Fireball meteor off the north coast of France.

Witnesses across much of England, Wales, Belgium, Luxembourg, and the Netherlands, as well as northern and western France and western Germany have reported observing a bright fireball slightly after 7.05 am local time (slightly after 5.05 GMT) on Monday 3 April 2023. The fireball is described as having moved from south to north, entering the atmosphere to the north of Étretat and disappearing somewhere over the English Channel. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of man-made space-junk burning up on re-entry.

The 3 April 2023 French Meteorite from Plounérin in France. Fabrice Azerty/YouTube/American Meteor Society.

Objects of this size probably enter the Earth's atmosphere several times a year, though unless they do so over populated areas they are unlikely to be noticed. They are officially described as fireballs if they produce a light brighter than the planet Venus. The brightness of a meteor is caused by friction with the Earth's atmosphere, which is typically far greater than that caused by simple falling, due to the initial trajectory of the object. Such objects typically eventually explode in an airburst called by the friction, causing them to vanish as an luminous object. However, this is not the end of the story as such explosions result in the production of a number of smaller objects, which fall to the ground under the influence of gravity (which does not cause the luminescence associated with friction-induced heating).

Heat map showing areas where sightings of the meteor were reported (warmer colours indicate more sightings), and the apparent path of the object (blue arrow). American Meteor Society.

These 'dark objects' do not continue along the path of the original bolide, but neither do they fall directly to the ground, but rather follow a course determined by the atmospheric currents (winds) through which the objects pass. Scientists are able to calculate potential trajectories for hypothetical dark objects derived from meteors using data from weather monitoring services.

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Asteroid 2023 CX1 falls to Earth over the English Channel.

Slightly before 9.20 pm local time (8.20 pm GMT) on Sunday 12 February 2023, Hungarian astronomer Krisztián Sárneczky of the Konkoly Observatory observed a Near Earth Object moving rapidly across the northern sky. He recorded this as SAR2667, and reported the finding to the International Astronomical Union's Minor Planet Centre, where the sighting was confirmed, and given the provisional designation 2023 CX1, which implies that it was the 48th asteroid (object X1 - in numbering asteroids the letters A-Z, excluding I, are assigned numbers from 1 to 25, with a number added to the end each time the alphabet is ended so that A = 1, A1 = 26, A2 = 51, etc., which means that X1 = 25 + 23 = 48) discovered in the first half of February 2023 (period 2023 C - the year being split into 24 half-months represented by the letters A-Y, with I being excluded). Later that evening the European Space Agency announced that it's scientists had calculated the asteroid was likely to impact the Earth the following day, somewhere around the French city of Rouen. 

Image of 2023 CX1 captured by the Osservatorio Astronomico Sormano in Italy slightly before midnight local time (slightly before 11.00 pm GMT) on Sunday 12 February 2023. This was one of the observations which enabled the European Space Agency to track the path of the asteroid, which was only the seventh asteroid detected before impacting the Earth, and predict the area in which it was likely to fall. Osservatorio Astronomico Sormano.

Slightly before 3.00 am GMT on Monday 13 February, witnesses across southern England and Wales, northern France, most of Belgium, the southern part of the Netherlands and western Germany reported seeing a bright fireball over the English Channel, disappearing somewhere to the north of Dieppe. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of man-made space-junk burning up on re-entry, although on this occasion the object was confirmed to be the newly discovered asteroid, 2023 CX1.

A fireball meteor caused by asteroid 2023 CX1 entering the Earth's atmosphere over the English Channel, observed from the southern Netherlands. Gijs de Reijke.

Objects of this size probably enter the Earth's atmosphere several times a year, though unless they do so over populated areas they are unlikely to be noticed. They are officially described as fireballs if they produce a light brighter than the planet Venus. The brightness of a meteor is caused by friction with the Earth's atmosphere, which is typically far greater than that caused by simple falling, due to the initial trajectory of the object. Such objects typically eventually explode in an airburst called by the friction, causing them to vanish as an luminous object. However, this is not the end of the story as such explosions result in the production of a number of smaller objects, which fall to the ground under the influence of gravity (which does not cause the luminescence associated with friction-induced heating).

Heat map showing areas where sightings of the meteor were reported (warmer colours indicate more sightings), and the apparent path of the object (blue arrow). American Meteor Society.

These 'dark objects' do not continue along the path of the original bolide, but neither do they fall directly to the ground, but rather follow a course determined by the atmospheric currents (winds) through which the objects pass. Scientists are able to calculate potential trajectories for hypothetical dark objects derived from meteors using data from weather monitoring services.

