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[Click on image for larger version]
Jeremie Vaubaillon, Caltech, created this composite image of the 2008 Quadrantid shower combining short exposures of meteors and aurora seen during the returning leg of the Quadrantid MAC mission.
News
2008 Jan 31 - Participants Juergen Wolf and
Karsten Schindler of the Deutsche SOFIA Institut, who work at NASA Ames Research Center, released another scenic Quadrantid shower image. Their other images (see below) were also processed to remove dark current and image imperfections [click on images]. Report [pdf]. Univ. Stuttgart news.
2008 Jan 07 - Astronomy Picture of the Day; NASA Image of the Day
2008 Jan 05 - NOAA announces that the new solar cycle, cycle 24, has started. The Aurora observed during the Quadrantid MAC was likely part of the very first sequence of Aurora in the new season.
Very preliminary results (Jan 5, 2008) from Quadrantid counts by the Flux Measurement Team during the mission, analysed by Peter Jenniskens. Results are compared to counts from visual observers on the ground, collected so far by the International Meteor Organization.
2008 Jan 05 - First impressions can be deceiving: the peak appears to have been at the end of the night. The graph shows my first quick analysis of the counts that were made by the Flux Measurement Team (Dave Holman, Mike Koop, Robin Gray, Mike Wilson, and David Nugent). A total of 846 Quadrantids were counted in near-real time during the observations, all coming in from a 15-30 degree high radiant elevation. The peak of the shower appears to have been around the same time as in 1997 (shown as a dashed line). These are preliminary results (observers each put in nearly 7 hours of counting!) that await a re-examination of the video tapes. If confirmed in later analysis, this would imply that the node of the stream is more stable than our model predicted and the shower peaked over the eastern USA and Canada. The shower does appear to be variable in intensity. I hope we get a chance to do this again in the future. Keep tuned. - Peter Jenniskens
Group photo. From left to right: Danielle Townsend, Ron Dantowitz, Jim Albers (standing), Robin Gray, Mike Koop, Jeremie Vaubaillon, Mike Wilson, Jason Hatton, Peter Jenniskens, David Nugent, Juergen Wolf, Karsten Schindler, and David Holman. Not included: Rick Rairden. Other group photo.
Live Updates
2008, Jan. 03 (Jan 04 UT)
12:20 p.m. PST (= 8:20 UT)
The team is now only an hour away from home - but not yet bed. They have just passed over Spokane, Washington. The plane is expected to land at 1:45 a.m. PST, but the team plans to unpack their equipment, head over to the SETI Institute, and upload some of their images immediately to this website.
The team has gained more spectra and Peter is pleased with the results - there are several lines visible. The shower itself is ongoing, though the rate is going down. Watching the meteors from the plane gives a different angle than watching from the ground - they seem to graze the atmosphere and move more slowly, allowing more time to appreciate their beauty as well as observe them scientifically.
Spectrum of a bright Quadrantid captured by Danielle Townsend of Southfield School. The main emission lines are identified. This meteor had an end flare.
Juergen Wolf and Karsten Schindler of the Deutsche SOFIA Institut recorded this Quadrantid with an interesting light curve, while testing a camera for future use on the SOFIA aircraft.
Peter stated that he hoped that it was still raining in San Jose - if it wasn't, he's afraid that he'll become one of the ground observers and not get to bed at all! He was assured that the cloud cover was fairly comprehensive in the Bay Area.
This is the last update from me (Barbara Vance of the SETI Institute), but if you can stay tuned a few more hours, you should be rewarded with images of the meteors and the aurora. I'll be looking forward to them!
And remember - if you have stories or images of the Quadrantids, please report them to Peter at:
pjenniskens [at] seti.org
Happy New Year, and thanks for joining us in this mission!
11:13 p.m. PST (= 7:13 UT)
The plane has just passed over Edmonton, Canada - the glow from the city was visible. The sky is beautiful, and Sirius is shining brightly on them.
The team is 2 1/2 hours or so from home. They are still taking videos, and the rate is continuing to decrease. So far, no further great spectra, but they are still hoping to get more. Peter reports that the visuals from this mission will be stunning.
