You know it’s a good night when a beautiful alignment of planets is the second best thing that’s going to happen.
Thursday, August 12th, is such a night.
The show begins at sundown when Venus, Saturn, Mars and the crescent Moon pop out of the western twilight in tight conjunction. All four heavenly objects will fit within a circle about 10 degrees in diameter, beaming together through the dusky colors of sunset. No telescope is required to enjoy this naked-eye event: sky map.
The planets will hang together in the western sky until 10 pm or so. When they leave, following the sun below the horizon, you should stay, because that is when the Perseid meteor shower begins. From 10 pm until dawn, meteors will flit across the starry sky in a display that’s even more exciting than a planetary get-together.
The Perseid meteor shower is caused by debris from Comet Swift-Tuttle. Every 133 years the huge comet swings through the inner solar system and leaves behind a trail of dust and gravel. When Earth passes through the debris, specks of comet-stuff hit the atmosphere at 140,000 mph and disintegrate in flashes of light. These meteors are called Perseids because they fly out of the constellation Perseus.
Swift-Tuttle’s debris zone is so wide, Earth spends weeks inside it. Indeed, we are in the outskirts now, and sky watchers are already reporting a trickle of late-night Perseids. The trickle could turn into a torrent between August 11th and 13th when Earth passes through the heart of the debris trail.
2010 is a good year for Perseids because the Moon won’t be up during the midnight-to-dawn hours of greatest activity. Lunar glare can wipe out a good meteor shower, but that won’t be the case this time.
As Perseus rises and the night deepens, meteor rates will increase. For sheer numbers, the best time to look is during the darkest hours before dawn on Friday morning, Aug. 13th, when most observers will see dozens of Perseids per hour.
For best results, get away from city lights. The darkness of the countryside multiplies the visible meteor rate 3- to 10-fold. A good dark sky will even improve the planetary alignment, allowing faint Mars and Saturn to make their full contribution to the display. Many families plan camping trips to coincide with the Perseids. The Milky Way arching over a mountain campground provides the perfect backdrop for a meteor shower.
Enjoy the show!
Author: Dr. Tony Phillips | Credit: Science@NASA
Well worth seeing the Perseids. The wife and i sat out on the swing seat a couple of years ago……
Magical.
The Perseids weren’t bad either…….
I like the “Possibly related posts: (automatically generated)”
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Seeing the Pleides rising always says “Autumn’s coming” to me!
I’m going to try to stay awake until dark to see the show – it sounds great!
Alas! All of this is Northern Hemisphere. How much is visible in Southern Australia?
Here is the astronomy picture of the day from a few years ago:
http://antwrp.gsfc.nasa.gov/apod/image/0708/perseids_bruenjes_big.jpg
I try to look out for the Perseids every year. Unfortunately every year for the last 6 years it has been cloudy and I have missed them! I have my fingers crossed this time for an unspoilt view.
We are expecting the usual response – numerous 999 calls to the Maritime Rescue Coordination Centre reporting distress flares.
Happens every year.
Kohl Piersen says:
August 11, 2010 at 2:44 am
Kohl.
The constellation of Perseus rises in the north easters sky at about 3Am local time in Perth. I reckon if you look to the north any time after say 10PM you’ll see some Perseids passing upwards maybe to the zenith if you are lucky. You should be able to see them all the way through the wee hours.
I used to watch them from my home in rural Scotland when I was younger. Beautiful clear nights away from any light pollution.
I’m now on an oil rig in the South China Sea – too many bright lights on the rig here I’m afraid.
Ken Hall says:
August 11, 2010 at 2:57 am
Snap! 🙂
But the Triffids ! !
Thanks for the reminder. It seems the past few years have been cloudy. Will set out lounge chairs with sleeping bags and spend the night out if it’s clear. Had a marvelous shower one year, dozing through the night with constant streams and flashes of light.
Every 133 years the huge comet swings through the inner solar system and leaves behind a trail of dust and gravel.
Why does it leave a trail of dust and gravel? Does the earth leave a trail of dust and gravel? I don’t think so. Is it because comets are largely made of ice, and this tends to melt the nearer they get to the sun? But even if the ice melted, wouldn’t the water be travelling at the same velocity as the comet? There must be explosions taking place on comets if dust and gravel is being thrown off.
well, Jimmy (and Kohl) – its pissing it down here in Perth tonight – first rain in aaaages too – so no Perseids for us 🙁
Nice post. Probably the best way to watch meteors is to lie in a reclining garden chair. Wrap up warm (unless you live in Kentucky or somewhere like that) and allow about 20 minutes for your eyes to adjust to the darkness – that way you’ll see more. There’s usually other things going on in the night sky too – planes, satellites, maybe birds and Chinese lanterns. Watch out for noctilucent clouds low down on the Northern horizon when it’s nearly dark – they’re rare but this is the sort of time of the year you might see them. Enjoy! 🙂
A w/e in Brittany with clear skies hopefully. Thanks for a nice post.