The calculated trajectory of 2023 CX1 as it fell to Earth. Simon Anghel/Institut de mécanique céleste et de calcul des éphémérides/Observatoire de Paris. 

Asteroid 2023 CX1 is calculated to have been about 233 000 km from the Earth (i.e. about 61% of the distance to the Moon) when it was discovered, and to previously have had a 799 day (2.19 year) orbital period, with an elliptical orbit tilted at an angle of 3.56° to the plain of the Solar System which took in to 0.92 AU from the Sun (92% of the distance at which the Earth orbits the Sun) and out to 2.45 AU (245% of the distance at which the Earth orbits the Sun, and more than the distance at which the planet Mars orbits the Sun). It would therefore have been classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). This means that Asteroid 2023 CX1 had occasional close encounters with the Earth, with the last having happened in June 2000.

The former orbit of asteroid 2023 CX1. JPL Small Body Database.

Asteroid 2023 CX1 is thought to have had a diameter of about a metre, and to have exploded in an airburst in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) more than 40 km above the English Channel. Nevertheless, it was calculated that the asteroid could potentially have scattered fragments on the coast of Normandy between Dieppe and Doudeville, with the potential to have produced pieces as large as 2 kg. A search was organised by the Fireball Recovery and Interplanetary Observation Network involving many volunteers and researchers, who assembled on Wednesday 15 February to scour this area. This led to the discovery of a single fragment in a field close to the town of Saint-Pierre-le-Viger, by student Loïs Leblanc. 

The single known surviving fragment of asteroid 2023 CX1, a piece of black rock weighing about 100g, found in a field near the town of Saint-Pierre-le-Viger, by student Loïs Leblanc on 15 February 2023. Fireball Recovery and Interplanetary Observation Network.

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Fireball over the English Channel.

Witnesses across the Netherlands, Belgium, Luxembourg, France, Germany, England, Wales and Scotland, have reported observing a bright fireball slightly at about 5.10 am local time GMT on Friday 12 February 2021. The fireball is described as having moved from east to west along the south coast of England, appearing off the coast of Folkstone and vanishing to the south of Brighton. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of man-made space-junk burning up on re-entry. 

 

The 12 February 2021 fireball meteor seen through dense cloud from Ash Vale in Surry, England. Meteor News.

 

Objects of this size probably enter the Earth's atmosphere several times a year, though unless they do so over populated areas they are unlikely to be noticed. They are officially described as fireballs if they produce a light brighter than the planet Venus. The brightness of a meteor is caused by friction with the Earth's atmosphere, which is typically far greater than that caused by simple falling, due to the initial trajectory of the object. Such objects typically eventually explode in an airburst called by the friction, causing them to vanish as an luminous object. However, this is not the end of the story as such explosions result in the production of a number of smaller objects, which fall to the ground under the influence of gravity (which does not cause the luminescence associated with friction-induced heating).

 

Heat map of northwest Europe showing areas where sightings of the meteor were reported (warmer colours indicate more sightings), and the apparent path of the object (blue arrow). American Meteor Society.  

 

These 'dark objects' do not continue along the path of the original bolide, but neither do they fall directly to the ground, but rather follow a course determined by the atmospheric currents (winds) through which the objects pass. Scientists are able to calculate potential trajectories for hypothetical dark objects derived from meteors using data from weather monitoring services.

 

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Dolphin found dead on beach in Dorset, southern England.

The Lulworth Coastgaurd has reported a Dolphin stranding at Durdle Door on the coast of Dorset, southern England. The animal was reported on the morning of Friday 2 January 2020, causing the Coastgaurd to investigate, as Cetacean strandings fall within their remit. Upon arrival they found the animal was a Short-beaked Common Dolphin, Delphinus delphis, a species common in waters around the UK, which had died before being discovered. The death is not regarded as suspicious, Common Dolphins are quite commonly found on beaches in Europe and other areas, simply because they are abundant. The Coastgaurds took measurements and photographed the Dolphin, data that will be shared with the Natural History Museum and the UK Cetacean Strandings Investigation Programme, who both maintain databases of Cetacean strandings around the UK.

A Short-beaked Common Dolphin found on the beach at Durdle Door in Dorset, England, on 3 January 2020. Lulworth Coastguard.

Short-beaked Common Dolphins are abundant in temperate and warm temperate waters around the world, and to some extent in the tropics. They are not considered to be endangered globally, though some populations are protected as they are considered locally vulnerable, notably those in the the North Sea, Baltic Sea, Mediterranean, Black Sea and eastern tropical Pacific, which are all protected under the terms of the Convention on the Conservation of Migratory Species of Wild Animals.