The team is pretty tired, and currently working on trying to figure out where the coffee is kept, so they can make some. The pilot is volunteering to assist.
Juergen Wolf and Karsten Schindler captured this Quadrantid meteor amidst aurora.
9:08 p.m. PST (= 5:08 UT)
The team is on their way home, about 4 hours out, but that isn't stopping the observations. They have their first confirmed spectra, and there will be more. The rate is indeed going down, though still fluctuating - at present it is about 40/hour.
The actual flight path took us above the Arctic circle.
Making me jealous to be on the ground in Mountain View, Peter says that the aurora is "spectacular" - and they have some great video and stills of the aurora and meteors, so look forward to some stunning graphics soon.
The ESA SPOSH camera recorded this stunning view of the Aurora near the turnaround point above the Arctic circle. Photo: Jason Hatton, ESA/ESTEC
Jeremie Vaubaillon recorded this sequence of images of the Aurora. This display may have been part of the very first sequence of Aurora in the new solar cycle, cycle 24. NOAA announced the start of the new solar cycle on January 5. See also: Aurora animation (5.18 Mbyte) from images taken by Jason Hatton using a Nikon D50 camera with allsky 10.5 mm f2.8 lens.
Based on preliminary results, he now thinks that Jeremy's model of the stream is correct - it was created circa 1490 AD, three years before Columbus' journey to the New World.
8:08 p.m. PST (= 4:08 UT)
The team is now "way up into the Northern Territories" according to the pilot, above the Arctic Circle. Team members are taking their first break, crowding into the cockpit to view the amazing aurora, best seen off the right side of the plane.
The team has witnessed a flurry of meteors in the last few minutes - the rate is still high, and the numbers still fluctuating up and down. They are gathering "lots of data" and are very pleased with the observations so far. The ZHR is estimated to have started around 70, peaked at 110, and is now about 90, but it is difficult to determine this with the many different observers and cameras aboard. Stay tuned for more on this. The Sporadic Rate has been about constant at 10.
The plane will be making its turn in about 15 minutes to start heading back south, but of course observation will be continuing.
The team is very excited and pleased with the mission - and the confirmation of many of the predictions and models.
The next update should be around 9:00 p.m. PST.
Juergen Wolf and Karsten Schindler captured this Quadrantid above
the cloud deck.
7:20 p.m. PST (= 3:20 UT)
The plane is now over the Northern Territories, heading for the Aurora Borealis, which can be seen in the distance already. The team should be flying straight through it! There is a clear horizon and air glow.
It is believed that the peak was reached at 2:12 UT (6:12 PST), which explains why there was a delay in reporting! This preliminary report needs a few more hours of observing before it can be confirmed. The peak recorded 110/hour, with a mean so far for the flight of 100/hour. The team is now seeing about 90/hour, but this may yet ramp up over the next few hours. Jeremy has already obtained some beautiful digital photographs of some nice, long, slow meteors - Peter predicts another Astronomy Photo of the Day! There is no spectra to report as yet, but this is hard to determine in flight. Peter will inform us when this is available.
Jeremie Vaubaillon captured this Quadrantid meteor just above the
wing of the aircraft.
Juergen Wolf and Karsten Schindler captured this Quadrantid amidst airglow low above the horizon.
6:00 p.m. PST (= 2:00 UT)
The team has been observing meteors for about half an hour now - this seems to indicate that the peak will be early, matching the model predictions. The team is counting about 75/hour, higher than the Perseids. The meteors are coming in at a shallow angle, giving the viewers a sight of long tails through Orion and Gemini.
5:32 p.m. PST (= 1:32 UT)
It is now dark enough for the team to start filming the sky - the instruments are in the final setting-up stage. The plane left San Jose on time at 3:47, and their flight is also on schedule. They should be starting to view in about 15 minutes.
5:10 p.m. PST (= 1:10 UT)
Hello everyone! We have established communications with the aircraft, and will be posting live updates every half hour.
Take off from San Jose Minetta International Airport as photographed by Brian Murahashi.