Icarus, we’re trying to beat the heat here in Central Kentucky (mid 90’s F and high humidity). I was laying in the pool early Monday morning (1:00am) and spotted 4 Perseids within 5 minutes. One was quite bright. I would recommend this this viewing strategy to anyone. It eliminates the stiff neck the following morning. I’m looking forward to 8/12 – 13 when they are expected to increase in number.
John
If Friday night is the night, must reduce beverage intake.
idlex,
The Earth is quite massive compared to comets. Even a vocanic explosion here doesn’t send debris into orbit or beyond. What goes up comes back down because of gravity.
A comet is not so massive, so it wouldn’t take much of an impact or explostion to lose material out into space. But there is something else about comets related to their orbits.
Comets have elliptic orbits, but they are very “eccentric”. When they are farthest away from the Sun, the solar radiation is so tiny that it is cold enough for even gases to freeze. Another thing about eccentric orbits is that when an object is farther away from the sun they move slower and when they come in close they swing by faster. So comets spend most of their time in the freezing deep space, where frozen particles settle to their surfaces. When they swing closer to the sun, the solar radiation warms them up, gases thaw and jet out. This gives them a “coma”, a hazyness that obscures the hard part in the center. This coma is pushed away by solar wind. This is why comets have “tails”. This also ejects the gravel and dust from the comet, which gives us pretty meteor showers.
Put your camera on a solid mount and point it at the north star. Use your B setting to leave the shutter open for as long as your camera will allow before you get overexposure from sky glow/ light pollution in your area. Set the camera for its widest angle and slowest F-stop. You will get star trails circling the pole star and, if lucky, some of the meteor trails as well. Works well with digital cameras in rural areas with little sky glow as you can check your exposures to see how long you can keep the shutter open before you wash out or start to get artifacts from heat etc.
Thanks. I hadn’t thought of frozen gases.
Got the lawn chair(recliner) ready and 55 lb. Springer in case it is cooler than normal.
Springer snores, however….
If you live in the USA, Canada, or certain parts of Mexico check out the Clear Sky Chart
http://cleardarksky.com/csk/
“It’s the astronomers forecast. It shows at a glance when, in the next 48 hours, we might expect clear and dark skies for one specific observing site.”
I saw more Perseids than I expected Saturday night at a dark sky site in the New Hampshire mountains. I’m not sure if it were more than normal, but if so that suggests the peak should be impressive. Also several “sporadic” meteors not associated with a meteor shower, or at least not the Perseids.
See http://www.skyandtelescope.com/about/pressreleases/100141169.html for more information. See http://www.skyandtelescope.com/observing/home/99304684.html for more technical information.
idlex says:
August 11, 2010 at 6:22 am
> Why does it leave a trail of dust and gravel?
Tommy answered the why, this is the what. Visually, check out comet photos with a tail or two,
http://www2.jpl.nasa.gov/comet/images.html has a “few” of Hale-Bopp. http://www2.jpl.nasa.gov/comet/gif/yen34.jpg is a nice one.
The blue tail is composed of gas that is swept away by the solar wind and ionized by sunlight. The other tail is dust, and is less affected by the solar wind. The dust is what would be a meteor shower some day if Earth ever went through it. (Unlikely to impossible.)
Handy NASA Flux Estimator. Make sure you choose the Perseids shower, location, date, etc. It seems to populate somewhat randomly on startup.
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.
International Meteor Organization (IMO) http://www.imo.net/node/1295
Clear Skies!
The Perseid Meteors http://www.oarval.org/perseids.htm
Blasted California coastal marine layer! It will be a miracle if we can see any celestial objects after sundown. Foggiest year in recent memory. I do like watching planets too. . .
After a week of clear skies, predictions are for thickening clouds for the next 48 hrs. Never fails – when the skies are clear, the moon is too bright – when the moon is new, the clouds pour in. Grr.
John Michalski: Floating in the pool sounds like a great way to watch meteors! 🙂
In the northwest GA (US) mountainous pine forests the snugly-wrapped blanket is needed to add weight in the cot or lawn chair. (Makes the body inside the blanket too heavy for the mosquitoes to carry off …)
I don’t know, but this concrete is killing me. I sure hope I can see it so I can tell my great grandchildren one day I saw it with my one only. Oh and I saw my first shooting star!!
I saw quite a few last night…they were beautiful. I was wrapped up very thoroughly to withstand the cold on this night in High Summer in England (SW) but still had to retreat just after 1am as I was getting too cold. Lying on the concrete steps isn’t the best, but our loungers are defunct!
I also saw a few satellites (maybe one was a very high flying aircraft).
It brought back memories of lying on a dam wall in Victoria in Australia to see what was supposed to be a huge shower of meteors a few years ago. There weren’t many but there was one coloured stunner. We were frozen then too, but at least it was meant to be winter at the time!
Watched them the last two nights sitting on a dock on a lake in Maine, it was spectacular with an impressive backdrop of the Milky Way. It was in the 50s so the mosquitoes weren’t a problem either. 😉
We sat outside last night on a perfectly clear night until 4:00am and only saw 2 meteors. I guess we have way too much light pollution down here in S. Fla. Bummer and tired!