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British and French fishing fleets clash over access to Scallops on the Normandy Coast.

Clashes between British and French fishing vessels broke out last week after a group of French vessels tried to block the access of the British vessels to Scallop beds off the Normandy Coast. The French fishermen were aggrieved about British vessels targeting the Scallops outside of the fishing season, which is defined as lasting from 1 October to 15 May in France, in order to leave the Scallops unmolested during their breeding season, a convention not observed in Britain. The British vessels claim the right to access the Scallop beds as Britain is a member of the European Union, but not to be bound by French rules as the Scallops are landed in the UK.

British and French fishing vessels clash over access to Scallop beds off the Normandy Coast last week. Reuters.

In past years French fishing fleets have tolerated British Scallop trawlers in their waters out of season as long as only small vessels are involved. Smaller British fishing vessels are considered to be at a considerable disadvantage, as the UK gives the majority of its fishing quota (tightly defined in all EU countries to prevent over-fishing) to larger operators, and harvesting Scallops, which are not covered by the quota system, has been seen as a way for these smaller vessels to survive, something tolerated by the French as these vessels are thought to do little damage to Scallop stocks. However this year larger British ships have been visiting the Scallop beds, causing anger in French fishermen, who suspect that the owners of these vessels, which are likely to lose access to the area when Britain leaves the EU, are content do damage the Scallop beds in return for a quick profit.

A smaller French fishing vessel being knocked aside by a larger British ship during a dispute over access to Scallop beds off the Normandy Coast on 28 August 2018. France 3 Caen/Reuters.

After several days of clashes, and threats by the French authorities to deploy naval vessels to protect their fishing fleet, a tentative agreement has been reached between British and French politicians, with the British agreeing to withdraw their vessels as long as the French will pay compensation to the owners of these boats (it is unclear if this will actually happen). Meanwhile spokesmen for the French fishermen have made it clear that they do not blame the British trawlermen, with whom they have much in common, for the dispute, but rather British politicians for manipulating the situation.

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Magnitude 1.9 Earthquake off the coast of Devon.

The British Geological Survey recorded a Magnitude 1.9 Earthquakes off the south coast of Devon (about 40 km to the southeast of Dartmouth), slightly before 9.00 am GMT on Sunday 31 December 2017. Quakes of this size do not present any threat to human life or property, and there are no reports of this one having been felt by anybody.

The approximate location of the 31 December 2017 English Channel Earthquake. Google Maps.

Earthquakes become more common as you travel north and west in Great Britain, with the west coast of Scotland being the most quake-prone part of the island and the northwest of Wales being more prone  to quakes than the rest of Wales or most of England. However, while quakes in southern England are less frequent, they are often larger than events in the north, as tectonic pressures tend to build up for longer periods of time between events, so that when they occur more pressure is released.

The precise cause of Earthquakes in the UK can be hard to determine; the country is not close to any obvious single cause of such activity such as a plate margin, but is subject to tectonic pressures from several different sources, with most quakes probably being the result of the interplay between these forces.

Britain is being pushed to the east by the expansion of the Atlantic Ocean and to the north by the impact of Africa into Europe from the south. It is also affected by lesser areas of tectonic spreading beneath the North Sea, Rhine Valley and Bay of Biscay. Finally the country is subject to glacial rebound; until about 10 000 years ago much of the north of the country was covered by a thick layer of glacial ice (this is believed to have been thickest on the west coast of Scotland), pushing the rocks of the British lithosphere down into the underlying mantle. This ice is now gone, and the rocks are springing (slowly) back into their original position, causing the occasional Earthquake in the process.

 

 (Top) Simplified diagram showing principle of glacial rebound. Wikipedia. (Bottom) Map showing the rate of glacial rebound in various parts of the UK. Note that some parts of England and Wales show negative values, these areas are being pushed down slightly by uplift in Scotland, as the entire landmass is quite rigid and acts a bit like a see-saw. Climate North East.

Glacial rebound seems an unlikely cause of Earthquakes beneath the English Channel to the south of Cornwall, an area that was never glaciated, but this is not entirely the case. The northwest of Scotland is rising up faster than any other part of the UK, but the Earth's crust on land in the UK is fairly thick, and does not bend particularly freely, whereas the crust beneath the Channel is comparatively thin and more inclined to bend under stress. Thus uplift in Scotland can cause the entire landmass of Great Britain to pivot, causing movement in the rocks beneath the Channel.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. If you felt this quake, or were in the area but did not (which is also useful information) then you can report it to the British Geological Survey here.

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