While the Camelopardalid shower only produced a few meteors, the lack of flashy disintegrations showed astronomers something new, a new study reveals: the dust from its parent comet (Comet 209P/Linear) was much more fragile than the usual. The reasons are still being investigated, but one theory is that after a century in space, there wasn’t much left to run into.
“Some mechanism was at work that efficiently fragmented the larger meteoroids,” stated Peter Jenniskens, a meteor astronomer with the SETI Institute who, along with colleague Esko Lyytinen, first predicted the existence of the shower a decade ago.
“Our best meteor was no more luminous than the star Vega,” added Jenniskens, “but it gave us a clue as to why there were few bright ones: It was so fragile that the meteoroid suddenly dispersed into a cloud of dust at the end of its trajectory.”
This ‘weak” shower stands in contrast to two meteor showers that took place out of interactions with comet 21P/Giacobinni-Zinner. This produced meteor “storms” in 1933 and 1946 during the Draconids. That comet was more active and the dust grains that left it likely had a lot of ice in them. Comet 209P/Linear did not have that type of ejection, nor was it very active.
If the hoped-for meteor blast materializes this Friday night / Saturday morning (May 23-24) Earth won’t be the only world getting peppered with debris strewn by comet 209P/LINEAR. The moon will zoom through the comet’s dusty filaments in tandem with us.
Bill Cooke, lead for NASA’s Meteoroid Environment Office, alerts skywatchers to the possibility of lunar meteorite impacts starting around 9:30 p.m. CDT Friday night through 6 a.m. CDT (2:30-11 UTC) Saturday morning with a peak around 1-3 a.m. CDT (6-8 UTC).
While western hemisphere observers will be in the best location, these times indicate that European and African skywatchers might also get a taste of the action around the start of the lunar shower. And while South America is too far south for viewing the Earth-directed Camelopardalids, the moon will be in a good position to have a go at lunar meteor hunting. Find your moonrise time HERE.
The thick crescent moon will be well-placed around peak viewing time for East Coast skywatchers, shining above Venus in the eastern sky near the start of morning twilight. For the Midwest, the moon will just be rising at that hour, while skywatchers living in the western half of the country will have to wait until after maximum for a look:
“Anyone in the U.S. should monitor the moon until dawn,” said Cooke, who estimates that impacts might shine briefly at magnitude +8-9.
“The models indicate the Camelopardalids have some big particles but move slowly around 16 ‘clicks’ a second (16 km/sec or 10 miles per second). It all depends on kinetic energy”, he added. Kinetic energy is the energy an object possesses due to its motion. Even small objects can pack a wallop if they’re moving swiftly.
Bright lunar meteorite impact recorded on video on September 11, 2013. The estimated 900-lb. space rock flared to 4th magnitude.
Lunar crescents are ideal for meteor impact monitoring because much of the moon is in shadow, illuminated only by the dim glow of earthlight. Any meteor strikes stand out as tiny flashes against the darkened moonscape. For casual watching of lunar meteor impacts, you’ll need a 4-inch or larger telescope magnifying from 40x up to around 100x. Higher magnification is unnecessary as it restricts the field of view.
I can’t say how easy it will be to catch one, but it will require patience and a sort of casual vigilance. In other words, don’t look too hard. Try to relax your eyes while taking in the view. That’s why the favored method for capturing lunar impacts is a video camera hooked up to a telescope set to automatically track the moon. That way you can examine your results later in the light of day. Seeing a meteor hit live would truly be the experience of a lifetime. Here are some additional helpful tips.
On average, about 73,000 lbs. (33 metric tons) of meteoroid material strike Earth’s atmosphere every day with only tiny fraction of it falling to the ground as meteorites. But the moon has virtually no atmosphere. With nothing in the way, even small pebbles strike its surface with great energy. It’s estimated that a 10-lb. (5 kg) meteoroid can excavate a crater 30 feet (9 meters) across and hurl 165,000 lbs. of lunar soil across the surface.
