Woman dead following landslide in Assam State, India.

A woman has died following a landslide in the city of Guwahati in Assam State, India. Rini Deka Das, 35, was killed when the landslide hit her home in the Rupnagar district of the city at about 11.30 am local time on Monday 17 September 2025. The victim's husband and son are reported to have escaped from the house, but at the time of the incident she was in the bathroom, which appears to have been the part of the building directly hit by a large rock carried by the landslide. Because the house was located on a hillslope about 150-200 m above the main road, it was impossible to bring heavy machinery up to help with clearing the site, forcing rescuers to clear it by hand, as a result her body was not found until about 10.00 pm on the day of the incident, buried under more than a meter of debris.

The site of a landslide which killed a woman in Assam State, India, on 16 September 2025. Assam Tribune.

The incident is thought to have been triggered by heavy rains associated with the annual Monsoon Season. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. The Monsoon Season typically lasts from May to October each year in Assam, and frequently brings with it flooding and related events. This is a particular problem in rapidly growing cities such as Guwahati, where poorly applied planning regulations have led to housing expanding onto unstable hillslopes (often destabilised further by the removal of trees) and other high risk areas such as floodplains. 

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate. This situation is particularly intense in South Asia, due to the presence of the Himalayas. High mountain ranges tend to force winds hitting them upwards, which amplifies the South Asian Summer Monsoon, with higher winds leading to more upward air movement, thus drawing in further air from the sea.

Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

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Total lunar eclipse to be visible from Asia, Africa, Australasia, and Eastern Europe.

A total Lunar Eclipse will occur on Sunday 7 September 2025, starting at 4.27 pm GMT. It will be visible across the entirety of Australia, Indonesia, Asia apart from areas of the Russian Far East, the Indian Ocean, and the eastern half of Africa. In Eastern Europe, much of Central and West Africa, New Zealand, Melanesia, and Micronesia, part of the eclipse will be visible, although in these areas the Moon will either rise part way through the eclipse, or set before it is complete in these areas.

Areas from which the 7 September 2025 Lunar Eclipse will be visible. Dominic Ford/In the Sky.

The Moon produces no light of its own, but 'shines' with reflected light from the Sun. Thus at Full Moon the Moon is on the opposite side of the Earth to the Sun, and its illuminated side is turned towards us, but at New Moon the Moon is between the Earth and the Sun, so that its illuminated side is turned away from us.

How the phases of the Moon are caused by the relative positions of the Earth, Sun and Moon. Karl Tate/Space.com.

Lunar eclipses occur when the Moon passes through the Earth's shadow. This can only happen at Full Moon (unlike Solar Eclipses, which happen only when the Moon passes between the Earth and the Sum, and therefore only occur at New Moon), but does not happen every Lunar Month as the Sun, Moon and Earth are not in a perfect, unwavering line, but rather both the Earth and the Moon wobble slightly as they orbit their parent bodies, rising above and sinking bellow the plane of the ecliptic (the plane upon which they would all be in line every month). 

Phases of the 7 September 2025. NASA Eclipse Website.

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Over a thousand people feared dead following landslide in the Darfur Region of Sudan.

Over a thousand people are feared to have died following a landslide which hit the village of Tarseen in the Mara Mountains in the Dafur Region of Sudan on Sunday 31 August 2025. The village is reported to have been completely destroyed by the landslide, with only a single known survivor having been found by local rescue teams. A United Nations humanitarian team in Sudan estimates that the village has a permanent population of about 370 people, however the Sudan Liberation Movement/Army, a rebel group fighting for independence for Darfur which is the effective authority in the region, has claimed that as over a thousand people may have died, as about 300 families internally displaced by fighting within the region had taken shelter in the remote village.

Local rescue teams searching for survivors following a landslide which destroyed the village of Tarseen in the Darfur Region of Sudan on 31 August 2025. Sudan Liberation Movement/Army/AFP/Getty Images.

The landslide occurred following weeks of heavy rain in the region, associated with the annual wet season of southern Sudan. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. The annual wet season lasts from June to September, and with rain typically falling in a series of extended very heavy rainfall events. This makes the region extremely prone to landslides and flooding, something compounded by the country's week infrastructure and frequent civil conflicts, which make its population extremely vulnerable to such events. Such extreme weather events have become worse in recent years, driven by rising global temperatures, something which is also causing increased aridity in the drier north of the country, further fuelling internal conflicts as different populations compete for resources. 

