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The Lyrids Are Coming!
SeaDour writes "The year's first meteor shower, the Lyrids, will peak in the pre-dawn hours of April 22nd when the Earth plows through the debris trail of Comet Thatcher at a relative velocity of 49 km/s (110,000 mph). Lyrids usually aren't as numerous as other showers (such as the famed Leonids), but they're well-known for their spectacular tails; you can expect to see about 5-20 meteors per hour, depending on the severity of your local light pollution. Unfortunately, my current location in the midwest under stormy skies puts me at a bit of a disposition, but hopefully some other Slashdotters can share their observations with us tomorrow."
This show is worth a watch! It's not as high-profile as the August show, but MAN it's spectacular!
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"The Lyrids are best seen between about 2 a.m. and daybreak local time, regardless of where you live, astronomers say"
Missed the 3rd paragraph I take it?
Chaos, panic, disorder...my work here is done.
Hehe, I usually try to stay away... but RTFA!
The Lyrids are best seen between about 2 a.m. and daybreak local time, regardless of where you live, astronomers say.
City and suburban dwellers will see significantly fewer of the meteors than those in rural areas away from all light pollution. The shower is not visible from the Southern Hemisphere.
Being a non-astronomer I guess I assumed that you would have to wait until the side of the earth you were on faced towards the area of space where the comet was. How does someone on the far side of the earth see the meteors? Does the fact that they are visible at or before dawn across the world imply that the comet's position is relatively static compared to the position of the sun?
Read Pynchon.
Meteor Shower Peaks Before Dawn Thursday
By Robert Roy Britt
Senior Science Writer
posted: 07:42 am ET
21 April 2004
The annual Lyrid meteor shower peaks before dawn Thursday, April 22. Skywatchers in the Northern Hemisphere with dark skies away from city lights could see anywhere from 5 to 25 shootings stars per hour, or one every few minutes.
The timing of this year's version is good, because the Moon just passed its New phase and is out of the picture, its otherwise bright light not a factor.
The Lyrids are best seen between about 2 a.m. and daybreak local time, regardless of where you live, astronomers say. That's when the shower's radiant -- the point from which they appear to emanate -- is highest in the sky. The Lyrid radiant is in the constellation Lyra, and very near to the bright star Vega.
Vega is easy to find. It's in the eastern sky but nearly overhead in the predawn hours. It is the brightest star in that region of the sky and the 5th brightest star overall.
Lyrid meteors can appear anywhere in the sky. But if you trace each one back, it will point toward Vega. The shower is a result of Earth passing through a trail of debris left by a comet called Thatcher, which last passed through the inner solar system in 1861.
The Lyrid event is typically modest -- not as busy as the November Leonids or the August Perseids. But they are still cherished by devout meteor observers.
"The Lyrids are the first major annual shower of the season," said Robert Lunsford of the American Meteor Society.
But this April shower sometimes generates a brief outburst, when the rate can climb to more than one a minute. Seasoned observers might notice that the Lyrids move more quickly than typical meteors. Bright and persistent trails are common with the Lyrids.
Most shooting stars are generated by bits no larger than sand grains that vaporize when they plow into Earth's atmosphere. An occasional bright fireball is sometimes sighted amid the Lyrids, caused by debris perhaps the size of a pea or marble.
City and suburban dwellers will see significantly fewer of the meteors than those in rural areas away from all light pollution. The shower is not visible from the Southern Hemisphere.
To look for meteors, experts advise taking along a blanket or lounge chair, so you can recline and avoid neck strain. Dress warmer than you think necessary if you plan to be out for more than a few minutes. Find a spot with wide-open sky. Face east but scan as much of the sky as possible. Allow 15 minutes for your eyes to adjust to the darkness.
Another half-dozen or so meteors not associated with the Lyrids could be visible in any given pre-dawn hour, from dark rural locations, according to Lunsford. These other shooting stars could appear anywhere and move in any direction.
With most digital cameras you will get a lot of static in your image. I tried doing this with my Olympus C-3030 during the 2002 Leonoids, and my pictures turned out terrible -- more static than anything else.
As far as I know film is the way to go for long exposures.
(There's actually a way to eliminate at least some of the static if you're crafty with Photoshop -- the static tends to show up on the same pixels on you camera's CCD, so if you take one fully dark photo you can use it to substract the static in subsequent pictures).
Hehe, I usually try to stay away... but RTFA!
Except the FAIW
The shower is not visible from the Southern Hemisphere
From the
The Lyrids are a northern shower, but can be observed by most mainland Australians. The best time to observe the Lyrids is in the morning between 2.00-5.00 am. However, the Lyrids low rates, combined with their closeness to the horizon, mean that few meteors are likely to be seen. To see the Lyrids, look to the north in the morning sky. About two handspans above the northern horizon is the bright, blue-white star alpha Lyra, the brightest star near the northern horizon. The Lyrid radiant is just above it and to the left by around a handspan.
Well 5-20 is on the average to higher side as far as showers tend to go, but it's also important to point out that the meteor shower numbers are frequently misleading if you're not familiar with how they're calculated.
