banner
You are not using a standards compliant browser. Because of this you may notice minor glitches in the rendering of this page. Please upgrade to a compliant browser for optimal viewing:
Firefox
Internet Explorer 7
Safari (Mac and PC)
Post Archive
2019 (0)2011 (6)2010 (14)
Rate This Post
Total votes: 2
Blogger Profile

Kelly Oakes GBR

I'm an Undergraduate Physics student from Imperial College London, about to start the Masters year of my degree. I mostly write about physics research papers that I find interesting in the hope that other people will find them interesting too. The wordpress version of my blog is here.

My posts are presented as opinion and commentary and do not represent the views of LabSpaces Productions, LLC, my employer, or my educational institution.

Blog RSS Feed
RSS Add to My Yahoo Add to Google
Recent Comments

Before arriving in London, each student receives a short description of the room with the possibility to share a room with a number of other independent students. Twin rooms in flat shares are idea. . .Read More
May 25, 2013, 10:42am

The one thing you forgot to mention, the most important thing as far as I'm concerned, is the possibility that dark matter does not exist at all. It could be nothing but a by-product of our means o. . .Read More
Aug 11, 2012, 11:38am
Comment by kinetic energy in Physics is hard!

agreed, the amount of hours people put into their theories is crazy, but all worth it in the end. . . .Read More
Jun 04, 2012, 12:09pm

From Poincare and caos, for modest changes in the initial conditions, the motion of the system becomes chaotic and completely unpredictable. This is impotrtant for viewing two galaxies mix. Three b. . .Read More
Aug 01, 2011, 4:08pm

Poincare find that trhee body don not have mathematical representation. The mix of two galaxies must be a big caso .Or not? . . .Read More
Jul 29, 2011, 11:14pm
Thursday, August 12, 2010

Tomorrow morning, I'll be heading away from the bright lights of London towards the not-so-bright lights of my home town in the North West of England. By complete chance, my trip away from the city coincides with a yearly event that requires a clear sky and as little light pollution as possible to be fully appreciated. Other than finding the right conditions, all you need to do to witness this event is look up.


A Perseid meteor from 8th August this year. Image: Tamas Ladanyi



The Perseid meteor shower was first observed two thousand years ago, and is visible every year from around the middle July to the end of August. At the peak of the shower, there should be 60 or so shooting stars every hour - meaning anyone looking to the sky can expect to see around one a minute, depending on location and a few other factors that can affect visibility. This year, the peak of the shower is tonight at around 0100 GMT.

The meteor shower originates from the comet Swift-Tuttle, which was discovered in 1862 and has a solid nucleus that's nearly 17 miles across. Unusually, the comet is locked into an orbital resonance with Jupiter, meaning that for every 11 times Jupiter completes an orbit of the Sun, Swift-Tuttle will go round only once. It was last seen in 1992, but we see its debris every year in the form of the Perseids.

Small particles in the comet's tail spread out along its whole orbit, forming something known as a meteoroid* stream. When the Earth passes through this stream we get a meteor shower. As the particles enter the atmosphere, they travel extremely fast (around 20km/s) causing the air in front of them to compress. The compressed air heats up, and both it and the meteor can reach temperatures of just over 1500C. At temperatures this high, the meteor doesn't last long - it burns up in the atmosphere creating shooting stars that we can see. Technically, the fast streak of light we see is called the meteor's trail, and the remnant after the trail has passed is known as the train.

All of the meteors in a shower appear to come from the same point in the sky, a spot called the radiant. This happens because all the meteors are travelling parallel to each other (the same effect causes train tracks to appear to converge in the distance). The meteors in the Perseid shower all appear to be coming from the direction of the constellation Perseus, and this is how the shower got its name.

The best time to see the Perseids, and all other meteor showers, is in the last few hours before the Sun comes up in the morning. As the Earth rotates, the side turning towards the Sun is able to catch more meteoroids, upping the number of meteors in the sky.

This year astronomers are expecting a more spectacular light show than usual. The peak of the shower is coming only two days after a new moon, so there will only be a little moonlight around to spoil the view. Even in urban areas the number of meteors visible per hour could reach between 10 and 20.

Wherever you are, don't forget to look up.



* Before entering our atmosphere, the particles are known as meteoroids. When they're travelling through the atmosphere they are meteors, and if one managed to make it to the ground intact it would be called a meteorite (a Perseid meteor is very unlikely to reach Earth, as the biggest ones are only around the size of a pea).


For details on how best to see the Perseids where you are, take a look here and here.


Post title stolen from Patrick Wolf.


This post has been viewed: 402 time(s)

Blog Comments

Evie
Rate Post:

Like 0 Dislike
It's so cloudy out.. I hope I get to see at least something cool tonight..

BTW, thanks for posting this! I was gonna do a short reminder, but you beat me to it :) Annnd you have way more details.

Kelly Oakes
Rate Post:

Like 0 Dislike
Just had a look out and I don't think I've got much of a chance here in London, but I'm hoping there'll still be a few when I'm back home tomorrow - it's a lot more rural there!
Add Comment?
Comments are closed 2 weeks after initial post.
Friends