Police station and residential buildings evacuated after giant sinkhole opens in Bangkok, Thailand.

Several residential buildings as well as the Samsen Metropolitan Police Station remain closed after a sinkhole approximately 30 m wide and more than 15 m deep opened up beneath the Samsen Road in the Dusit District of Bangkok, Thailand, on Wednesday 24 September 2024. The nearby  Vachira Hospital has been able to remain open, benefiting from a system of deep piles intended to keep it stable during Earthquakes. The sinkhole swallowed a number of vehicles, as well as several electricity pylons, but nobody was injured during the incident.

A massive sinkhole which opened up in Bangkok, Thailand, on 24 September 2025. Chalinee Thirasupa/Reuters.

Sinkholes are generally caused by water eroding soft limestone or unconsolidated deposits from beneath, causing a hole that works its way upwards and eventually opening spectacularly at the surface. Where there are unconsolidated deposits at the surface they can infill from the sides, apparently swallowing objects at the surface, including people, without trace. 

Bangkok is known to be prone to such problems, being situated on a flat plain of alluvial sediments, and having historically suffered from widespread subsidence due to over-extraction of water from underlying aquifers. This incident was initially linked to heavy rainfall in the area, linked to the local rainy season, which peaks in September. However, subsequent investigations have suggested that vibrations from tunnel excavations for a new subway system may have led to the breakage of a water main, causing water to gush into, and erode, the soft sediments beneath the Samsen Road.

Water gushing from a broken water main into a newly opened sinkhole on 24 September 2025. Thailand Construction News.

Soil liquefied by the initial water main break flowed into the under-creation Purple Line Tunnel, creating a void which undermined further water mains, causing them to sag and break, releasing more water and causing the rate of erosion to increase, leading to the dramatic emergence of the sinkhole at about 7.00 am on 24 September. 

This situation was made worse by initial attempts to fix the problem, which involved pouring 700 cubic meters (about 1500 tonnes) of liquid concrete into the hole. This concrete also found the gap into the tunnel system, with its additional mass causing a 30 m² breach into the tunnel system to open up, through which the concrete flowed into the tunnel.

Engineers must now wait for the concrete to set before clearing out and stabilising the breach, then filling in whole, whilst at the same time preventing water from the seasonal rains entering the hole. Initial concerns that the newly constructed Samsen Metropolitan Police Station would need to be demolished have now been dispelled, but engineers are warning that it may be over a year before it is possible for it to reopen. 

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Ceres comes to opposition.

Dwarf Planet 1 Ceres will reach opposition (the point at which it is directly opposite the Sun when observed from the Earth) at 1.12 pm GMT on Thursday 2 October 2025, when it will also be at the closest point on its orbit to the Earth, at a distance of 1.96 AU (i.e. 1.96 times as far from the Earth as the Sun, or about 239 361 000 km), and be completely illuminated by the Sun. While it is not obvious to the naked eye observer, asteroids have phases just like those of the Moon; being further from the Sun than the Earth, 1 Ceres is 'full' when directly opposite the Sun. As 1 Ceres is only about 939.4 km in diameter, it will not be visible to the naked eye, but with a maximum Apparent Magnitude (luminosity) of 7.6 at opposition, it should be visible in the Constellation of Cetus to viewers equipped with a good pair of binoculars or small telescope, with the best visibility being at about midnight local time from anywhere on Earth.

The calculated orbit and position of 1 Ceres at 1.00 pm GMT on Thursday 2 October 2025.  JPL Small Body Database. 

Because Ceres is further from the Sun than the Earth, its orbital period is much longer than ours, with the Dwarf Planet completing one obit every 1683 days (4.65 years), on an eccentric orbit tilted at 10.6° to the plane of the Solar System. The orbit of Ceres places it within the inner part of the Main Asteroid Belt, but due to its large size, with a diameter of 939.4 km, it is considered to be a Dwarf Planet rather than an asteroid.

High resolution image of Ceres made on 20 September 2020, by the Dawn Space Probe. Wikimedia Commons/NASA/JPL/Caltech.

Ceres was discovered on 1 January 1801 by Giuseppe Piazzi, a Catholic priest at the Academy of Palermo, Sicily. It was the first body to be discovered in the Main Asteroid Belt, and at the time when it was discovered an international search was underway for a presumed 'missing planet' between the orbits of Mars and Jupiter (although Piazzi was studying stars when he first observed Ceres, and initially presumed he had found a new comet). Ceres was for a long time considered to be the largest asteroid in the Solar System, but in 2006 was re-classified as a Dwarf Planet, as part of a revision of the classification of Solar System bodies driven by the discovery of a growing number of bodies in the Outer Solar System which are too large to be considered asteroids or comets yet to small to be considered to be planets. 