The plane left San Jose, California, amid heavy rain, but soon climbed above it. The plane is now over southern Oregon, and the crew and scientists are enjoying a beautiful sunset in blue skies. The team is setting up their instruments and lights down is about to occur.
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UTC: Jan 04 1:30 a.m. - Jan 04 9:30 a.m.
EST: Jan 03 8:30 p.m. - Jan 04 4:30 a.m.
PST: Jan 03 5:30 p.m. - Jan 04 1:30 a.m.
Visual observations from ground-based observers are being collected by the International Meteor Organization, where they are automatically posted as a graph.
News
2008 Jan 01 - Happy New Year! For Nature's own firework display: What will you see early morning January 4?
2008 Jan 02 - Aircraft prepared, instruments set up and tested. Some 25 cameras of different kind are being deployed.
2008 Jan 01 - Preparations at SETI Institute. Instruments are being assembled.
2007 Dec 31 - While out walking the dog last night I also scouted for a good
location for observing the coming Quandrantids. I guess I was looking
at the right place at the right time. As I was orienting myself to
the radiant position with respect to one possible observing location,
A beautiful, golden mag 1 Quandrantid dropped from right below the
radiant about 10 degrees towards the nne horizon." - Richard Kramer
2007 Dec 31 - The first Quadrantid has been detected by Sietse Dijkstra of the Netherlands.
2007 Dec 29 - Participating researchers have arrived in San Francisco Bay Area.
2007 Dec 28 - Podcast: How to observe the Quadrantids.
2007 Dec 27 - Feature story.
The elevation of the Sun and the Quadrantid shower radiant over the horizon during the 10-h Quadrantid MAC mission, for three different departure time scenarios [click on image for larger version]. Image courtesy: Jim Albers.
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2007 Dec 21 - The current Quadrantid MAC mission scenario would take the observers on a northern path out of NASA Ames Research Center in the afternoon of January 3, turn around at circa +68 degrees northern latitude, then turn back. The graphs show the position of the Quadrantid radiant throughout the flight for departure times in the range 2:45 to 4:45 pm PST. A 3:45 pm departure time would keep the radiant elevation of the Quadrantid shower nearly constant throughout the flight, a requirement of the mission, and observations would cover the period 1:30 to 9:30 UT, covering both extremes of predicted peak times. |
Flight path Quadrantid MAC mission:
2007 Dec 21 - Quadrantid MAC mission approved. Quadrantid MAC (Jan. 03-04) will for the first time map the flux profile of the annual Quadrantid shower under nearly unchanged observing conditions throughout the night. The data will be used to determine if the shower could have been created in 1490 AD.
2007 Aug 02 - Z. Kanuchova and L. Neslusan, in a paper in Astronomy and Astrophysics investigated the age of the shower and conclude that a significant fraction of Quadrantids could be older than 1490 AD.
2006 Sep 07 - A new model for the Quadrantid shower was calculated assuming the shower was created in around 1490 AD from 2003 EH1. The result shows a highly variable shower in peak time and peak rate from year to year. The results by Jeremie Vaubailllon and Peter Jenniskens were published in the book "Meteor Showers and Their Parent Comets".
2006 Mar 14 - Pavel Koten, Jiri Borovicka, Pavel Spurny, Steve Evans, R. Stork, and A. Elliott report in a paper in Monthly Notices of the Royal Astronomical Socity on a spectroscopic study of Quadrantid meteoroids. They conclude that the Quadrantids are similar to other meteor showers of cometary origin in some aspects, but have lost some of their volatile component, concluding that 2003 EH1 is a dormant comet.
2006 Jan 03 - Quadrantid shower summary by Spaceweather.com
2003 Dec 18 - Quadrantid parent body observed at ESO
2003 Dec 08 - Quadrantid parent body discovered
Jupiter's pulling and pushing causes an erratic shower at Earth. Quadrantid MAC aims to find out how erratic, which depends on the age of the shower. Distribution of meteoroid nodes near Earth orbit, in a model by Jeremie Vaubaillon, Caltech [click on image for larger picture].
