small as 8-inches (20 cm). Most of us will need something a little bigger. A 10-12 incher (25-30 cm) should do the trick until the comet swells into the 11-12 magnitude range. But you’ll need more than a hefty scope. Key to spotting ISON are good charts, a steady atmosphere for sharp images (shaky air blurs faint objects into invisibility) and catching the comet at the right time. I also encourage you to use averted vision, a great technique for spotting faint sky objects. Instead of staring directly at the comet, look off to the side of its position. That way you allow the comet’s feeble photons to flood your eye’s rod cells, those most sensitive to dim light.

This tighter view shows the comet in relation to the naked eye star Gamma Cancri and the lovely Beehive Cluster in Cancer the Crab. Stellarium
This tighter view shows the comet (on Sept. 3) in relation to the naked eye star Gamma Cancri and the pretty Beehive Cluster in Cancer the Crab. North is up, west to the right. Stellarium

While it now rises around 3-3:30 a.m. local time, you’ll get your best – or only – view once ISON has cleared the light-sucking thick air and haze so common near the horizon. The optimum viewing time occurs shortly before the start of morning twilight when the comet will be about 15 degrees high in the northeastern sky. At mid-northern latitudes,where twilight begins about 1.5 hours before sunrise, that’s around 5 a.m. Did I mention you’d lose a few hours sleep in your pursuit?

Comet ISON's position plotted for 5 a.m. Central Daylight Time tomorrow through the 10th. Stars are shown to 12th magnitude.  Click for larger version. Created with Chris Marriott's SkyMap Pro program
Comet ISON’s position plotted for 5 a.m. Central Daylight Time tomorrow through the 10th. Stars are shown to 12th magnitude. Click for larger version. Created with Chris Marriott’s SkyMap Pro program

Lucky for us comet hunters, ISON’s location is easy to find only a few degrees east of the 1st magnitude planet Mars and about 2 degrees north of the familiar Beehive Cluster or M44. The first map shows the general view to get you oriented. The second takes us in closer to show the comet’s relation to the Beehive Cluster, and the third provides a detailed telescopic view with stars plotted to about 12th magnitude. The comet positions on the detailed map are plotted for 5 a.m. CDT. Since ISON moves relatively slowly, those positions will be accurate for a time zone or two either way. If you live significantly farther east or west of the U.S. Central Time Zone, you can interpolate between the tick marks.

It’s good news for skywatchers from here on out as ISON continues to brighten and rise higher in the east with each passing night. A month from now, it should be visible in scopes as small as 6-inches (15 cm). Good luck in your comet quest!

Rumors of Comet ISON ‘Fizzling’ May be Greatly Exaggerated

A press release out yesterday about a recent paper on Comet ISON has caused a mild uproar across the astronomy-minded social media outlets and some websites. The article issued from the Physics & Astrophysics Computation Group (FACOM) at the University of Antioquia in Medellin, Colombia is titled “Comet Of The Century? Not Yet! Comet C/2012 S1 ISON Has Fizzled Completely And May Disintegrate At Or Before Reaching Perihelion.”

The article had professional astronomers and comet enthusiasts alike shaking their heads in disbelief.

For one, any current determination of ISON’s ultimate fate when it gets close to the Sun later this year is speculation at best, (as is the case with almost any other sun-grazing comet) and since no one on planet Earth has seen ISON since it entered the Sun’s glare in June, there is absolutely no way to determine the comet’s current state, either. The almost unanimous shout from the astronomy internets was “Please! We just have to wait and see what happens with ISON.”

But the press release also had this journalist (and others) wondering if Ferrin’s views were taken out of context for the sake of a dramatic press release.

For example, nowhere in his paper does Ferrin say that Comet ISON has “fizzled,” (nor is there a direct quote in the press release with that word) and he does make it clear in his paper that his information about the comet is preliminary. However, the press release seemingly infers there was new data and that the comet is nothing short of dead.

But in an email from Ferrin, in response to an inquiry from Universe Today, Ferrin stands by the press release, as well as his opinion that Comet ISON “does not have a bright future.”