Normally that number refers to what you'd be expected to see if you're in a completely dark sky, able to see in all directions at once, and with the radiant directly overhead. Realistically this isn't normally what happens.
Most people live near a populated area, so they only see the brighter meteors. It's also unusual to be directly underneath the radiant, so some of the meteors (up to half) may be below the local horizon. Also, you can't look in all directions. People who observe meteor showers properly often work in groups, with each person assigned a particular area of the sky to keep watch on.
There are often exceptions and perhaps you'll get lucky, but don't be too surprised or disappointed if you only see one meteor every 10 or 20 minutes, or maybe less than that. Although the article states about 5-20, Gary Kronk's meteor page comments that there can be occasional bursts of up to 100. Don't get your hopes up too much though, or you'll end up disappointed.
Set your ISO on the lowest possible setting ISO 50 or 100. Most cameras will show noticeable interference with anything larger. Note the ISO Speed number demonstrates your cameras light sensitivity.
Then take shutter speed as long as possible to desired image.
Just practice on stars and what not to get a hang of your cameras capabilities. Also, I would recommend working in your cameras uncompressed formats if the card is big enough.
So yeah, a lot of this stuff is common sense, and that is largely what photograghy is. If you are truly a noob, you'll soon here photograghy is 10% knowing what you're doing and 90% being in the right place in the right time.
actually, it's rather commonly understood that when someone says someone else is in 'a mood', that said mood is certainly not a good one. So even THAT sentence is fine, or at least understood by most.
Clear air... Go to the desert, and go high, to see the best meteor action.
Damn those pesky terrorists
Actually, while CCDs typically exhibit tremendous noise during long exposures unless attached to a hefty peltier cooler (not that they overheat, they just like to be chilly), Canon's newer, top-end-ish cameras use CMOS sensors, which most astrophotography buffs have found to be very close to noiseless. Not quite film quality yet, but getting there.
My Digital Rebel is basically noiseless regardless of exposure length at ISO 100. There are one or two variously-colored CMOS hotspots a pixel or two wide (similar to a lit pixel on an LCD screen) that begin to show themselves after a minute or two, but other than that, it's crystal clear.
Random and weird software I've written.
Although other posters point out that digital camera noise can be a problem, there are workarounds. For a start, ensure that you turn the LCD off, if possible. Try to let the camera cool down between shots.
Your camera may have a low noise setting. If not, take a long exposure photograph with the lens cap on. This "dark" frame will be noisy because of hot CCD cells. In Photoshop/whatever, subtract this image from your photograph to subtract the noise.
For best results, take several dark field images and average them.
More information and advice from Digital Camera Astrophotography
Most meteor showers have a "peak" though where the earth passes through the densest part of the comet's trail. For this meteor shower, they don't appear to know when the peak will fall. For the Leonids the last couple of years they tried to predict, and that was a certain time that would be different in different time zones.
Happy skywatching!
Take a fully dark picture and use it to subtract static? Sounds familiar.
You're re-inventing some techniques familiar to astronomers. Back when CCDs (a) were very expensive (b) were very small and (c) had to be used in dewers they were mainly seen on telescopes.
The other technique (flat-fielding) was taking a picture of a uniform light source and using that to correct the apparent brightness across your images. (My flat fields at the time were terrible, should have been even, were striped and shaded instead. Modern CCDs are prolly a lot better.)
Hold your hand out at arm's length. People with big hands generally have longer arms, so the degrees of sky covered by your hand at arm's length should be roughly the same for anyone.
evil math within Nature's Cubic Creation!
Southern hemisphere won't see anything
Really? We've got the Pi-Puppids plus a circumpolar "bright" comet, C/2001 Q4 (NEAT).
Also, the Lyrids are not the first meteor shower of the year; the first of several showers before the Lyrids are the Quadrantids. Downunder, but not left out...
Go with long exposure times and use your shutter button to hold it open. Use no less than 400 ASA, and preferrably go and pick up some of the higher stuff (800 is nice) since you only have a limited time to pick up on these beautiful objects. A neat trick is to leave your camera open the entire hour or so and let it gather multiple trails. Not to mention you can see the stars shift as well.
Good luck
"They year's first meteor shower..."
Make that "seventh":
Shower Range Peak radiant velocity population #/hour IMO
Quadrantids Jan 01-Jan 05 Jan 04 15 20 +49 41 2.1 120 QUA
delta-Cancrids Jan 01-Jan 24 Jan 17 08 40 +20 28 3.0 4 DCA
alpha-Centaurids Jan 28-Feb 21 Feb 08 14 00 -59 56 2.0 6 ACE
delta-Leonids Feb 15-Mar 10 Feb 25 11 12 +16 23 3.0 2 DLE
gamma-Normids Feb 25-Mar 22 Mar 13 16 36 -51 56 2.4 8 GNO
Virginids Jan 25-Apr 15 (Mar 24) 13 00 -04 30 3.0 5 VIR
Lyrids Apr 16-Apr 25 Apr 22 18 04 +34 49 2.1 18 LYR
"I may be synthetic, but I'm not stupid." -- Bishop 341-B