MAPS August issue cover: The October 17, 2012, Novato meteorite fall in images taken from Santa Rosa by Robert P. Moreno, Jr., compliation by J. Albers and P. Jenniskens. [Higher resolution version]
2014, August 15 - Two manuscripts from a consortium study of the Novato meteorite will be published in the August issue of the journal Meteoritics and Planetary Science. [Manuscripts online at EarlyView] [NASA press release]
July 22, 2014 - Naked eye observers were disappointed by the poor showing of the May 24 Camelopardalids meteor shower from the close passage of comet 209P/LINEAR to Earth last month, but the weak activity of this never-before-seen shower now has scientists excited. An analysis of airborne and ground-based observations by Peter Jenniskens, published in the latest issue of the Journal of the International Meteor Organization, finds that this comet's meteoroids were unusually fragile and the shower was dominated by meteors too small to see with the naked eye. The dust encountered by Earth in May was more than a century old. One explanation for the lack of large meteoroids is that they did not survive the harsh conditions of space. [Manuscript]; [Press Release]
Map of glass damage in Chelyabinsk Oblast. Fireball moved from right to left. Dots are villages and towns in the area, marked red or orange when glass damage occurred. Yellow dots are the locations where meteorites were recovered. Gray area shows predictions of overpressure from asteroid impact models. From: Popova et al., Science Vol. 42 (2013).
2013, November 6 - Science published today a report on the Chelyabinsk meteoroid impact that describes the results from a Russian Academy of Sciences fact finding mission in the weeks after the impact, led by Dr. Olga Popova of the Institute for Dynamics of Geospheres of the RAS and Vacheslav Emel'yanenko of the Institute of Astronomy of the RAS in Moscow. NASA Ames and SETI Institute meteor astronomer Dr. Peter Jenniskens participated in this effort as outside expert and coordinated the study of the recovered meteorites. Now, the report led by Popova and Jenniskens, with contributions by 57 other researchers from nine countries, gives a detailed picture of all aspects that contributed to how the shockwave was created that caused the damage on the ground: how fast the meteoroid entered the Earth's atmosphere, how its kinetic energy was dissipated, and how processes that happened 4.4 billion years ago on the asteroid parent body contributed to determining the material properties of this meteoroid that made it break the way it did. Thanks to incredible local observations of this event, Chelyabinsk is expected to be a gold standard for asteroid impact modeling long into the future.
2013, August 1 - A paper describing the discovery of the February epsilon Virginids from CAMS data was published in the Journal of the International Meteor Organization. This was SETI REU student Kathryn Steakley's first science paper.
Steakley K., Jenniskens P., 2013. Discovery of the February Epsilon Virginids (FEV, IAU#506). JIMO 41, 109-111.
2013, June 1 - A paper describing the nu Cygnids from CAMS data was published in the Journal of the International Meteor Organization.
Jenniskens P., Haberman B., 2013. "Thatcher's Ghost": Confirmation of the nu Cygnids (NCY, IAU#409). JIMO 41, 75-76.
2013, April 1 - A paper describing the discovery of the upsilon Andromedids from CAMS data was published in the Journal of the International Meteor Organization.
Holman D., Jenniskens P., 2013. Discovery of the Upsilon Andromedids. JIMO 41, 43-47.
2013, April 1 - An overview paper of now established meteor showers was published in the proceedings of the 2012 International Meteor Conference.
Jenniskens P., Gural P. S., Holman D., 2013. The established meteor showers as seen in video meteoroid orbit surveys. In: Proceedings of the International Meteor Conference, La Palma, Canary Islands, 20-23 September 2012, Gyssens M., Roggemans P., eds., International Meteor Organization, pp. 38-43.
2013, February 1 - A paper describing observations with two CAMS units in the Netherlands was published in the Journal of the International Meteor Organization.
Johannink, C., 2013. Results for a CAMS double-station video observation Meterik - Gronau. JIMO 41, 14-21.
Photo of Sutter's Mill fall by Lisa Warren.
2012, December 21 - Today in the journal Science, 70 authors published a report on the first two months of studies on the fall of the Sutter's Mill meteorite and its properties. Sutter's Mill was found to have arrived from the asteroid belt recently, on an orbit that still points to its source region. The meteorites are unusually diverse, composed of rocks within rocks, the first time a CM chondrtie is clearly a regolith breccia. The rapid recovery, thanks to the first detection of falling meteorites from a carbonaceous chondrite fall by Doppler weather radar, provided the most pristine look yet at the former surface of the CM chondrite parent body asteroid.