“The term ‘fizzled completely’ is not a scientific term so it should not go into a scientific paper,” Ferrin said. “However it reflects reality with the information we have.”

His paper (a full 51-pages) was posted to arXiv on June 20, 2013, and has been submitted to the Monthly Notices of the Royal Astronomical Society, still undergoing peer review. The paper is based on data available up to the last good observing date in late-May, 2013, and Ferrin said in his email to Universe Today that up to that point “there is no evidence of brightening whatsoever. I doubt that anybody has seen that brightening.”

Ferrin, a well-known cometary scientist, concurred that the comet’s current state is unknown because it has entered the Sun’s glare but when last seen it had not brightened at all, adding in his email that “the fact that the comet was in a standstill situation makes it very improbable of becoming as bright as the Moon.”

As astronomer Karl Battams said, that last statement is hardly breaking news. Battams is an astrophysicist and computational scientist based at the Naval Research Laboratory in Washington DC, and he has operated the NASA-funded Sungrazing Comets Project since 2003. He’s also part of the Comet ISON Observing Campaign a massive, global observing campaign for ISON for both professional and amateur astronomers.

“Few serious astronomers and cometary scientists have ever felt ISON would be ‘brighter than the full Moon,’ Battams told Universe Today. “That’s entirely the media’s term, and we’ve been saying this for months, that none of us in the CIOC foresee ISON getting that bright, and never have done so. So we’re side-by-side with Ferrin in that respect.”

But Battams has some issues with both the paper and the press release.

“The paper is a mixture of reporting facts, and performing extrapolations and modeling based on certain theories and models, some of which are more developed than others,” Battams told Universe Today via email. “Ferrin’s analysis is based on data taken up until around the end of May, but the article misleads by implying that Ferrin has used recent data, which he hasn’t, as there is none. He has simply applied his own methods, model and analysis to the same data that we all have.”

Battams said he can’t comment on the quality of those models, but said Ferrin’s conclusions are broad enough that they don’t seem entirely out of line with what everyone else is saying about the comet – that there is a range of possible outcomes: Comet ISON might fizzle before it gets here or it might disintegrate before, or at perihelion, but it also might still brighten up.

“There’s really no new conclusion here — just a different methods that leads to the same conclusion,” Battams said.

In the paper, Ferrin reaches some of his conclusions comparing ISON to Comet Honig (2002 O4), the brightness of which he says “was in a standstill for 52 days after which it disintegrated.”

Battams said astronomers have to be cautious in comparing ISON to another comet – especially comparing it to Honig, which was not a sungrazer and shared little in common with ISON other than also being a comet.

“ISON is both a Sungrazer, and dynamically new from the Oort Cloud,” he said. “We have no modern record of such an object (see this article about ISON’s uniqueness) so we must exercise a little more caution than usual when comparing it to other comets. The last “major” sungrazer we had was Lovejoy in 2011, and for an object likely much smaller than ISON, it put on a pretty good show.”

Another astronomer with the CIOC, Matthew Knight from the Lowell Observatory also took issue with the comparison.

“Comparing ISON to 2002 O4 Honig ignores the fact that they were in very different places in the solar system,” Knight said via email, replying to an inquiry from Universe Today regarding Ferrin’s paper. “Honig began flattening out at 1.26 AU as it approached perihelion… ISON being flat at 4-5 AU is a completely different physical realm, since water and other volatiles are not expected to be very active yet.”

Knight also differed with Ferrin’s opinion that ISON’s peculiar non-brightening behavior when last seen “could possibly be explained if the comet were water deficient, or if a surface layer of rock or non-volatile silicate dust were quenching the sublimation to space.”

“This ignores the fact that water isn’t expected to be driving activity from January through June because ISON was still beyond the “frost line” (somewhere between 2.5 and 3 AU) beyond which water doesn’t sublimate efficiently because it is too cold,” Knight said. “It is only when a comet passes inside the frost line that water-driven activity is expected to ramp up…. I fully expect that once it passes inside the frost line, activity will pick up again. We should know as soon as it reemerges from behind the Sun in late August/early September.”

