Major Meteor Showers in 2005
2004 gave North American meteor observers some good highlights, provided that the local weather cooperated! A strong Perseid maximum, moon-free Geminids, and reliable displays from the Lyrids, Orionids and Leonids all contributed to a decent year. In addition, a predicted outburst from the normally absent June Bootids did indeed produce some nice meteors. Hopeful Draconid observers weren't so lucky; only a few possible shower members were reported.
In 2005, the Moon will be a major hindrance for many of the major-shower maxima. The Perseids are really the only shower that I can whole-heartedly recommend to the general public or the expectant first-time observer. Dedicated observers, on the other hand, will find several opportunities for decent rates despite moonlight and inconvenient hours.
Don't forget to consider the effect of radiant elevation when planning an observing session. Even if a shower is near its activity peak, you won't see a thing from it if the radiant is below your local horizon. In the case of a strong shower, you may expect a (very) few long "earthgrazing" meteors when the radiant is near the horizon, but even when the radiant has reached an elevation of 30 degrees you will only see half as many meteors as you would if it were at your local zenith. Most shower radiants are highest during local morning hours, often just before twilight begins. That's usually when you want to observe, although occasionally a rising Moon or a sharp activity peak will suggest an earlier time. Best viewing windows are suggested for each shower.
Vagaries of meteor activity, your personal ability to perceive meteors, and local sky conditions may all dramatically affect the rates you observe. Sky conditions to consider include weather and light pollution. If you can't see the summer Milky Way in Cygnus on a moonless night when this region of the sky is overhead, you probably won't see much from even the strongest annual showers. Clear, dark skies are essential for observing meteors. More shower meteors are visible from a dark site, and sporadic (random) meteor rates are enhanced greatly.
QUADRANTIDS (maximum January 3, 12h UT [4am PST; 7am EST])
Moon: Last Quarter (moderate to major interference)
Best viewing window: Monday morning, January 3. Roughly 3:00am local standard time until morning twilight gets too bright (roughly 6:00am local standard time at 40 degrees N; earlier for southerly locations and later for northerly ones).
Recommended for: Dedicated meteor observers, and those who want to learn the hard way.
Peak Quadrantid rates rival those of the Perseids and Geminids. However, the shower has a very sharp and variable maximum (possibly several hours later or earlier than the predicted time given above), and early January often features unforgiving weather. That makes this a difficult shower to catch at its best. 2005 will add the complication of a Last Quarter Moon. Dry, clean air will minimize the skyglow from the Moon. If you have an unobstructed view to the north and northwest, you can put the Moon behind you and possibly exclude it from your field of view. Quadrantid rates are rather unpredictable; from the best sites, a competent observer might expect maximum rates of 15-30 Quads per hour on the morning of January 3, along with 5-10 other meteors. Observers in western North America are favored by the predicted peak.
Quadrantids are medium-velocity meteors, and some bright ones are often visible at maximum activity. The radiant is in a rather blank area surrounded by the constellation figures of Bootes, Hercules, Draco and Ursa Major (see radiant drift map). It is usually pointless to observe this shower in the evening, as the radiant lies near the horizon. That's doubly true this year, with a morning maximum predicted. The adjacent nights only produce a few shower members; the shower has a very short duration from about January 1-5.
2005 Quadrantid report: I had clear sky for three hours of observations on January 3. My best hour, centered at around 12:40UT, featured 29 Quadrantids.
LYRIDS (maximum April 22, ~10hUT [3am PDT; 6am EDT])
Moon: Nearly Full (major interference)
Best viewing window: Friday morning, April 22. Roughly 2:00am local daylight time until morning twilight gets too bright (roughly 4:45 local daylight time at 40 degrees N).
Recommended for: True die-hards only.
The Lyrids have produced a few exceptional displays in the past, but on a normal annual basis they are just barely a major shower. Typical maximum rates are 10-20 per hour. The time of maximum is rather variable; it's easy to miss it and observe even lower rates. Throw in a nearly full Moon as occurs this year, and you'll be lucky to see 3-5 Lyrids per hour. The Moon does get rather low for the last hour before morning twilight, so concentrate on that period if you really want to try to observe the Lyrids this year.