Mission statement: Quadrantid MAC (Jan. 03-04) will for the first time map the flux profile of the annual Quadrantid shower under nearly unchanged observing conditions throughout the night. The data will be used to determine if the shower could have been created in 1490 AD.
Public interest: The Quadrantid shower is the year's biggest, but rarely seen because of bad weather and a radiant that is in underculmination at midnight, and because the shower is only a day wide. This year, the Moon is a just a waning sliver and best viewing is in the early morning hours on Friday January 4.
The catch: if the models are correct that the stream is young and Jupiter has a big influence because all grains still move closely together at aphelion, then observers in northern Europe and western Asia may see up to 50 meteors/hr under transparent clear skies, as much as a good display of the summer Perseids. However, if Jupiter's influence is small because the stream is older and much more dispersed at aphelion, and the shower shows up at the same time as it did in 1997, then the shower is best in the USA and Canada.
Calculate the rate of meteors at your site
What is the best location for viewing the 2008 Quadrantid shower? You can calculate the answer yourself with the handy FLUXTIMATOR Java Applet below. Choose the shower, the date, and a nearby location. Check your timezone carefully. The applet then calculates the expected shower rate.
Assuming the peak is at 2h00m UT
Assuming the peak is at 6h40m UT
The applet also allows you to see the difference between staying downtown or moving out into the countryside to a dark and clear location. All rates were calculated by taking into account the Moon light, which is not much of a disturbance during the Quadrantids.
Disclaimer: Make sure that Java is enabled. The duration, peak activity and time of the peaks are based on recent numerical models and past Quadrantid shower observations, and may be in error by several hours in peak time, and an unknown amount in peak rate.
How do our meteor showers originate?
The Quadrantid shower is typical of most other known meteor showers in that there is no known active parent comet. Searches for the parent body that produced the Quadrantids were fruitless until 2003, when Peter Jenniskens identified the near-Earth asteroid 2003 EH1 as the likely source of the Quadrantid shower. But 2003 EH1 is not an active comet. It is now thought that the stream originated from a breakup event less than 1000 years ago, possibly around 500 years ago. Between December 1490 and February 1491, observers in China, Korea, and Japan spotted a comet C/1490 Y1 that moved in the same plane as the Quadrantids. Could this have been the moment of breakup? And what type of breakup was involved?
One way to find out is by measuring how much the dust has been perturbed by the planet Jupiter, which passes the stream at aphelion, where the meteoroids move slowest. Jupiter's influence is large and models (see figure above) predict that the stream should vary significantly in activity and duration from year to year. Unfortunately, the narrow shower (FHWM = 8.5 hours) and radiant in underculmination make this a very difficult shower to observe by all techniques. The only way to keep the observing conditions more or less constant is by flying along with the rotating Earth and view the shower from near the Arctic.
Possible shower profiles. The potential level of variability in the Quadrantid shower flux profile from year to year.
The predictions
What do we expect? There is little agreement among astronomers about the shape and peak time of the shower. In 1997, the shower appears to have peaked at solar longitude 283.20, which would translate to 4 January 2008 at 07:37 UT. Similarly, the International Meteor Organization puts the peak time around 06:40 UT. If this holds, the shower should be strongest in the early morning hours over the Eastern USA. The Fluxtimator applet above shows how the rates would look in that case (select "10 Quadrantids 06:40").
However, scarce past observations of the Quadrantids determined peak times that varied from year to year over a period of about 8 hours. For 2008, our best model for dust ejected during a breakup in 1490 predicts a peak at about 4 January at 02h UT. In that case, the best viewing would be over Europe and western Asia, instead. The Fluxtimator applet above shows how the rates would look in that case (select "10 Quadrantids 02:00").
The range of possibilities is illustrated in the figure above. To cover all possible shower peak positions, calls for a day with no sunrise. To be sure we cover all possibilities, we would need to cover at least the period 0 - 12 UT to cover the peak and more to sample enough of the flux profile to be certain of it.
LINKS:
NASA Ames
Research Center missions website
Ursid MAC mission website
Aurigid MAC mission website
I.M.O. Meteor Shower Calendar
Gary Kronk's Meteor Shower's online page
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Flux