These images from NASA’s Spitzer Space Telescope of C/2012 S1 (Comet ISON) were taken on June 13, when ISON was 310 million miles (about 500 million kilometers) from the sun. Image credit: NASA/JPL-Caltech/JHUAPL/UCF
These images from NASA’s Spitzer Space Telescope of C/2012 S1 (Comet ISON) were taken on June 13, when ISON was 310 million miles (about 500 million kilometers) from the sun. Image credit: NASA/JPL-Caltech/JHUAPL/UCF

As to whether ISON has ‘fizzled’ both Battams and Knight noted that the recently released Spitzer observations from June 13 (and released on July 24 – well after Ferrin’s paper was published) showed the comet was ‘fizzy,’ not fizzled, as it was actively spewing out carbon dioxide and dust.

In the end, no matter what any current paper or press release says about Comet ISON, nothing will be known for sure until we see ISON again, and until it gets closer to the Sun. It will pass about 1.2 million km (724,000 miles) from the Sun at closest approach on November 28, 2013.

For now, everyone needs to wait and watch what happens and end the speculation.

However, as noted by Daniel Fischer on Twitter, the reaction caused by the press release related to Ferrin’s paper has been, unfortunately, “dramatic.”

Any hype either way — whether it is calling this the Comet of the Century or a comet that has fizzled — only does a disservice to astronomy, and gives the general public the wrong impression of both the comet and science’s ability to study and predict astronomical phenomenon.

Comet ISON is Spewing Out Carbon Dioxide and Dust

As part of the Comet ISON Observing Campaign, the Spitzer Space Telescope was used to “stare” at the comet for 24 hours on Jun 13, 2013. Images from Spitzer’s “ISON-a-thon” indicate that carbon dioxide and dust are spewing out of the comet at a fairly large rate.

“We estimate ISON is emitting about 2.2 million pounds (1 million kilograms) of what is most likely carbon dioxide gas and about 120 million pounds (54.4 million kilograms) of dust every day,” said Carey Lisse, leader of NASA’s Comet ISON Observation Campaign and a senior research scientist at the Johns Hopkins University Applied Physics Laboratory.

That amount of dust is about the mass of one aircraft carrier every two days or so, tweeted the Sungrazing Comets Twitter feed,, and the amount of carbon dioxide released per day would be enough for about 625 million cans of soda.

The images were taken by the Spitzer’s Infrared Array Camera showing the comet’s tail, which is about 186,400 miles (300,000 kilometers) long.

Comet ISON was about 312 million miles (502 million kilometers) from the Sun, 3.35 times farther than Earth, when the observations were made.

Comet ISON (C/2012 S1) is less than 3 miles (4.8 kilometers) in diameter (about the size of a small mountain) and weighs between 7 billion and 7 trillion pounds (3.2 billion and 3.2 trillion kilograms). However, its true size and density have not yet been accurately determined because of its distance from Earth. Like all comets, ISON is a dirty snowball made up of dust and frozen gases such as water, ammonia, methane and carbon dioxide. These are some of the fundamental building blocks, which scientists believe led to the formation of the planets 4.5 billion years ago.

“This observation gives us a good picture of part of the composition of ISON, and, by extension, of the proto-planetary disk from which the planets were formed,” said Lisse. “Much of the carbon in the comet appears to be locked up in carbon dioxide ice. We will know even more in late July and August, when the comet begins to warm up near the water-ice line outside of the orbit of Mars, and we can detect the most abundant frozen gas, which is water, as it boils away from the comet.”

The comet will pass within 724,000 miles (1.16 million kilometers) of the Sun on Nov. 28.

Astronomers are wondering if the comet will survive its close pass of the Sun, and also if it will live up to expectations of becoming bright enough to be seen in the daytime, as some have predicted.

Only time will tell … and we’ll be here to share the news.