Lyrids produce fairly fast meteors with a reputation for being faint on average (not auspicious in view of the bright moonlight). Nights adjacent to the peak will be even less worth watching.
Moon: Waning Crescent (minor to no interference)
Best viewing window: Friday morning, May 6 (adjacent mornings may be just as good at the same local times). Focus on the last hour or so before twilight gets really bright (depends on your latitude and also on your longitude with respect to the center of your time zone). At latitude 42.6 degrees North, I've had my best results from about 3:40-4:40am local daylight time. At latitude 35 North, you might want to begin 15 minutes earlier and end up to a half-hour later.
Recommended for: Southern observers; also northerners who want a challenge.
The Eta Aquarids would produce maximum rates of >50 per hour if we could see them with the radiant high in a dark sky. In the northern temperate latitudes, we don't get close to that. We get just a small taste of them in an intricate dance just before dawn. At 40 degrees North, the radiant is only about 15 degrees up when twilight begins. If you could get those conditions for an hour, you might see 10-15 ETAs. However, everything's changing. Before that time, you're seeing fewer shower members because the radiant is lower. After that time, the radiant is higher and rates keep rising, but all too soon the full brunt of twilight wipes out your dark skies. You're fortunate indeed if you see 10 ETAs in an hour, along with about 5 sporadic (random) meteors. The farther south you are, the better you will fare.
The low radiant elevation means that the earliest ETAs you see will be "earthgrazers": long, relatively slow and often tracing paths along the horizon. Bright earthgrazers are spectacular. Unfortunately, because of their greater distance from the observer, low earthgrazers tend to be faint. As the radiant gets a bit higher, the ETAs take on more of their typical appearance: fast meteors, bright on average and often leaving a glowing train. You'll only catch a few of them, though, because dawn is approaching. One good thing about the Eta Aquarids is the long duration of the shower: rates near maximum may be maintained for several days. The shower also seems to fluctuate irregularly, so you could easily hit either a spurt or a lull. Try the mornings of April 5, 6 and/or 7 this year, and maybe you'll get lucky.
SOUTH DELTA AQUARIDS (maximum July 28 [broad])
Moon: Last Quarter (moderate to major interference)
Best viewing window: Hard to pick one. Perhaps Saturday morning, July 30, would be the best. By this time, the Moon has shrunk to a thick crescent and rises after midnight for most locations. 1:00-4:00am local daylight time would probably be the best hours, with a view toward the west. No guarantees, though. Southern Hemisphere observers have the radiant high enough to observe before the Moon rises.
Recommended for: Pretty much die-hards only, although southern observers have it a bit easier.
The South Delta Aquarids are barely a major shower from 40 degrees N. They are part of a complex of radiants in Aquarius, Capricornus and Piscis Austrinus, all of which combine with sporadic and early Perseid activity to provide a nice display of meteors on moonless mornings in late July. Unfortunately, this year those mornings aren't moonless, and the shower will be marginally interesting at best. The stream normally produces about 5-10 meteors/hour, with overall activity of about 30/hour under good conditions. Cut those numbers in half this year due to the moonlight interference. The South Delta Aquarids are medium-speed meteors, and tend to be faint on average.
PERSEIDS (maximum August 12, 17h UT [10am PDT; 1pm EDT])
Moon: First Quarter (minor interference)
Best viewing windows: Thursday evening into Friday morning, August 11/12, from 11pm until morning twilight gets too bright (4:30am or so). The best hours will be the morning ones. As a second option, Friday evening into Saturday morning, August 12/13, from 11pm until 4:30am. Rates may be fairly steady throughout the night.
Recommended for: Just about anyone in the northern temperate latitudes (but a dark-sky site helps a lot)!