Of the ten bodies currently classified as Dwarf Planets, only Ceres is located within the Main Asteroid Belt, with five lying in the Kuiper Belt (Orcus, Pluto, Salacea, Haumea, Quaoar, and Makemake), two lie within the Scattered Disk (Gonggong and Eris), and one within the Detached Region on the outer fringe of the Solar System (Sedna).

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Magnitude 6.9 Earthquake to the east of Cebu Island, the Philippines.

The Philippine Institute of Volcanology and Seismology recorded a Magnitude 6.9 Earthquake at a depth of 5 km, off the east coast of the northern part of Cebu Island, Philippines, slightly before 10.00 pm local time (slightly before 2.00 pm GMT) on Tuesday 30 September 2025. The event  was felt across the central Philippines, but no tsunami warning was issued, and no damage or casualties have been reported at the time of writing, although it is possible that unreported damage or injuries have occurred in remote locations. The Philippine Institute of Volcanology and Seismology is warning of a high possibility of significant aftershocks. 

The approximate location of the 30 September 2025 Cebu Earthquake. USGS.

The geology of the central Philippines is Complex. The west of Mindanao Island is located on the Banda (or Sunda) Microplate, and the east on the Philippine Plate, which is being subducted beneath the Sunda (or Banda) Microplate along the central part of the island. Immediately to the east of the Island the Pacific Plate is being subducted along the Philippine Trench, and passes beneath eastern Mindanao as it sinks into the Earth. This is not a smooth process, an the plates constantly stick together then break apart again as the pressure builds up, resulting in Earthquakes.

Subduction beneath the Philippines. Yves Descatoire/Singapore Earth Observatory.

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Bright fireball over California caused by space junk.

Witnesses across much of California and parts of Nevada have reported observing a bright fireball meteor at about 7.50 pm local time (about 12.50 pm GMT) on Thursday 25 September 2025. The fireball is described as having moved from southwest to northeast, appearing near Lake Berryessa and disappearing to the east of Waldo Junction. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. 

The 25 September 2025 California fireball meteor observed from Galt. Jesse Smith/American Meteor Society.

Such 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, which appears to have been the case on 25 September. The Aerospace Corporation, a nonprofit organisation which (amongst other things) monitors space traffic, has calculated that the fireball was caused by the breakup of Starlink satellite 1711, one of a cluster of Starlink satellites which was due to re-enter the atmosphere on that day. The satellite would have re-entered the atmosphere at a speed of about 8000 metres per second, compared to an average of 30 000 m per second for meteorites, leading to a slower and brighter burning object.

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Petalidium saxatile: A new species of Petal-bush from Namibia.

Petal-bushes, Petalidium spp., are woody perinal shrubs in the Family Acanthaceae found in arid sandy or stoney areas of Africa, India, and the Mascarene Islands, although most species are found in areas of Southern Africa with summer rainfall and no frosts. There are currently 35 species recognised from Southern Africa, of which 33 are found in Namibia, 13 in Angola, and six in South Africa. Despite the name 'bush', they are diverse in form, ranging from scrambling herbs to large, robust shrubs. Many species of Petalidium are fast-growing and produce attractive  flowers, leading to some species being cultivated by gardeners.

In a paper published in the journal Phytotaxa on 3 September 2025, Wessel Swanepoel of the H.G.W.J. Schweickerdt Herbarium at the University of Pretoria, Kyle Dexter of the School of GeoSciences at the University of Edinburgh, the Royal Botanic Garden Edinburgh, and the Department of Life Sciences and Systems Biology at the University of Turin, Martino Adamo, also of the Department of Life Sciences and Systems Biology at the University of Turin, Erin Manzitto-Tripp of the Department of Ecology & Evolutionary Biology, & Museum of Natural History at the University of Colorado, and Abraham Van Wyk, also of the H.G.W.J. Schweickerdt Herbarium at the University of Pretoria, and of the South African National Biodiversity Institute, describe a new species of Petalidium from the Kaokoveld Desert of northwestern Namibia.

The new species is described on the basis of four populations of Petalidium in the Kaokoveld discovered by Wessel Swanepoel while carrying out research for a monograph on the genus in Southern Africa. The populations had been observed by him before, and assumed to belong to the species Petalidium canescens, which is also found in the region. However, in May 2018 Swanepoel visited a population near Palmwag while it was in flower, suggesting that it was a different species, something which was later backed up by generic analysis.

The new species is named Petalidium saxatile, where 'saxatile' derives from the Latin 'saxatilis', meaning 'found amongst rocks', from the habitat where it lives. These Plants form a hemispherical woody shrub about 50 cm tall, with bifurcating stems and elongate oval leaves, both covered with white hairs. Flowers are roughly tubular, with four lobes, the lower of which is yellow and the others pinkish brown (unlike the all pink flowers of Petalidium canescens).