Source: JPL

Curiosity Interview with Project Manager Jim Erickson-Part 2-Dealing with Dunes and Comet ISON on the Road to Mt. Sharp

Curiosity On the Road to Mount Sharp and treacherous Sand Dunes – Sol 338 – July 19
Curiosity captured this panoramic view of the path ahead to the base of Mount Sharp and potentially dangerous sand dunes after her most recent drive on July 19, 2013. She must safely cross over the dark dune field to climb and reach the lower sedimentary layers of Mount Sharp. Stowed robotic arm on rover deck seen at center.
See JPL traverse map below pinpointing the view from this location
Credit: NASA/JPL-Caltech/Ken Kremer-(kenkremer.com)/Marco Di Lorenzo[/caption]

NASA’s state-of-the-art Curiosity Mars rover is stepping up the driving pace and rolling relentlessly across alien Martian terrain towards the towering mystery mountain known as Mount Sharp that’s holds the keys to the Red Planets past evolution and whether its an abode for Life.

To uncover the latest scoop on the robots otherworldly adventures, Universe Today conducted an exclusive interview with the Curiosity Project Manager Jim Erickson, of NASA’s Jet Propulsion Laboratory (JPL).

In Part 2 of my conversation with Jim Erickson we’ll discuss more about the rover’s traverse across alien territory that’s simultaneously a science gold mine and a potential death trap, as well as Comet ISON and nighttime observations and science planning.

Read Part 1 – here.

“When Comet ISON is in the sky I’m sure we’ll do some observations of it depending on when its visible,” Erickson told me.

Today, July 20, is Sol 339 of the rovers mission to Mars. And also the 44th anniversary of the 1st human Moonwalks in 1969.

And Curiosity just drove another 34 meters yesterday, Sol 338 (July 19) – for a total distance exceeding 1.1 kilometers.

Curiosity's Traverse Map Through Sol 338 This map shows the route driven by NASA's Mars rover Curiosity through Sol 338 of the rover's mission on Mars (July 19, 2013).  Numbering of the dots along the line indicate the sol number of each drive. North is up. The scale bar is 200 meters (656 feet). From Sol 337 to Sol 338, Curiosity had driven a straight line distance of about 122.90 feet (32.59 meters). The base image from the map is from the High Resolution Imaging Science Experiment Camera (HiRISE) in NASA's Mars Reconnaissance Orbiter.  Image Credit: NASA/JPL-Caltech/Univ. of Arizona
Curiosity’s Traverse Map Through Sol 338
This map shows the route driven by NASA’s Mars rover Curiosity through Sol 338 of the rover’s mission on Mars (July 19, 2013). Numbering of the dots along the line indicate the sol number of each drive. North is up. The scale bar is 200 meters (656 feet). From Sol 337 to Sol 338, Curiosity had driven a straight line distance of about 122.90 feet (32.59 meters). The base image from the map is from the High Resolution Imaging Science Experiment Camera (HiRISE) in NASA’s Mars Reconnaissance Orbiter. Image Credit: NASA/JPL-Caltech/Univ. of Arizona

As for Martian sand dunes, they dunes offer both exciting opportunities and lurking dangers to the rovers well being.

Indeed fields of Martian sand dunes are potential death traps and the six wheeled rover has no choice but to traverse across an extensive dune field as she closes in on the base of Mount Sharp

Recall that NASA’s now long lived Opportunity rover nearly perished rather early in her mission at the ‘Purgatory’ dune field on Meridiani Planum.

Spirit died after more than six highly productive years on the Red Planet when she was unable to escape a hidden sand trap she had accidentally fallen wheels deep into as the vehicle was merrily roving beside an eroded volcano at Gusev Crater on the approach to the mysterious Von Braun mound.

So, dunes are serious business

Here is Part 2 of my interview with Jim Erickson.

Ken Kremer: Which direction is Curiosity headed? Will she be following the southwest route shown in the ellipse on the JPL map – see traverse map below – or reinvestigate any other spots nearer the landing site first?

Jim Erickson: We have a good general idea. We will be on a general heading of southwest, not west which would have taken us back near the landing site [at Bradbury Landing].

