Rocks are being thrown at us, but we haven’t noticed
Artist impression of an asteroid impact - don't worry, this doesn't happen very often... (Getty Images)
On October 7th, a small asteroid called 2008 TC3 exploded in the skies above Sudan. On October 9th, a metre-wide asteroid named 2008 TS26 buzzed Earth’s atmosphere by only 7000 km. Then on the 21st (Tuesday) a slightly bigger piece of rock called 2008 US missed us by 25,000 km. It sounds like it’s getting dangerous out there, especially when considering the last recorded object (2004 FU162) to come screaming past the Earth (at 6500 km) happened in 2004.
But don’t be concerned. Small asteroids are being thrown at us all the time; asteroid hunters are just getting better at spotting them… Continue reading →
2008 TC3 generates a huge fireball according to weather satellite Meteosat 8 (Zdenek Charvat, Czech Hydrometeorological Institute)
There may not be any ground-based imagery of the 1.1-2.1 kT fireball after asteroid 2008 TC3 hit the Earth’s upper atmosphere above Sudan, but we now have the first satellite observation of the impact. 2008 TC3 (a.k.a. “Brian” as I lovingly named it in my previous post) hit at 02:43am (UTC) yesterday morning, three minutes before the predicted re-entry. This is a huge moment for asteroid hunters: 2008 TC3 is the first ever asteroid to be discovered and accurately forecast to hit our planet.
The above image was taken by the weather satellite Meteosat 8, as Jiri Borovicka of the Czech Academy of Sciences explains: “The explosion was visible in all 12 of the satellite’s spectral channels, covering wavelengths from 0.5 to 14 microns,” he said. “The satellite takes pictures every five minutes; the fireball appeared at 0245 UTC and had faded away by 0250 UTC.”
Predicted region of atmospheric impact according to infrasound observations (Peter Brown, University of Western Ontario)
2008 TC3 wasn’t a particularly interesting asteroid. It wasn’t very big (only 1-5 metres wide) and it didn’t really stand out as being special (if it was special, we didn’t have any time to realise it anyway). If 2008 TC3 was in a crowd of other asteroids you wouldn’t have picked it out. In fact, it was that “normal” that it wasn’t named, it just kept its original asteroid designation number. 2008 TC3 was an ordinary piece of space rock in an extraordinary situation.
The last look at GOCE before it is packed away inside the rocket two half-shells (ESA)
As you probably know, I am a huge fan of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) as it is the sleekest, most aesthetically pleasing spacecraft I have ever seen. Rather than looking like a generic satellite, GOCE has been constructed in the shape of an aerodynamic spaceship as its orbit is so low that atmospheric drag will be a factor. Adding to the wow! factor is the GOCE ion engine giving a small but steady thrust to make sure GOCE doesn’t lose altitude during its Sun-synchronous orbit. Combine all these factors with the incredibly advanced science it will be carrying out during its 20 month lifetime, this is about as advanced as a terrestrial satellite can get.
So, ahead of its launch on September 10th, GOCE has been packed safely inside the Breeze-KM Upper Stage at the Plesetsk Cosmodrome in northern Russia. Next time the craft sees light will be three-minutes after launch in six days time… Continue reading →
Cryosat-2. Resembles something Da Vinci would have designed (ESA)
ESA Cryosat-2 is set for launch in 2009 and it is the second attempt at getting the technology into orbit. Back in 2005, the original CryoSat was lost after a rocket malfunction caused it to fall short of the desired orbit, but much like the Phoenix Mars Lander story (i.e. it rose from the ashes of the lost Mars Polar Lander mission, recycled spare parts and reassembled the robot), Cryosat will fly once more. So what makes this mission so important? Well, it will carry out an essential three-year survey, measuring the thickness of global ice sheets.