Petalidium saxatile, morphology of flowers. (A), (B) Newly opened and faded flowers. Anterior corolla lobe inside (adaxially)  bright yellow and without nectar guides. (C) Flower viewed from above, showing puberulous abaxial surface of posterior corolla lobes. (D) Flowers viewed obliquely from above, all corolla lobes discolorous with the outside (abaxial) surfaces puberulous and notably paler in  colour. The long white trichomes next to the flower on the right do not belong to the plant, but is a wind-blown feathery awn (arrowed) of  a member of the Grass genus Stipagrostis. Wessel Swanepoel in Swanepoel et al. (2025).

Petalidium saxatile is known from only four sites, three in an approximate line from Palmwag southwards to Bergsig, and one on Welbedacht Farm, to the south of Khorixas. It has been found growing among rocks from the Etendeka Group basalt, on arid hillsides and along drainage lines at elevations of 860–1130 m above sealevel, between 70 and 150 km from the sea. Searches of other areas with similar conditions did not reveal any further populations. It is calculated that the area of potential habitation for Petalidium saxatile is 3337 km², but the area of actual habitation is less than 20 km². All of the areas where the species is found are prone to prolonged droughts. As such, Swanepoel et al. recommend that Petalidium saxatile be classified as Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. 

Known distribution of Petalidium saxatile (black dots). Swanepoel et al. (2025).

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Spicomellus afer: A surprisingly well-armoured Ankylosaur from the Middle Jurassic of Morocco.

The Ankylosaurs were a group of heavily-armoured, short-limbed, wide-bodied, Ornithischian Dinosaurs, best known from Late Cretaceous deposits in Eurasia and North America. Although the group is known to have existed by the Middle Jurassic, remains from this period are limited to a jawbone and a few teeth from two sites in England, and it has been speculated that earlier members of the group may have lacked the heavy armour of the Late Cretaceous species. This is not unreasonable, the Late Cretaceous saw the emergence of a range of new predators, including novel groups of Theropod Dinosaurs and Crocodilians, and the first large predatory Mammals and Snakes, leading to the evolution of novel defence strategies in many herbivorous groups. 

Although well known from the Laurasian Continents, Ankylosaurs were for a long time thought to be absent from Gondwana. However, in 1986 this was changed by the discovery of Antarctopelta oliveroi, from the Late Cretaceous of Antarctica, the first known Dinosaur from that continent. This was followed in 1989 by the discovery of Kunbarrasaurus ieversi, a small Ankylosaur from the Early Cretaceous of Australia. The subsequent discovery of Stegouros elengassen from the Late Cretaceous of southern Chile and Patagopelta cristata from the Late Cretaceous of Argentina confirmed that Ankylosaurs were present, if uncommon, across Gondwana in the Cretaceous, and it was speculated that these Dinosaurs were members of a single clade, the Parankylosauria, which had split from its Laurasian cousins early in the history of the group, and developed a range of distinctive traits, including a distinctive tail weapon formed from five pairs of robust osteoderms, fused together to form a flat, fan-like weapon called a 'macuahuitl', in reference to a traditional weapon from Mesoamerica, made from a series of obsidian blades mounted on a wooden club, giving a sword-like appearance. 

Spicomellus afer was first described in 2021 from a single rib-fragment with fused spikes from Morocco. The fossil appeared to have clear Ankylosaurian affinities, and, importantly, came from the Middle Jurassic, apparently confirming the hypothesis of an early-branching clade of Ankylosaurs reaching Gondwana and diversifying there.

In a paper published in the journal Nature on 27 August 2025, Susannah Maidment of the Fossil Reptiles, Amphibians and Birds Section a the Natural History Museum, and the School of Geography, Earth and Environmental Sciences at the University of Birmingham, Driss Ouarhache, Kawtar Ech-charay, Ahmed Oussou, Khadija Boumir, and Abdessalam El Khanchou of the GERA Laboratory at Sidi Mohamed Ben Abdellah University, Alison Park of Emanya Fossil Preparation and Conservation, Luke Meade, also of the School of Geography, Earth and Environmental Sciences at the University of Birmingham, Cary Woodruff of the Phillip and Patricia Frost Museum of Science, and the Museum of the Rockies, Simon Wills and Mike Smith, also of the Fossil Reptiles, Amphibians and Birds Section a the Natural History Museum, Paul Barrett, again of the Fossil Reptiles, Amphibians and Birds Section a the Natural History Museum, and of the Evolutionary Studies Institute at the University of the Witwatersrand, and Richard Butler, once again of the School of Geography, Earth and Environmental Sciences at the University of Birmingham, describe a new partial skeleton of Spicomellus afer, enabling a more complete reconstruction of the species and a re-interpretation of the history of the Ankylosauria. 