A meteoroid that size on an Earth-bound trajectory would not only be slowed down by the atmosphere but the pressure and heat it experienced during the plunge would ablate it into very small, safe pieces.
NASA astronomers are just as excited as you and I are about the potential new meteor shower. If you plan to take pictures or video of meteors streaking through Earth’s skies or get lucky enough to see one striking the moon, please send your observations / photos / videos to Brooke Boen ([email protected])at NASA’s Marshall Space Flight Center. Scientists there will use the data to better understand and characterize this newly born meteor blast.
On the night of May 23-24, Bill Cooke will host a live web chat from 11 p.m. to 3 a.m. EDT with a view of the skies over Huntsville, Alabama. Check it out.
As we anxiously await the arrival of a potentially rich new meteor shower this weekend, its parent comet, 209P/LINEAR, draws ever closer and brighter. Today it shines feebly at around magnitude +13.7 yet possesses a classic form with bright head and tail. It’s rapidly approaching Earth, picking up speed every night and hopefully will be bright enough to see in your telescope very soon.
The comet was discovered in Feb. 2004 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) automated sky survey. Given its stellar appearance at the time of discovery it was first thought to be an asteroid, but photos taken the following month photos by Rob McNaught (Siding Spring Observatory, Australia) revealed a narrow tail. Unlike long period comets Hale-Bopp and the late Comet ISON that swing around the sun once every few thousand years or few million years, this one’s a frequent visitor, dropping by every 5.09 years.
209P/LINEAR belongs to the Jupiter family of comets, a group of comets with periods of less than 20 years whose orbits are controlled by Jupiter. When closest at perihelion, 209P/LINEAR coasts some 90 million miles from the sun; the far end of its orbit crosses that of Jupiter. Comets that ply the gravitational domain of the solar system’s largest planet occasionally get their orbits realigned. In 2012, during a relatively close pass of that planet, Jupiter perturbed 209P’s orbit, bringing the comet and its debris trails to within 280,000 miles (450,000 km) of Earth’s orbit, close enough to spark the meteor shower predicted for this Friday night/Saturday morning May 23-24.
This time around the sun, the comet itself will fly just 5.15 million miles (21 times the distance to the moon) from Earth around 3 a.m. CDT (8 hours UT) May 29 a little more than 3 weeks after perihelion, making it the 9th closest comet encounter ever observed. Given , you’d think 209P would become a bright object, perhaps even visible with the naked eye, but predictions call for it to reach about magnitude +11 at best. That means you’ll need an 8-inch telescope and dark sky to see it well. Either the comet’s very small or producing dust at a declining rate or both. Research published by Quanzhi Ye and Paul A. Wiegert describes the comet’s current dust production as low, a sign that 209P could be transitioning to a dormant comet or asteroid.
Fortunately, the moon’s out of the way this week and next when 209P/LINEAR is closest and brightest. Since we enjoy comets in part because of their unpredictability, maybe a few surprises will be in the offing including a brighter than expected appearance. The maps will help you track down 209P during the best part of its apparition. I deliberately chose ‘black stars on a white background’ for clarity in use at the telescope. It also saves on printer ink!
We’re grateful for the dust 209P/LINEAR carelessly lost during its many passes in the 19th and early 20th centuries. Earth is expected to pass through multiple filaments of debris overnight Friday May 23-24 with the peak of at least 100 meteors per hour – about as good as a typical Perseid or Geminid shower – occurring around 2 a.m. CDT (7 hours UT).
If it’s cloudy or you’re not in the sweet zone for viewing either the comet or the potential shower, astrophysicist Gianluca Masi will offer a live feed of the comet at the Virtual Telescope Project website scheduled to begin at 3 p.m. CDT (8 p.m. Greenwich Time) May 22. A second meteor shower live feed will start at 12:30 a.m. CDT (5:30 a.m. Greenwich Time) Friday night/Saturday morning May 23-24.
