Headlines in certain British newspapers of late would have us believe that the laws of physics and nature, the very tenets of Sir Isaac Newton’s theory of Gravity and, indeed, Kepler’s planetary laws of motion, were about to be broken in two.
Proclamations such as “Halley’s Comet returns” had astronomers all over the world scratching their collective heads – then fending off a plethora of phone calls and emails from bemused members of the general public, eager to see this once in a lifetime event some 47 years early.
Comet Halley, predicted by Sir Edmund Halley over 400 years ago, orbits the Sun every 76 years. Its last appearance in Earth's night skies was in in the mid-Eighties, meaning that it will not be with us until around 2061 – and this fact has not changed.
So What is it That Everyone's Going on About Then?
Well, Comet Halley's remnants will sort of be seen over Britain this week. The “storm” talked about is the Orionid meteor shower, which is best viewed in late October – and on Tuesday October 21st in particular. Meteor showers are largely particles shed from a comet when it makes its merry way around the solar system, leaving a trail of dust in its wake.
The Orionids, which take their name from the constellation region in the sky from which they appear to come from – and that’s just down to Earth’s position in the sky and our tilt relative to the stars at that time of year, too – are the remnants of Comet Halley's dust.
The Earth rotates the Sun every 365 (ish) days and when it intersects with these dust trails in space, they hit our atmosphere – and when I say “hit”, I mean they slam dunk in to it at anywhere up to 25,000 miles an hour or more. It’s a process similar to shooting stars or even the transportation of returning astronauts from space.
See, if you remember the heady days back when space travel was exciting – when mankind went to the actual Moon rather than threatened to maybe take some famous people into orbit at some stage soon, we promise – the astronauts would sit in a tiny conical re-entry module at the back of those giant rockets to bring them back to Earth safely.
Travelling at huge velocities, these would heat up on re-entry, slamming into the air particles that make up our atmosphere at high altitudes. The force of this friction would slow the spacecraft down but transfer all that energy in to heat, fizzling away the tiny grains of sand miles up in the sky in a matter of seconds, vaporised by the atmosphere.
So How Can I See Them?
If you want to join in the early Halley's drama, you don’t even need a telescope – just a nice comfy chair and suitable clothing to keep you warm under the hopefully clear October skies. Download the Stellarium
app (below) on PC, Mac, iOS, Android and Linux for company, too, as it will guide you around the sky a treat.
Be sure to look south towards the constellation of Orion (hence "Orionids), which is unmissable with its three stars in a line known as the "belt stars". But these meteor showers occur all through the year, too, with August's Perseids, which are dust remnants of comet Swift-Tuttle, probably the most famous non-Halley occurrence.
OK, We're Done With Eating Dust. How About Some Proper Comet Spotting?
If the current fictitious headlines have grabbed your interest in comets in general, the TV will be your best immediate bet, as the European Space Agency's Rosetta mission is landing a fridge-sized spacecraft on a comet for the first time in history in November
The ESA has been orbiting a comet known as 67P/Churyumov–Gerasimenko
for some time now and, once landed, plans to give everyone around the world some rather unprecedented views of a comet's surface in the process.
Will the Comfy Chair Still Suffice for That One?
With new comets gracing our skies all the time, the more adventurous may want to pay up for a good pair of binoculars such as the Celestron Skymasters
Or a modest refracting or reflecting telescope such as the Skywatcher ST102
if you really want to open up a whole new world of discovery…
While our new friend Comet 67P will sadly be too faint for many backyard astronomers to see, there will be plenty else to look out for. Those of a certain age will still hark back to the spectacular comet Hale-Bopp, which graced our skies in the late Nineties for several months, and was visible even from central London.
You never know, even with a small telescope, amateur astronomers are still finding new comets ahead of the professionals. And if you do, it gets your name – just ask Alan Hale or Thomas Bopp. International fame awaits! So that's spelled "G… I… Z…"
Image Credits: ESA/DLR/Osiris Camera Team, Celestron, Jason Jenkins distributed under Creative Commons licence
Nick Howes is a freelance science writer and astronomer.