Curiosity Route Map From 'Glenelg' to Mount Sharp. This map shows where NASA's Mars rover Curiosity landed in August 2012 at "Bradbury Landing"; the area where the rover worked from November 2012 through May 2013 at and near the "John Klein" target rock in the "Glenelg" area; and the mission's next major destination, the entry point to the base of Mount Sharp.  Credit: NASA/JPL-Caltech/Univ. of Arizona
Curiosity Route Map From ‘Glenelg’ to Mount Sharp
This map shows where NASA’s Mars rover Curiosity landed in August 2012 at “Bradbury Landing”; the area where the rover worked from November 2012 through May 2013 at and near the “John Klein” target rock in the “Glenelg” area; and the mission’s next major destination, the entry point to the base of Mount Sharp. Credit: NASA/JPL-Caltech/Univ. of Arizona

Ken: So the rover will not pass by the Hottah outcrop of concretions formed in water and investigated early in the mission?

Jim Erickson: No. The intent for the ellipse [shown on the map] is that we will be traveling in it to get to an area where the sand dunes look better for crossing [to the base of Mount Sharp]. When we get there we will know reality. And we will pick a safe spot to cross.

The dunes can be both an issue or in some cases easy sailing.

My experience on MER [Spirit & Opportunity] was that when you are going with the dunes, down a trough, they tend to be well packed and that was great driving.

But if you need to make a right turn, that can be a challenge for a couple of reasons. It is harder to see what is inside the next trough. And you have to drive to the top of the dune. So your driving is limited until you can see what’s inside the next dune.

Level ground is more straightforward. You know exactly what to look for if the terrain doesn’t change the next day. So you can do the same thing you did last night based on the new set of images.

If the terrain is changing then it gets more complicated.

Ken: Will you be straddling the dunes or driving alongside some safe distance away?

Jim Erickson: We have been going through various options of different planned routes. At some point we have to go with the dune directions.

So we’ll be traveling down some troughs later on. We will definitely have to pick our way through them.

Part of it is gaining experience in this new area of Mars with how the sand dunes and troughs themselves actually are.

So we’ll have to wait and see. We know we’ll have to deal with the dunes. Depending on how these dunes act we may have to do different things compared to MER.

Ken: What’s the health status of Curiosity?

Jim Erickson: We’re doing great. There are always active things we are looking at.

We had the anomaly before conjunction and have put in place a number of software mitigations and reconfigured the A side memory so that we can work around the hardware problem that happened. If we have another problem, both the A and B side memory can handle it gracefully, unlike the last time.

Ken: Describe the rover’s power situation? And the ability to do nighttime observations like the recent imagery of Phobos rising?

Read earlier Phobos story – here

Jim Erickson: Yes. We have plenty of power.

And certainly will be able to do nighttime observations.

Ken: What’s the plan for observations of Comet ISON?

Jim Erickson: When we get to the point when Comet ISON is in the sky I’m sure we’ll do some observations of it, depending on the time period when its visible.

Note: NASA’s Curiosity and Opportunity rovers will have a view of ISON in October with Oct. 1, 2013, being the comet’s closest approach to Mars.

NASA’s Directory of Planetary Science Jim Green told me previously that NASA is very interested in using its orbiting and surface assets at Mars to study Comet ISON. It’s a once in a lifetime opportunity.

Early October 2013 will be the prime viewing time for ISON from the vicinity of the Red Planet.

Let’s hope that NASA’s quartet of spacecraft and ESA’s lone orbiter capture some breathtaking imagery and science observations.

Ken: About the recent Phobos nighttime images, a Universe Today reader asked whether the other points of light beside Phobos were stars or hot pixels?

Jim Erickson: The specks are hot pixels [not stars], intensified by the long exposure times for the image.


Video Caption: ‘Phobos Rising’ – This movie clip shows Phobos, the larger of the two moons of Mars, passing overhead, as observed by Curiosity in a series of images centered straight overhead starting shortly after sunset on June 28, 2013. Phobos first appears near the lower center of the view and moves toward the top of the view. The apparent ring is an imaging artifact. The other bright spots are hot pixels – not stars. Credit: NASA/JPL-Caltech

Ken: How about the prospects for science along the way to the mountain?

Jim Erickson: We expect to do science along the way to Mount Sharp, for example in terms of atmospheric measurements.

We will stop at some preplanned sites. Exactly which ones is still being debated by the scientists.

And we’ll do the right thing – If we see something spectacular along the way. Just because we may not have identified it previously, that doesn’t mean we won’t stop and examine it.