But why am I really mentioning it? Like many ESA missions, the designs of their satellites and robots are so cool, and Cryosat-2 is no different. From some angles it looks like a sturdy intergalactic battleship, from others it looks like it was painstakingly designed by Da Vinci. Sometimes it even looks like a flying shed. In my books, that’s one interesting satellite. The science isn’t bad either… Continue reading →
Solar panels have never looked so good. GOCE is the Porsche of orbital engineering (GOCE/ESA)
The European Space Agency is set to launch the Gravity field and steady-state Ocean Circulation Explorer (GOCE) Star Destroyer satellite on September 10th. This advanced mission will be the most sophisticated piece of kit ever to orbit the Earth, investigating the Earth’s gravitational field. It will perform a highly accurate mapping campaign, producing a high resolution reference shape of the geoid (i.e. the shape of our planet). The mission will be unprecedented, but that’s not the reason why I’m drawing attention to it…
Only last week I remarked on the coolness of the 2013 Mars rover mission in the shape of the dazzling Pasteur Rover (set to drill two-metres into Mars), and today with the announcement of the launch GOCE, it looks like ESA has done it again. They’ve encased their state-of-the-art instrumentation inside something that belongs in a science fiction movie, more reminiscent of the Imperial Star Destroyer from Star Wars than a tin box satellite… Continue reading →
The THEMIS satellites lined up inside the Earth's magnetotail. A reconnection event occurred between the 4th and 5th satellites (NASA)
Although magnetic reconnection is one of the bedrock theories within the field of space plasma physics, it has been very difficult to observe. We know that magnetic instabilities and electric currents operate within the plasma environment, but the triggering mechanism is difficult to understand. Reconnection occurs near the surface of the Sun and it occurs where the solar wind interacts with the sunward geomagnetic field. It also happens in the magnetotail (i.e. in the shadow of the Earth, where the magnetosphere is swept behind our planet by the pressure of the solar wind) and is most commonly linked with a terrestrial phenomenon: the aurora. Now, for the first time, scientists have located the point at which the magnetic field lines snap, blasting a huge amount of energy right at the Earth… Continue reading →
In the south of the UK, crop circles are a common event. These strange, flattened patterns appear suddenly and without explanation in farmland throughout the county of Wiltshire. Skeptics will argue that these patterns have been made by pranksters or by enthusiasts wanting to create large-scale crop graffiti. Others will argue it is an attempt by extraterrestrial beings to communicate with us by stamping their presence into a field. I’m keeping an open mind as to the source of these features, neither agreeing nor disagreeing with either “skeptic” or “believer”. And this is the reason why. The UK’s most complex crop circle appeared in a field earlier this month, and it took an astrophysicist to decipher what it meant… Continue reading →
Goonhilly is an area of the Lizard Peninsula in the British county of Cornwall. This region has been the destination of countless family holidays in my lifetime, and even today the Cornish landscape provides plenty of surprises for me. One landmark in particular has been the focus of my interest for as long as I can remember. Driving from the town of Helston, past RNAS Culdrose (an active Royal Naval Air Service site), and then on toward the most southerly point of mainland United Kingdom, a strange, yet familiar sight greets me. Every time I see the silhouette of those satellite dishes on the horizon of the Goonhilly Downs, I’m full of curiosity and excitement. But this year, the station is cutting back its operations to be moved to another site. The sad end of an era… Continue reading →
After some questions about the specific theories surrounding the end of the Earth in 2012, I decided to investigate the strange and mysterious “Planet X” (or “Nibiru”) in todays posting on the Universe Today. Primarily this was out of curiosity, after all, there are hundreds (if not thousands) of websites devoted to the coming of this massive planet in, you guessed it, 2012. What is it with this date? It seems that every doomsday theory has come together for a huge party in four years time. So, you can probably guess from my tone, I’m a little skeptical. To cut a long story short, I am sick and tired with seeing unfounded “scientific” (borderline psudoscientific) theories of a planet that doesn’t exist, purely to scare people into buying an aspiring best selling novel about “How to Survive the Planet X Flypast”. My argument differs quite a lot to the Planet X supporter’s argument; I back my points up with scientific evidence.