Predictions & Information

The Perseids are one of the most exciting and dynamic meteor showers; producing fast-moving shooting stars throughout July and August. Based on IMO observations from recent years, we expect the "normal" peak of ~100 meteors per hour to occur in the night of August 12-13 between 18h and 7h Universal Time.

The shower surprised on several occasions over the last two decades by showing outbursts of 150 to 400+ meteors/hour due to the Earth passing through regions of higher density in the dust stream (e.g., ZHR ~200 last year). Simulations by Jeremie Vaubaillon and Mikhail Maslov indicate that we may again encounter 'dust trails' this year, left behind when the parent comet passed the Sun in the years 441, 1479 and 1862. Unfortunately, the distance to the nearest trails is expected to be somewhat larger than last year, and their timing is thought to favour only regions around the Pacific Ocean. However, the predictions are uncertain and worldwide observations by amateur astronomers are required during all nights near the maximum to verify and improve the models.

New Moon on August 10 creates perfect conditions to observe the shower. Perseids are best observed after local midnight, when the radiant gains altitude in the sky. In fact, highest rates are visible towards the early morning hours when the radiant reaches its highest point. We strongly encourage visual observations to be made according to the standard procedure and submitted through the online report form. Such observations will automatically be included in the ZHR activity graph below (click for more results).

Activity graph below is updated every 15 minutes - click for details.

The Lyrids are expected to peak on 2010 April 22 around 17h UT (ZHR ~20). Past observations have shown the maximum time to be variable from year to year; in 2010 the peak could occur between 9h and 21h UT on April 22, but observations in the days before and after the peak are also worthwile. The radiant of this shower, between Lyra and Hercules, rises during the night. Watches can be usefully carried out from about 22h30m local time onwards from mid-northern sites, but only from well after midnight from the mid-southern hemisphere. On April 22, the waxing gibbous Moon will set between 1h and 2h UT for most northern sites. More information about this shower can be found in the 2010 Shower Calendar.

Visual observations can be reported through the Report Form and are highly appreciated. The observations are automatically included in an automated ZHR graph.

The Geminids is one of the finest, and probably the most reliable, annual meteor shower. Activity exceeds 100 meteors per hour around December 14, with meteors radiating from a point near Castor in constellation Gemini. Geminids are slow, bright and occasionally colorful. Many observers consider the shower to be more spectacular than the famous Perseids in August, but the Geminids are less widely known because of the cold and often clouded December nights in the northern hemisphere.

This year the peak is expected in the morning of December 14 (5h00 UT), coinciding with a perfect new Moon. Many tens of meteors per hour will be visible in the nights surrounding December 14, with highest rates occuring in the hours after local midnight when the radiant reaches its highest altitude in the sky. More information on the observing conditions can be found in the shower calendar.

An electronic report form is available to submit your visual observations, which will automatically be included in a ZHR activity graph. Please report short counting intervals throughout December 13-15, preferably 10 to 20 minutes, even when the activity appears low!

This year may produce another enhanced return of the Leonid meteor shower, with ZHR hourly rates expected to exceed 150+ according to independent studies by Jérémie Vaubaillon, Mikhail Maslov, Esko Lyytinen, Danielle Moser, David Asher, Mikiya Sato and their respective collaborators (click the links for details). The main peak(s) are expected to occur in the night of November 17 to 18 around 22h00 UT (= 17h00 US Eastern, 23h00 Central Europe, 3h30 India, 6h00 Beijing), although variable activity may happen at almost any stage between November 16 and 18. Continuous monitoring is necessary. Leonids are generally only visible after local midnight from any longitude, with the exception of some long Earth-grazing Leonids before midnight when the radiant is still very low. Consult the shower calendar for more background.

Scientists depend strongly on visual observations by volunteers to test the theoretical models and improve future predictions. For more information on contributing your own observations, please consult the observing instructions and the instructions for filing a report. The IMO offers an electronic report form to submit your observations, and will automatically include them in the ZHR activity graph shown on the right.

October's new Moon perfectly favours the Orionids at their peak in 2009. The shower's radiant, near the celestial equator, is at a useful elevation by around local midnight in either hemisphere, so most of the world can enjoy the shower. The shower peaks on October 21st, but has previously been noted to have several lesser peaks, sometimes helping activity to remain roughly constant for several consecutive nights centred on this peak. Observers should be aware of this possibility and attempt to observe for multiple nights.

Previous years have produced unexpectedly strong Orionid rates, with ZHRs better than the normal peak seen on two or three consecutive nights, at best up to 50-70. It will be interesting to see what takes place this year.

Visual observations can be reported through the Report Form and are as always highly appreciated. The observations are automatically included in an automated ZHR graph.

Although the major northern hemisphere Perseids are badly affected by the last quarter Moon near their best this year, there is the possibility they may produce somewhat increased rates. The usual maximum is due around August 12, 17h30m-20h00m UT, but Esko Lyytinen suggests we may encounter the 1610 Perseid trail earlier on August 12, around 9h00m UT (λo = 139°661). This could produce activity additional to the normal Perseid ZHRs then of a few tens, maybe up to a hundred. Mikhail Maslov confirmed this but for 8h00m UT and with only 10-15 meteors per hour. Both reseachers further suggest that rates overall could be enhanced above usual by the proximity of the annual stream's core.

The 19th century trail should pass roughly 0.003 astronomical units inside the Earth's orbit at λo = 139°499, so around 5h UT on August 12, though it may add less than 10 (according to Lyytinen) or up to nearly 100 (according to Maslov) to the ZHR at that point. Naturally, information to verify what takes place will be very valuable despite the Moon, so visual observers are encouraged to try to follow as much of what happens over the possible Perseid maxima as practical.Visual observations can be reported through the Report Form and are highly appreciated. The observations are automatically included in an automated ZHR graph.