Things are going very well, says Erickson.

Erickson has worked in key positions on many NASA planetary science missions dating back to Viking in the 1970’s. These include the Galileo mission to Jupiter, both MER rovers Spirit & Opportunity, as well as a stint with the Mars Reconnaissance Orbiter (MRO).

I’ll have more upcoming from Jim about Curiosity’s Martian drilling activities.

As of today (July 20) Curiosity has driven nine times since leaving the Glenelg/Yellowknife Bay area on July 4 (Sol 324), totaling nearly 300 meters.

Stay tuned for more from Mars.

Ken Kremer

This photomosic shows NASA’s Curiosity departing at last for Mount Sharp- her main science destination. Note the wheel tracks on the Red Planet’s surface. The navcam camera images were taken on July 4, 2013 (Sol 324). Credit: NASA/JPL-Caltech/Ken Kremer (kenkremer.com)/Marco Di Lorenzo
This photomosic shows NASA’s Curiosity departing at last for Mount Sharp- her main science destination. Note the wheel tracks on the Red Planet’s surface. The navcam camera images were taken on July 4, 2013 (Sol 324). Credit: NASA/JPL-Caltech/Ken Kremer (kenkremer.com)/Marco Di Lorenzo
Mount Sharp inside Gale Crater - is the primary destination of NASA’s Curiosity rover mission to Mars.  Curiosity landed on the right side of the mountain as shown here, near the dune field colored dark blue.  Mount Sharp dominates Gale Crater. It is 3.4 mile (5.5 km) high.  Gale Crater is 154 km wide. This image was taken by the High Resolution Stereo Camera (HRSC) of ESA’s Mars Express orbiter.  Credit: ESA/DLR/FU Berlin (G. Neukum)
Mount Sharp inside Gale Crater – is the primary destination of NASA’s Curiosity rover mission to Mars. Curiosity landed on the right side of the mountain as shown here, near the dune field colored dark blue. Mount Sharp dominates Gale Crater. It is 3.4 mile (5.5 km) high. Gale Crater is 154 km wide. This image was taken by the High Resolution Stereo Camera (HRSC) of ESA’s Mars Express orbiter. Credit: ESA/DLR/FU Berlin (G. Neukum)

Stars, Galaxies, and Comet ISON Grace a New Image from Hubble

This image of the steadily-approaching Comet ISON, made from observations with the Hubble Space Telescope on April 30, show not only the comet itself but also a rich background of stars located within our own galaxy and even the distant spirals of entire galaxies much, much farther away — as Josh Sokol describes it on HubbleSite.org’s ISONblog it’s like the astronomy stickers you’d get for your kid’s bedroom, except you’d never get to see such a scene in real life “unless, of course, you had Hubble.”

Comet C/2012 S1 (ISON) is currently on its way into the inner Solar System on course for a close encounter with the Sun, zooming along at 77,250 km/h (48,000 miles per hour). It will make its closest pass by the Sun on November 28 (coming within just .012 AU) and will hopefully put on a pretty spectacular show in the night sky —  especially if it survives the trip.

The track of Comet ISON through the constellations Gemini, Cancer and Leo prior to perihelion. (Credit: NASA/GSFC/Axel Mellinger).
Comet ISON’s projected path through the night sky prior to perihelion. (Credit: NASA/GSFC/Axel Mellinger)

Watch: Comet ISON Timelapse Hubble Movie

The image above was created from multiple Hubble observations earlier this year, some geared toward capturing ISON and others calibrated more for distant, dimmer objects like galaxies and far-flung stars. By combining the results we get a view of a comet speeding through space with an almost too-perfect hyperrealism, courtesy of NASA’s hardest-working space telescope.

“The result is part science, part art. It’s a simulation of what our eyes, with their ability to dynamically adjust to brighter and fainter objects, would see if we could look up at the heavens with the resolution of Hubble. The result is a hodepodge of almost all the meat-and-potatoes subjects of astronomy – no glow-in-the-dark stickers required.”

– Josh Sokol, HubbleSite ISONblog

Learn about other ways NASA will be observing Comet ISON here.

Source: HubbleSite.org