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More than 800 dead following Magnitude 6.0 Earthquake in eastern Afghanistan.

The United States Geological Survey recorded a Magnitude 6.0 Earthquake at a depth of 8 km, roughly 27 km to the northeast of the city of Jalālābād in Nangarhar Province, eastern Afghanistan, slightly after 11.45 pm local time (slightly after 7.15 pm GMT) on Sunday 31 August 2025. The quake was felt across eastern Afghanistan and northern Pakistan, as well as in parts of northern India, and is reported to have completely destroyed several villages in Kunar Province, on the border with Pakistan. At the time of writing, more than 800 people have been confirmed to have died, with that number expected to rise significantly over the coming days. A further 2500 people are known to have been injured by the event, and the Taliban government of Afghanistan is appealing to the international community for help with rescue and reconstruction efforts.

The approximate location of the 31 August 2025 Afghanistan Earthquake. USGS.

The boundary between the Indian and Eurasian tectonic plates runs close to northern Afghanistan. The Indian Plate is moving northward relative to the Eurasian Plate, causing folding and uplift along this boundary, which has led to the formation of the Hindu Kush Mountains of Afghanistan, the Himalayas and the other mountain ranges of Central Asia., and which makes the nations in this boundary zone prone to Earthquakes.

Plate boundaries and movements beneath southern Pakistan, Iran and the Arabian Sea. University of Southampton.

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Istiorachis macarthurae: A new species of Iguanodontian Dinosaur from the Early Cretaceous Wessex Formation of the Isle of Wight.

The Iguanodontians were a highly successful group of Ornithischian Dinosaurs, which included groups such as the Dryosaurids, Iguanodonts, and Hadrosaurs. The oldest known Iguanodontian is Callovosaurus leedsi, a Dryosaurid from the Middle Jurassic Oxford Clay Formation of England, while by the End of the Cretaceous they were the most numerous group of Herbivorous Dinosaurs in Laurasia. The Iguanodontians were a relatively minor part of Late Jurassic faunas, but underwent a significant evolutionary radiation in the Early Cretaceous, becoming a numerous and morphologically diverse group, which they remained throughout the Cretaceous Period.

In a paper published in the journal Papers in Palaeontology on 21 August 2025, Jeremy Lockwood of the Fossil Reptiles, Amphibians and Birds Section at the Natural History Museum, and the School of the Environment and Life Sciences at the University of Portsmouth, David Martill, also of the School of the Environment and Life Sciences at the University of Portsmouth, and Sussanah Maidment, also of the Fossil Reptiles, Amphibians and Birds Section at the Natural History Museum, describe a new species of Iguanodontian Dinosaur from the Early Cretaceous Wessex Formation of the Isle of Wight.

The new species is named Istiorachis macarthurae, where 'Istiorachis' means 'sail-spine' in reference to the long neural spines on the vertebrae of the species, which may have given it a 'sail-backed' appearance, and 'macarthurae' honours  Dame Ellen MacArthur, an English sailor who in 2005 set a world record forthe fastest solo non-stop voyage around the world on her first attempt and who also founded the Ellen MacArthur Cancer Trust for young people on the Isle of Wight. It is described from a single, partial specimen recovered from the 1.5 m thick 'Black Band' which outcrops about 100 m to the east of Grange Chine (a chine on the Isle of White is a steep-sided gorge cut into a cliff made from a soft sediment by a stream immediately before reaching the sea). This 'Black Band' overlies the Grange Chine Sandstone within the Wessex Formation.

Locality and stratigraphy of Istiorachis macarthurae. (A) Generalised stratigraphic log and  schematic lithological logs of Wealden Group exposure between Sudmoor and Atherfield on the Isle of Wight,  showing excavation sites of the holotypes of the new Dinosaur (MIWG 6643), Brighstoneus simmondsi (MIWG 6344) and Mantellisaurus atherfieldensis (NHMUK PV R 5764). (B) Simplified geological map of the Isle of Wight. (C) Enlarged area showing the site of the excavation of MIWG 6643 in the Black Band (arrowed) (50.63354 N, 1.40654 W). Abbreviation: SS, sandstone. Note that the dashed line in (A) dividing the Wessex Formation into exposed and unexposed, applies only to the Isle of Wight exposures. Lockwood et al. (2025).