SLOOH will also cover 209P/LINEAR live on the Web with telescopes on the Canary Islands starting at 5 p.m. CDT (6 p.m. EDT, 4 p.m. MDT and 3 p.m. PDT) May 23. Live meteor shower coverage featuring astronomer Bob Berman of Astronomy Magazine begins at 10 p.m. CDT. Viewers can ask questions by using hashtag #slooh.
On Friday night/early Saturday May 23-24 skywatchers across the U.S. and southern Canada may witness the birth of a brand new meteor shower. If predictions hold true, Earth will pass through multiple tendrils of dust and pebbly bits left behind by comet 209P/LINEAR, firing up a celestial display on par with the strongest showers of the year. Or better.
Earlier predictions called for a zenithal hourly rate or ZHR of 1,000 per hour, pushing this shower into the ‘storm’ category. ZHR is an idealized number based on the shower radiant located at the zenith under ideal skies. The actual number is lower depending on how far the radiant is removed from the zenith and how much light pollution or moonlight is present. Meteor expert Peter Jenniskens of the SETI Instituteand Finland’s Esko Lyytinen first saw the possibility of a comet-spawned meteor storm and presented their results in Jenniskens’ 2006 book Meteor Showers and Their Parent Comets.
Quanzhi Ye and Paul Wiegert (University of Western Ontario) predict a weaker shower because of a decline in the comet’s dust production rate based on observations made during its last return in 2009. They estimate a rate of ~200 per hour.
On the bright side, their simulations show that the comet sheds larger particles than usual, which could mean a shower rich in fireballs. Other researchers predict rates between 200 and 40o per hour. At the very least, the Camelopardalids – the constellation from which the meteors will appear to originate – promise to rival the Perseids and Geminids, the year’s richest showers. Motivation for setting the alarm clock if there ever was.
Comet 209P/LINEAR, discovered in Feb. 2004 by the automated Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) sky survey, orbits the sun every 5.04 years with an aphelion (most distant point from the sun) near Jupiter. In 2012, during a relatively close pass of that planet, Jupiter perturbed its orbit, bringing it to within 280,000 miles (450,000 km) of Earth’s orbit.
That set up a remarkably close encounter with our planet on May 29 when 209P will cruise just 5 million miles (8 million km) from Earth to become the 9th closest comet ever observed. Multiple debris trails shed by the comet as long ago as the 18th century will intersect our planet’s path 5 days earlier, providing the material for the upcoming meteor shower/storm.
Shining meekly around magnitude +17 at the moment, 209P/LINEAR could brighten to magnitude +11 as it speeds from the Big Dipper south to Hydra during the latter half of May. Closer to the BIG night, we’ll provide helpful maps for you to track it down in your telescope. Cool to think that both the shower and its parent comet will be on display at the same time.
The shower’s expected to last only a few hours from about 12:40-3:50 a.m. CDT with the best viewing locations in the U.S. and southern half of Canada. This is where the radiant will be up in a dark sky at peak activity. A thick crescent moon rises around 3-3:30 a.m. but shouldn’t pose a glare problem.
Meteors from 209P/LINEAR are expected to be bright and slow with speeds around 40,000 mph compared to an average of 130,000 mph for the Perseids. Most shower meteoroids are minute specks of rock, but the Camelopardalids contain a significant number of particles larger than 1mm – big enough to spark fireballs.
The farther north you live in the shaded area on the map, the higher the radiant stands in the northern sky and the more meteors you’re likely to see. Skywatchers living in the Deep South will see fewer shooting stars, but a greater proportion will be earthgrazers, those special meteors that skim the upper atmosphere and flare for an unusually long time before fading out.
To see the shower at its best, find a dark place with an open view to the north. Plan your viewing between 12:30 and 4 a.m. CDT (May 24), keeping the 2 a.m. forecast peak in mind. Maximum activity occurs around 3 a.m. Eastern, 1 a.m. Mountain and midnight Pacific time.
No one’s really certain how many meteors will show, but I encourage you to make the effort to see what could be a spectacular show.