[Supporting Online Materials]
2012, October 1 - Confusion betwen the Northern Delta Aquariids and the Northern June Aquilids is resolved. Both showers have a perihelion close to the Sun, but they have slightly different inclination. The Northern Delta Aquariids is the August shower, the Northern June Aquilids is active in late June and all of July.
D. Holman, P. Jenniskens, 2012. Confirmation of the Northern Delta Aquariids (NDA, IAU#26) and the Northern June Aquilids (NZC, IAU #164). JIMO 40, 166-170.
December 1-8 (4250 SonotaCo and 3240 CAMS)
2012, July 20 - The September issue of Sky and Telescope features an overview article about the first year of observations by CAMS. A series of maps combining CAMS and SonotaCo data identify the first 64 established meteor showers by the International Astronomical Union.
2012, June 1 - The link between the Marsden Sunskirter comets and the Daytime Arietids is confirmed. CAMS observations in the pre-dawn hours of early June demonstrate that the semi-major axis of the Daytime Arietids is similar to that of the Marsden Sunskirter comets, as opposed to the low value derived from earlier radar observations.
P. Jenniskens, H. Duckworth, B. Grigsby, 2012. Daytime Arietids and Marsden Sunskirters (ARI, IAU#171). JIMO 40, 98-100.
2012, February 1 - A paper describing the confirmation of the July Gamma Draconids from CAMS data was published in the Journal of the International Meteor Organization.
D. Holman, P. Jenniskens, 2012. Confirmation of the July Gamma Draconids (GDR, IAU#184). JIMO (in press).
2011, December 20 - We have discovered why we see meteors flash through the night sky while they seemingly rain down on us gently at the same time! In a paper published in the December 20 issue of the Astrophysical Journal, David Nesvorny, Diego Janches, David Vokrouhlicky, Petr Pokorny, William F. Bottke, and Peter Jenniskens reconciled models of the zodiacal cloud with radar observations, revealing a game of hide and seek and an interesting identity switcharoo.
[Press release (Dec20)]
2011, December 14 - During routine low-light level video observations with CAMS (Cameras for Allsky Meteor Surveillance) in the period April 26 - May 7, we detected the April Rho Cygnids (ARC), a meteor stream discovered by the Canadian Meteor Orbit Radar (CMOR) project in the years 2002 - 2009. The stream is included in the IAU Working list of Meteor Showers as shower #348, awaiting verification. CMOR data show ARC activity from April 25 - May 4, peaking on April 28. We detected this shower on all dates, peaking on April 28 and May 1 in 2011. The orbital parameters we found match the CMOR data. Our mean orbital elements are (N = 29): q = 0.844 +/- 0.034 AU, 1/a = 0.18 +/- 0.10 1/AU, i = 69.7 +/- 2.8 deg, w = 130.4 +/- 6.2 deg, and Node = 39.9 +/- 2.9 deg. The parent body of the ARC remains unknown, but from the recent evolution of the stream, we provide a range of possible current orbits.
M. Phillips, P. Jenniskens, B. Grigsby, 2011. Confirmation of the April Rho Cygnids (ARC, IAU#348). JIMO 39, 131-136 [PDF]
2011, November 10 - An overview paper "CAMS: Cameras for Allsky Meteor Surveillance to validate minor meteor showers", by P. Jenniskens, P. S. Gural, B. Grigsby, L. Dynneson, M. Koop, and D. Holman, has appeared in print in the journal Icarus. It contains the analysis of the first batch of CAMS data. [PDF]
From the peer review report: "Technically, the paper is very well laid out. Following a summary of the scientific rationale behind the observations, the authors go to (justifiably) great lengths to quantify the capabilities of the hardware and data reduction procedures and to demonstrate that these can carry out science-grade observations (which they do). They report on their confirmation or rejection of recently claimed new meteor showers in support of the latter objective."
P. Jenniskens, P. S. Gural, B. Grigsby, L. Dynneson, M. Koop, and D. Holman, 2011. CAMS: Cameras for Allsky Meteor Surveillance to validate minor meteor showers. (Icarus 216, 40-61).
This +2 magnitude February eta Draconid was filmed by
Peter Jenniskens with one of the low-light-level video
cameras of the Cameras for Allsky Meteor Surveillance (CAMS)
station in Mountain View, California, at 07:59:24 UT on February 4, 2011.
2011, July 10 - The Central Bureau for Astronomical Telegrams of the International Astronomical Union today issued this TELEGRAM announcing the discovery of the February Eta Draconids.