The Perseids are definitely the most promising and accessible of this year's meteor showers. The shower has a very long duration, from about July 15 through August 25. Only on a few mornings around the August 12 peak does the shower become really prolific, however. From latitude 40 degrees N, the radiant is above the horizon as the sky starts to get dark. Rates are pretty low then, and this year the First Quarter Moon will be a bit of a deterrent to early observing. The Moon will set before midnight, however, and the Perseids should rule the rest of the night.
West Coast USA observers in particular should try to hit the Friday morning hours of August 12; expect 40-80 Perseids/hour from a truly dark site before morning twilight begins. The best place to observe the peak should actually be eastern Asia. East Coast observers may see rates in the lower part of that range. Friday night into Saturday morning should be productive as well, with peak rates over 40 Perseids/hour from dark sites and the East Coast favored at least slightly.
While these are the absolute best times to view the Perseids, the adjacent mornings (Thursday and Sunday) will also provide good rates (probably exceeding 20 Perseids/hour). View during the last couple of hours before morning twilight for best results. Die-hard observers can follow the stream's off-peak dates throughout early and mid-August without moonlight interference.
Perseids are fast meteors and tend to be fairly bright on average. An occasional fireball is seen, but these seem to depend on the luck of the draw. Perseids are by no means the only meteors visible; in the morning hours, sporadics and several minor showers combine to add ~10-15 meteors to the total. All of this assumes a dark site with the summer Milky Way blazing away. If you've got light pollution problems, both your Perseid and non-Perseid rates are going to be much, much lower. So, get out to a rural or remote site where you can enjoy the Perseids!
ORIONIDS (maximum October 21 [broad and irregular])
Moon: Waning gibbous (major interference)
Best viewing window: None, really. The radiant is well-placed from about 1 or 2am until morning twilight, but this year is all about the Moon.
Recommended for: True die-hards only.
The Orionids can produce some interesting activity from October 17-25. Unfortunately, this year the Moon is full at the start of that period and proceeds to march eastward. It remains high in the sky and isn't far from the Orionid radiant during the shower's normal maximum. There's probably not much point in trying to view this year's Orionids.
Moon: Waxing crescent to waxing gibbous (minor to moderate interference)
Best viewing window: Between 11pm and 2am local standard time on any night in early November; late October may be productive as well.
Recommended for: Observers who don't mind seeing low rates in exchange for the possibility of a spectacular fireball or two.
The Taurids produce maximum rates of about 5-10/hour. The shower has a complex double radiant. For 2005, it has been suggested that there may be an increase in the number of bright and/or fireball-class Taurids. Taurids are rather slow meteors; bright ones are often vividly colored and may be spectacular. Usually, they are noticed casually while undertaking other observations. This year's display may or may not be worth watching in and of itself; the Taurids are included here to give fair warning.
Moon: Nearly full to waning gibbous (major interference)
Best viewing window: Thursday through Saturday mornings, November 17-19; the last hour or so before morning twilight. Maybe Monday morning, November 21 after 1am local time.
Recommended for: True die-hards only.
Forget what the Leonids have done recently. The storms are over, even if the media still had to hype the shower in 2004. The shower's background maximum should be about 10-20/hour, although enhancements of 30 or more have been seen the past couple of years. It would be interesting to see whether this pattern holds for 2005, but any observations will be difficult to undertake because of the bright Moon. In 2004, fewer but brighter Leonids were seen on November 17, near the nominal "maximum". A stronger shower of fainter meteors was seen on November 20 in 2003 and November 19 in 2004 (roughly the same time due to leap years). Some predictions were made for enhanced activity, but what was seen didn't correlate too closely with the predictions. For 2005, Mikhail Maslov has found a possible activity enhancement on November 21. The model predicts a peak ZHR of around 18 at maximum. The exact peak at around 1:10 UT will not be observable from North America, but modeling suggests a long-duration event that would still be producing meteors during our favored morning hours. So, dedicated observers might want to keep an eye on the Leonids for curiosity's sake. The Moon will certainly reduce rates (probably to <10/hour), and make it difficult to draw any conclusions.