It’s always one of the most reliable of the annual meteor showers, however, this year the Geminids had to compete with a bright waxing gibbous Moon, which reached Full Moon status today, just 3 days after the shower’s peak over the weekend. But as always, our astrophotographer friends were out in force to try and capture a meteor or two with their cameras. Take a look at our great gallery of shots from around the world, and thanks to everyone who submitted their images to Universe Today’s Flickr page!
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Personally, I’ve never seen anything like this, and photographer and digital artist Michael K. Chung said he couldn’t believe what he saw when he was processing images he took for a timelapse of the Perseid meteor shower. It appears he captured a meteor explosion and the resulting expansion of a shock wave or debris ring.
“It was taken early in the morning on August 12, 2013 from my backyard in Victorville, CA,” Michael told Universe Today via email. “The fade to white is NOT an edit- it is overexposure due to the sun coming up. From what I can tell, the timelapse sequence of the explosion and expanding debris span an actual time of approximately 20 minutes.”
Michael said because he shoots at much higher resolution than 720p, he’s able to provide two different sequences in this video: one is with the full frame of each capture scaled/reduced and then cropped down to 1280×720, and the other is with the full frame kept at resolution with just the region around the explosion cropped to 1280×720. “I included each sequence twice – once at 24 frames per second and the other at around 12 fps.”
Since I’ve never seen anything like this, I decided to have one of our observing experts provide his opinion. UT writer David Dickinson said this is definitely legitimate.
“What cinches it for me is that the meteor was moving in the right direction for a Perseid,” Dave told me. “I see Perseus rising to the right, the plane of the Milky Way and Andromeda just above center.”
Dave said he has seen several meteors that leave lingering smoke trains. “I usually carry binoculars to examine these,” he said, “and saw several examples of this during the 1998 Leonid meteor storm from the desert in Kuwait, one of the most awesome things I’ve seen. Ever.”
We heard from a few more people who also witnessed and captured similar Perseids with persistent trains.
Steve Knight from the UK also captured some explody-Perseids this year. Take a look at his video below, and at :15 and :19 there are fireballs followed by expanding cloud of debris — to see it better expand the video and look at the top right part of the screen. Andromeda Galaxy (M31) is visible drifting in from the left.
And Steve also provided animated gifs of the explosions:
Also, Randy Halverson from Dakotalapse, whose work we feature frequently on UT sent a couple of images of persistent trains from meteors, like this one:
…and this one of the cloud of debris left from a persistent train:
Watch his timelapse here, with the explosion taking place at about :53 into the film:
Get set for the meteoritic grand finale of summer.
Northern hemisphere summer that is. As we head into August, our gaze turns towards that “Old Faithful” of meteor showers, the Perseids. Though summer is mostly behind us now, “meteor shower season” is about to get underway in earnest.
Pronounced “Pur-SEE-ids,” this shower falls around the second week of August, just before school goes back in for most folks. This time of year also finds many the residents of the northern hemisphere out camping and away from light-polluted suburban skies.
This year also offers a special treat, as the Moon will be safely out of the sky during key observation times. The Moon reaches New phase on August 6th at 5:51 PM EDT/ 9:51 Universal Time (UT) and will be a 32% illuminated waxing crescent around the anticipated peak for the Perseid meteors on August 12th. And speaking of which, the Perseids are infamous for presenting a double-fisted twin peak in activity. This year, the first climax for the shower is predicted for around 13:00 UT on August 12th, favoring Hawaii and the North American west coast, and the second peak is set to arrive 13 hours later at 02:00 UT, favoring Europe & Africa.
Nodal crossing for the Perseid stream and Earth’s orbit sits right around 18:00 to 21:00 UT on August 12th for 2013. The shower derives its name from the constellation Perseus, and has a radiant located near Gamma Persei at right ascension 3 hours 4 minutes and a declination of +58 degrees. Atmospheric velocities for the Perseids are on the high end as meteor showers go, at 59km/sec.