Although CAMS was designed to confirm previously discovered showers, a meteor outburst was detected in CAMS February 4 data from Fremont Peak (Rick Morales, Loren Dynneson, et al.) and Mountain View (Peter Jenniskens). This is the first new shower discovered by CAMS. It is also a very unusual shower, of a type that only occurs once or twice every sixty years and is caused by the dust trail of a (still to be discovered) Earth-threatening long-period comet. The new shower was named the February eta Draconids and is now listed as shower 427 in the IAU Working List of Meteor Showers. A paper on this discovery was submitted to the Journal of the International Meteor Organization [[read pre-print]].
P. Jenniskens, P. S. Gural, 2011. The discovery of the February eta Draconids (FED, IAU#427). JIMO 39, 93-97.
The dust between the planets that scatters sunlight our way is not from the asteroid belt (depicted here in green), but from periodically disrupting comets that spend much of their time near the orbit of Jupiter ("V"), according to calculations by Nesvorny and Jenniskens. Illustration: SWRI/SETI Institute (Andrew Blanchard, David Nesvorny and Peter Jenniskens). Media: this image may be used for reporting on this work. Click on image for larger version.
2010, April 20 - [Press release] The eerie glow that straddles the night time zodiac is no longer a mystery. First
explained by Joshua Childrey in 1661 as sunlight scattered in our direction by dust
particles in the solar system, the source of that dust was long debated. In a paper to
appear in the April 20 issue of The Astrophysical Journal, David Nesvorny and
Peter Jenniskens put the stake in asteroids. More than 85 percent of the dust,
they conclude, originated from Jupiter Family comets. [Read the paper]
Zodiacal light and Jupiter, from near Tarcoola in southern Australia in the pre-dawn hours of June, 2010. Photo using 180 degree fisheye lens by Chris Kitting, CSU East Bay.
Top: Comet 169P/NEAT in an image by P. Birtwhistle on August 8.9, 2005, when the object showed a faint comet tail [Photo: P. Birtwhistle]. The object was discoverd in 2002 by the NEAT survey, categorised as asteroidal, and designated 2002 EX12. During the next return to Sun on 28 July 2005 (the comet taking about 4.2 years to circle the Sun), Brian Warner at the Palmer Divide Observatory first noticed that the object had developed a tail.
In the most recent 2010 return, the object looked mostly asteroidal again. Bottom picture shows a photograph on February 17, 2010, by Bernhard Haeusler, Maidbronn, Germany. Photo: Bernhard Haeusler.
Top: An alpha Capricornid photographed by Casper ter Kuile (Dutch Meteor Society) on August 4, 1995, at 23:16:27 UT. Breaks in the meteor trail are from a rotating camera shutter. Photo: Casper ter Kuile, DMS.
Bottom: A -5 magnitude alpha Capricornid photographed on July 29, 1990, at 23:09:30 UT by Klaas Jobse, Dutch Meteor Society. Photo: Klaas Jobse, DMS.
Media: These images may be used in reports. Please give the photo credit listed with each picture. Click on images for larger version.
2010, March 31 - It's parent body now identified, meteoroid stream models show that the main dust mass is moving towards Earth. The alpha Capricornid shower may become an annual meteor storm come 2370 AD, says a new paper by meteor astronomers Peter Jenniskens and Jeremie Vaubaillon in the Astronomical Journal Vol. 139 (2010) pages 1822-1830 (now online). [Read the paper]
2010, January 15 - In a paper submitted to Meteoritics and Planetary Science, the origin of the Geminid meteor shower is investigated. This work is part of a series of papers on the study of the meteorites recovered from asteroid 2008 TC3.
2009, November 17 - The 2009 Leonid shower outburst was observed from Nepal by Peter Jenniskens and Jeremie Vaubaillon. The outburst occurred much as predicted, but the exact time of the peak and the duration of the shower is expected to shed light on the past orbit of comet 55P/Tempel-Tuttle and the epoch of ejection of the observed dust. [YouTube report]
2008, October 07 - A small asteroid, named 2008 TC3, was discovered to be on an impact course with Earth. It impacted the Nubian Desert of Northern Sudan in the early morning of October 7. Two months later, on December 6, Peter Jenniskens and Muawia Shaddad searched the area in the company of 45 students and staff of the University of Khartoum and recovered remains of asteroid 2008 TC3. Results were published in a paper in Nature. Additional searches commenced in late December 2008, February/March 2009, and in December of 2009, following the 2008 TC3 workshop at the University of Khartoum [More here].
2008, August 02 - The parent body of the kappa Cygnid meteor shower is identifed as 2008 ED69 in a paper by Peter Jenniskens and Jeremie Vaubaillon. [Read the paper]