by Steve Owens | Oct 18, 2011
Originally posted on Dark Sky Diary by Steve Owens @Darkskyman
Some time in the small hours of Friday or Saturday morning (21-22 October 2011) the Orionids meteor shower will reach its peak activity rate. The peak occurs some time around 21 October each year, but this year it’s uncertain which day it will fall on.
The Orionid's parent Comet P/Halley as taken March 8, 1986 by W. Liller, Easter Island, part of the International Halley Watch (IHW) Large Scale Phenomena Network.
Meteor showers result from the Earth passing through the trail of dust and debris left behind by a comet. In the case of the Orionids the parent object is the most famous of all the comets – Halley’s Comet.
The peak meteor rate for the Orionids is lower than some of the more spectacular showers (the Perseids in August, the Geminids in December, and the Quadrantids in January all regularly outperform the Orionids) but it is still worth looking out for.
The meteors will appear to radiate from the constellation of Orion (hence the name) but they will streak across the sky in all directions, and so you shouldn’t confine yourself to only looking towards this one constellation.
On Thursday and Friday evenings the radiant rises in the east around 2200 BST (2100 UT) and continues to rise to its highest in the south just before the sky starts to brighten at 0600 BST (0500 UT). The higher the radiant above the horizon the more meteors you will see. However a crescent Moon will rises in the east on both mornings, the light from which will drown out some of the fainter meteors.
This shouldn’t matter much to you if you’re observing from an urban or suburban area, as the man-made light pollution in the sky will do a far better job of obscuring the meteor shower than the Moon will, but for lucky observers in dark sites (and I’ll be one of them, as I’m spending the weekend on Sark, the world’s first Dark Sky Island) the Moon may interfere.
Here’s a table with estimated hourly rates based on dark skies / suburban / urban areas, at hourly intervals throughout the night, assuming a ZHR =40 throughout this period (It may be that the peak will fall outwith this period, e.g. in daylight hours, so these are best-case-scenario numbers).
| Time (BST) |
Radiant
Altitude |
Radiant
Direction |
|
Hourly Rate
Urban Site |
Hourly Rate
Suburban Site |
Hourly Rate
Dark Sky Site (if Moon not present) |
| 2200 |
rises |
ENE |
|
<1 |
<1 |
<1 |
| 2300 |
8° |
ENE |
|
1 |
2 |
4 |
| 0000 |
16° |
E |
|
1 |
4 |
8 |
| 0100 |
24° |
ESE |
|
2 |
6 |
16 |
| 0200 |
33° |
ESE |
|
2 |
8 |
22 |
| 0300 |
40° |
SE |
|
2 |
9 |
26* |
| 0400 |
46° |
SSE |
|
3 |
10 |
29* |
| 0500 |
50° |
S |
|
3 |
11 |
31* |
| 0600 |
50° |
S |
|
3 |
11 |
31* |
* the true rates, given that the Moon is causing natural light pollution, are probably half these values.
All of these timings and altitudes are based on an observer in central Scotland. For other UK observers the values in columns 2-4 may be slightly off, but not noticeably so.
Observing Advice: wrap up warm, head out before midnight, sit youself in a reclining lawn chair, and enjoy the spectacle. The rates may pick up around 0200 BST on Thursday or Friday and may stay high until dawn.
by VirtualAstro | Oct 9, 2011
Originally posted on Dark Sky Diary by Steve Owens @Darkskyman on twitter
Exmoor National Park in the SW of England has just been designated an International Dark Sky Reserve, Europe’s first, by the International Dark Skies Association. This follows three years of work by park authorities, local astronomers, lighting engineers and the resident community, and is a huge achievement.
The View of the Porlock Vale from Porlock Hill looking over toward Bossington Hill and North Hill taken by Sean Hattersley on the 27/06/06
Exmoor Dark Sky Reserve follows in the footsteps of Galloway Forest Dark Sky Park, and Sark Dark Sky Island, both of which I helped to set up.
I first met Emma Dennis, the landscape officer for Exmoor National Park Authority who led the whole process, in 2008 when I brought the idea to her that Exmoor’s dark skies and favourable weather made it an ideal site for a dark sky reserve. (more…)
by VirtualAstro | Oct 7, 2011
Meteor Burst - Credit: NASA
If you live in the Europe, North Africa, and the Middle East area, then keep watching the clock for 17-18:00 UTC when you may be in the right place at the right time for a burst of activity from the annual Draconid Meteor Shower. There’s a possibility you might see up to 1,000 meteors an hour! [click to continue…]
by VirtualAstro | Oct 7, 2011
Originally posted by and full credit to Spaceweather.com
On October 8th, Earth will pass through a network of dusty filaments shed by Comet 21P/Giacobini-Zinner. Forecasters expect the encounter to produce anywhere from a few dozen to a thousand meteors per hour visible mainly over Europe, northern Africa and the Middle East. The meteors will stream from the northern constellation Draco–hence their name, the “Draconids.”
Peak rates should occur between 1600 UT and 2200 UT (noon – 6 pm EDT) as Earth grazes a series of filaments nearly intersecting our planet’s orbit. Analysts at the NASA Meteoroid Environment Office prepared this plot showing how the meteor rate is likely to vary:
If the maximum around 1900 UT reaches 1000 meteors per hour, the 2011 Draconids will be classified as a full-fledged meteor storm. The question is, will anyone see it? Bright moonlight over Europe, Africa and the Middle East will reduce the number of visible meteors 2- to 10-fold. The situation is even worse in North America where the shower occurs in broad daylight.
One way to enjoy the Draconids, no matter where you live, is to listen to them. The Air Force Space Surveillance Radar will be scanning the skies over the USA during the shower. When a Draconid passes through the radar beam–ping!–there will be an echo. Tune in to Space Weather Radio for live audio.
A similar system, still employing the radio reflection method displays meteors coming in on your computer in the form of a live graph – Meteor Live View
In Europe, an international team of scientists plans to observe the shower from airplanes flying at ~30,000 feet where the thin air reduces the impact of lunar glare. In Bishop, California, a team of high school students will launch an experimental helium balloon to higher altitudes, 100,000 feet or more, where the sky is black even at noon. Cameras in the balloon’s payload might catch some Draconid fireballs during the peak hours of the outburst.
Stay tuned for updates as Earth approaches the debris zone.
by VirtualAstro | Oct 7, 2011
Originally posted on Universe Today by meteorwatch
Credit: NASA
The Draconids are coming! Will this meteor shower produce a storm of observable meteors, or just a minor squall? The Draconid Meteor Show should begin on October 8, 2011 starting at dusk (roughly 19:00 BST) and continue through the evening. Peak activity of this normally minor and quiet shower is estimated to be at 21:00 BST (20:00 UT). There seems to be a wide range of predictions for this year’s shower, but some astronomers believe there could be up to 1,000 meteors per hour, making this a meteor storm!
(more…)