The new material comprises a left quadrate, two cervical, two dorsal, four sacral and four free caudal vertebrae, two handle vertebrae, six dorsal ribs with spikes fused to their dorsal surfaces, both scapulocoracoids, ilia and pubes, the right ischium, two metatarsals, an elaborate cervical half ring bearing extremely long spikes, a sacral shield bearing small and large spikes, numerous plates, large and small spikes of various morphologies, and several compound osteoderms comprising combinations of small and large spikes. These suggest an unusually well-armoured Animal, even compared to other Ankylosaurs, casting doubt upon the prevailing idea that heavy armour developed in the group in the Late Cretaceous as a result of increased predation pressures. 

A life reconstruction of Spicomellus afer. (a), (b) A life reconstruction of Spicomellus afer  showing hypothetical positions of armour in dorsal (a) and right lateral (b)  views. (c) USMBA 19: a blade-like spine that is 43 cm long. (d) USMBA 70:  a compound osteoderm with large, oval base. The long spike is 35 cm long. (e) USMBA 12: part of the left ilium bearing a fused sacral shield, which includes  a large iliac spike lying dorsal to the acetabulum. The height of the spike, as  preserved, is 24 cm. (f) USMBA 14: cervical half-ring. The length of the longest spike is 87 cm. (g) USMBA 30: a slender, rounded spike that is 10 cm long. (h) USMBA 12: a portion of the left ilium bearing a fused sacral shield ornamented by small, rounded spikes. (i) USMBA 37: a slender, rounded spike that is 30 cm long. (j) USMBA 12: a large spike with a robust, expanded base plate. The spike is 23 cm long. The specimen was found in association with the iliac spike (e). (k) USMBA 26: a plate, probably from the pectoral region based on comparisons  with other Ankylosaurs. The plate is 24 cm in length. (l) USMBA 25: a compound osteoderm with spikes, one of which is broken. The better-preserved spike appears to have been the more slender of the two and is 34.5 cm long. (m) USMBA 17: a blade-like spine with an expanded base that is 27 cm long. (n) USMBA 63: a three-spiked osteoderm with a broken basal plate. The height of the middle spike is 3.5 cm. Matt Dempsey in Maidment et al. (2025).

The deposits from which the skeleton was recovered come from the Bathonian stage, making them between 168.2 and 165.3 million years old, making Spicomellus afer equal in age to the oldest known Ankylosaur fossils, a scattering of isolated from the Bathonian White Limestone of England, and close to the predicted split between the Ankylosauria and the Stegosauria. 

A phylogenetic analysis carried out by Maidment et al. was unable to recover the Parankylosauria as a distinct clade of Gondwanan Ankylosaurs. The Chilean Stegouros elengassen was found to be the sister species to all other Anylosaurs, apparently representing an early-diverging, and otherwise lost, lineage, while other members of the proposed Parankylosauria were scattered throughout the Ankylosauria as a whole, with their formerly apparent similarities being a result of convergent evolution.

A simplified time-calibrated strict reduced consensus tree showing  the putative phylogenetic position of Spicomellus afer. Note that the timescale for the  Middle Jurassic has been expanded so that branching patterns can be clearly  seen. Taxa in grey are from the Northern Hemisphere; those in black are from the  Southern Hemisphere. Green text denotes clades. Abbreviations: Aal, Aalenian; Alb, Albian; Apt, Aptian;  Baj, Bajocian; Barr, Barremian; Bath, Bathonian; Berr, Berriasian; Call, Callovian;  Cam, Campanian; Cen, Cenomanian; Con, Coniacian; Haut, Hauterivian;  Hett, Hettangian; Kimm, Kimmeridgian; Maas, Maastrichtian; Oxf, Oxfordian;  Plien, Pliensbachian; Sant, Santonian; Sine, Sinemurian; Tith, Tithonian;  Toar, Toarcian; Tur, Turonian; Vala, Valanginian. Maidment et al. (2025).

Based upon this, Maidment et al. conclude that heavy and extensive armour first appeared in Ankylosaurs in the Middle Jurassic, and was apparently a defining feature of the group from the outset. The further speculate that this may have been a result of sexual selection rather than predation pressure, something which could drive the rapid development of an anatomy distinct from that of their closest relatives. Under this scenario, the widespread appearance of heavily armoured Ankylosaurs in the Late Cretaceous might represent not the adaptation of a less well armoured group to a high predation environment, but rather the advantageous pre-adaptation of the group to such an environment, enabling the Ankylosaurs to flourish at the expense of less well-armoured rival groups.

Armour of Spicomellus afer. Richard Butler, Kawtar Ech-charay, Ahmed Oussou and Alison Park for scale (and the scale bar on the table is 8 cm long). Maidment et al. (2025).

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