Of course, like with any meteor shower, it’s worth starting to watch a few days prior to the peak date. Although meteor streams like the Perseids have been modeled and mapped over the years, there are still lots of surprises out there. Plus, starting an early vigil is insurance that you at least catch some action in the event that you’re clouded out on game day! Like we mentioned in last week’s post on the Delta Aquarids, the Perseids are already active, spanning a season from July 17th to August 24th.
The Zenithal Hourly Rate for the Perseids is generally between 60-100 meteors. The ZHR is the number of meteors you could expect to see during optimal conditions under dark skies with the radiant directly overhead. Rates were enhanced back in the 1990’s, and 2004 saw a ZHR of 200.
The source of the Perseids is comet 109P/Swift-Tuttle. Discovered on July 16th-19th, 1862 by astronomers Lewis Swift & Horace Tuttle, Swift-Tuttle is on a 133.3 year orbit and last passed through the inner solar system in late 1992. This comet will once again grace our skies in early 2126 AD.
The Perseids are also sometimes referred to as the “tears of St Lawrence,” after the Catholic saint who was martyred on August 10th, 258 AD. The Perseids have been noted by Chinese astronomers as far back as 36 AD, when it was recorded that “more than 100 meteors flew thither in the morning.” The annual nature of the shower was first described by Belgian astronomer Adolphe Quételet in 1835.
Enhanced rates for the Perseids marked the return of comet Swift-Tuttle in the 1990s. Recent years have seen rates as reported by the International Meteor Organization at a ZHR=175(2009), 91(2010), 58(2011), & a resurgence of a ZHR=122 last year.
Just what will 2013 bring? There’s one truism in meteor observing—you definitely won’t see anything if you do not get out and observe. Meteor shower observing requires no equipment, just clear skies and patience. Watch in the early hours before dawn, when the rates are highest. Meteors can occasionally be seen before midnight, but are marked by lower rates and slow, stately trains across the sky. Some suggest that best viewing is at a 45 degree angle away from the radiant, but we maintain that meteors can appear anywhere in the sky. Pair up with a friend or two and watch in opposite directions to increase your meteor-spotting chances.
We also like to keep a set of binoculars handy to examine those smoke trains left by bright fireballs that may persist seconds after streaking across the sky.
And speaking of which, there has also been some spirited discussion over the past week as to whether or not the Perseids produce more fireballs than any other shower. I certainly remember seeing several memorable fireballs from this shower over the years, although the Geminids, Leonids and Taurids can be just spectacular on active years. The stated r value of the Perseids is one of the lowest at 2.2, suggesting a statistically high percentage of fireballs.
And in the realm of the strange and the curious, here are just a few phenomena to watch/listen for on your Perseid vigil;
– Can you “hear” meteors? Science says that sounds shouldn’t carry through the tenuous atmosphere above 50 kilometres up, and yet reports of audible meteors as a hiss or crackle persist. Is this an eye-brain illusion? Researchers in 1988 actually studied this phenomenon, which is also sometimes reported during displays of aurora. If there’s anything to it, the culprit may be the localized generation of localized electrophonic noises generated by Extra/Very Low Frequency electromagnetic radiation.
– Can meteor streaks appear colored? Green is often the top reported hue.
– Can meteors appear to “corkscrew” during their trajectory, or is this an illusion?
Wide-field photography is definitely a viable option during meteor showers. Just remember to bring extra charged batteries, as long exposure times will drain modern DSLRs in a hurry!
And did you know: you can even “listen” to meteor pings on an FM radio or portable TV? This is a great “rain check” option!
And there’s still real science to be done in the world of meteor shower studies. The International Meteor Organization welcomes counts from volunteers… and be sure to Tweet those Perseid sightings to #Meteorwatch.
Also be sure to check out the UK Meteor Observation Network, which has just launched their live site with streaming images of meteors as they are recorded.
Good luck, clear skies, and let the late 2013 meteor shower season begin!
-And be sure to post those Perseid pics to the Flickr forum on Universe Today… we’ll be doing photo essay roundups from observers around the world!
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