During the excavation of the specimen from which Istiorachis macarthurae is described,  MIWG 6643 was discovered and excavated by the late Nick Chase, a prolific Isle of Wight Dinosaur-hunter, who died of cancer in 2019. Unfortunately, during this excavation, the site was poached, and an unknown amount of material removed. The remaining material comprises one cervical vertebra, eight dorsal vertebrae, three dorsal rib heads, a partial sacrum, seven caudal vertebrae, both pubes and both ischia. Despite these loses, the remaining material is in good condition, with little distortion and good surface preservation.

Istiorachis macarthurae, holotype (MIWG 6643). Skeletal reconstruction. Scale bar represents 500 mm. Lockwood et al. (2025).

The most notable feature of Istiorachis macarthurae is the extremely long neural spines on its dorsal vertebrae. This is a trait which arose independently multiple times in Cretaceous Iguanodontians, although its purpose is unclear. 

Istiorachis macarthurae, holotype (MIWG 6643). 12th dorsal vertebra from early posterior series. (A)–(D), 12th dorsal vertebra in: (A) anterior; (B) left lateral; (C) posterior; (D) right lateral view. (E) reconstruction to show two consecutive vertebrae in lateral view. Abbreviations: cle, cleft; para, parapophysis; ri, ridge. Scale bar represents 50 mm. Lockwood et al. (2025).

A variety of modern Lizards have distinctive sails on their backs formed by elongation of the neural spines, but this is a feature associated with sexual selection and found only in the males. Such a role cannot be ruled out in Iguanodontians, but no evidence of sexual dimorphism has been found within the group (i.e., as far as we are aware, the males and females looked essentially the same). 

A Green Basilisk Lizard, Basiliscus plumifrons, in Alajuela Province, Costa Rica. This species has a distinctive crest, formed by elongation of the neural spines, but this trait is only seen in the males. Connor Long/Wikimedia Commons.

Large sails formed by elongated neural spines are also known from several groups of Carboniferous and Permian Tetrapods, including Sphenacodontids such as Dimetrodon limbatus and Echinerpeton intermedium, and Edaphosaurids, such as Edaphosaurus pogonias. In these Late Palaeozoic Tetrapods large sails appear to have been linked to temperature regulation. This cannot be ruled out in Iguanodontians, but where this the case crests would be expected to be a fixed trait (i.e. arising once then found in all subsequent members of the group), instead they seem to have appeared several times within different Iguanodontian lineages, with some groups having apparently gained and then lost crests.

Reconstructed skeleton of Dimetrodon incisivum from the Permian of Texas, in the collection of the Staatliches Museum für Naturkunde Karlsruhe in Germany. Such crests are thought to have been used for thermoregulation, and are a fixed trait within the Family Sphenacodontidae. Wikimedia Commons.

American Bison, Bison bison, have elongated neural spines on the forward part of their dorsal spine, which help to support the musculature needed to carry and move their large heads. Again, it is possible that the crests of Iguanodontians served a similar purpose, supporting extra musculature, but the distribution of elongated neural spines appears unrelated to size in the group, and it is unclear why this would have been present in some species, and absent in other, similar sized, species.

The skeleton of an American Bison, Bison bison, showing a crest made from elongated neural spines on the forward part of the dorsal spine. Museu de Anatomia Veterinária de Universidade de São Paulo/Wikimedia Commons.

Iguanodontians were secondarily quadrupedal grazing herbivores (that is to say, they descended from bipedal ancestors, but adopted a quadruped posture to facilitate grazing close to the ground). This required their spine be held in a horizontal position, and as they evolved to large sizes, to be able to bear large weights. To facilitate this, Iguanodontians evolved a system of ossified tendons, providing additional support for the spine, but also making it ridged and inflexible. 

Lockwood et al. speculate that elongated neural spines in Iguanodontians would have increased the efficiency of these ossified tendons, allowing for a reduction in muscle mass, which in turn would have enabled functions such as bending or running to be more efficient and less energetic. However, they are unable to explain why this would have been advantageous to some Iguanodontians but not others, and therefore the patchy distribution of the trait within the group.

Artist's impression of Istiorachis macarthurae in life. James Brown in Lockwood et al. (2025).

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