GEMINIDS (maximum December 14, ~4h UT [December 13; 8pmPST or 11pm EST]) (radiant drift map from IMO)
Moon: Full (major interference)
Best viewing windows: Tuesday morning, December 13; the last couple of hours before morning twilight. Also, the entire night of Tuesday evening/Wednesday morning, December 13/14 after about 8pm local time.
Recommended for: Dedicated meteor observers, and those who want to learn the hard way.
The Geminids are a beautiful, prolific and reliable shower. What a shame that their 2005 return has to coincide with Full Moon. Dry, clear air will help a lot with the lunar glare, but it will be difficult to achieve maximum rates of 20 Geminids/hour even at the best sites. The Moon will be high in the sky for most of the night. In the last couple of hours before morning twilight, it's fairly low. During those hours, you may be able to put it behind you and out of your field of view. During the rest of the night, you'll need to find some way to block the Moon and the bright sky surrounding it without obstructing the rest of your field of view. I've used objects like my hand, chairs, cars, trees and telescopes to do so during past showers.
Geminids are medium-speed meteors. Most of them don't leave glowing trains, but the brighter ones are often colored (yellow, green and blue are most common). The shower has a skew rate profile, with activity dropping quickly after maximum. At the same time, the proportion of bright meteors is higher during and after maximum than on pre-maximum nights. The Geminids are worth watching for one or two mornings before the peak; there will be slightly less moonlight interference, and some locations will get a short moonless period before morning twilight.
Note: I observed the Geminids on three different nights under variable conditions. The shower seemed a bit weaker and fainter than usual during the night of maximum, although it was hard to draw any conclusions because of the sky conditions. I did manage 29 Geminids in 50 minutes during the relatively Moon-free period just before morning twilight on Tuesday, December 13.
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Other Sources of Meteor Activity
The major showers listed here are fairly reliable and occur every year. The "best viewing windows" indicate the local times when the highest rates should be visible. However, meteor activity is visible on any clear night. Random sporadic meteors, minor showers, and major showers near the beginning or end of their activity period all contribute to this "background". For the Northern Hemisphere, there is a general pattern of lower rates during the first half of the year and higher rates during the second half, but rates vary greatly from hour to hour, day to day, and observer to observer. Occasionally, unexpected high activity occurs. It is up to the observer to objectively describe what was seen. In many cases, high activity may be ascribed to randomness. At other times, many of the meteors seen may be attributed to a common radiant.
A couple of periodic showers with a small potential of producing high activity in 2005 are the October Draconids (Giacobinids) and the November Alpha-Monocerotids. Very few if any meteors are seen from these streams in a typical year, but outbursts have occurred from both in the past. For the Draconids, the 2005 intrigue stems from the return of the parent comet 21P/Giacobini-Zinner. In past years, outbursts have often been associated with the nearness of the parent comet, but due to recent research we now see a more complex picture of debris trails and planetary perturbations. Newer models seem to rule out any major Draconid outburst in 2005, but the nights of October 7/8 and 8/9 should be monitored by dedicated meteor observers. Note: The 2005 Draconids did produce a minor outburst for Asian and European observers: ZHR~30.
Four outbursts of the Alpha-Monocerotids have been observed. The years were 1925, 1935, 1985 and 1995. These were always very brief events, and other intervening outbursts could certainly have been missed. Only the 1995 outburst, lasting a half-hour and containing a sharp peak of up to 7 meteors/minute, was really well-observed. Does the pattern add up to a 10-year periodicity and predict another outburst in 2005? Or, are the "5's" just an odd coincidence in a complex picture that we haven't yet grasped? A couple of respected researchers suggest the latter (Lyytinen and Jenniskens, 2003), and say that 2005 will not produce much. If something is to be seen from this shower, the morning hours of November 21 are the best bet. Unfortunately, there will be a bright waning gibbous Moon in the sky.
Other Meteor Shower Info.
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General shower attributes, radiant maps and predicted times of maximum are from the International Meteor Organization's 2005 Meteor Shower Calendar. All other on-site text and contents are Copyright 2004, 2005 by Wes Stone and may be reproduced for not-for-profit use so long as credit is given.
