Published: 2014-05-21 17:46:00
Updated: 2014-05-23 15:22:56
Posted May 21, 2014
Updated May 23, 2014
By Tony Rice
On Friday night and Saturday morning (May 23-24), Earth will travel through a trail of sand-grain sized debris ejected by a comet over 200 years ago. North America will get the best view of the resulting meteor shower, known as the Cameloparadalids for the dim constellation between the big and little dippers where meteors appear.
This could be the best of the year exceeding the 100+ expected each year from the Quadrantids (January), Geminids (December), and Perseids (August).
Because this is a new meteor shower, no one knows for sure how many we will see. Early predictions suggested the possibility of a meteor storm (1000 meteors per hour.) Fifteen computer models from six different research teams since then have converged on a Zenith Hourly Rate (ZHR) of 200 per hour.
Russian meteor expert Mikhail Maslov predicts a ZHR of 100-400 adding, "storm levels are far from being excluded." We could also see nothing.
Unlike most meteor showers that are visible around the same time each year, the Camelopardalids aren't something you can put off until next year. Comet 209P/LINEAR has an irregular orbit, in part due to Jupiter's gravitational influence according to William Cooke, head of the Meteoroid Environment Office at NASA's Marshall Space Flight Center. Researchers focused on 15 separate visits by the comet between 1798 and 1979 as a source for this weekend's meteors.
Observations made by the Catalina Sky Survey telescopes in Arizona and Australia along with observations made by astrophotographer Michael Jager in Namibia were used to generate computer models of the comet's history. This led to detailed predictions on when we would pass through the densest portions of the tail.
This led to predictions of a peak between 2 and 4 a.m. here on the East Coast. However, models indicate that we will be passing through rapidly increasing numbers of particles beginning around sunset. Even if you aren't planning to set your alarm for the middle of the night, it is still worth stepping outside before turning in Friday evening. Allow yourself a few minutes for your eyes to adjust to the darkness and then look anywhere in the sky.
The comet's albedo (literally "whiteness" in Latin) also gives clues about what kind of meteors to expect. Quanzhi Ye and Paul Wiegert of The University of Western Ontario concluded, "the tail is dominated by larger particles." This could mean brighter, longer lasting meteors streaking through our skies. Albedo also shows that 209P/LINEAR is "currently transitioning from typical comet to a dormant comet." Which might make this the one and only appearance of the Camelopardalids.
The forecast couldn't be much better with clear skies and temperatures in the mid-50's overnight Friday into Saturday. As the show winds down just before sunrise, look to the east for the rising crescent moon followed closely behind by bright beautiful Venus.
Tony Rice is a volunteer in the NASA/JPL Solar System Ambassador program and software engineer at Cisco Systems. You can follow him on twitter @rtphokie.