2026 ED138: A new candidate Dwarf Planet in the Kuiper Belt.

In the late twentieth century, our model of the Solar System was relatively simple, with nine planets orbiting the Sun, some of which had moons and rings, plus a variety of smaller comets and asteroids. The smallest of these planets, Pluto, was somewhat of an oddity, being smaller several of the Solar System's moons, including our own, and having a highly eccentric orbit which crossed the orbit of another planet, Neptune, but was clearly still to large a be a comet or asteroid. However, in the early twenty first century, this model began to change, with the discovery of a series of Pluto-like bodies beyond Neptune starting with Quaoar in 2002, then Sedna in 2003, Orcus and Haumea in 2004, and Eris and Makemake in 2005. This led the International Astronomical Union to reconsider how bodies within the Solar System are classified, coming up with a new category of objects, 'dwarf planets', in 2006. 

Dwarf planets are defined as objects large enough to have become rounded under the influence of their own gravity, but not large enough to have cleared their orbital path of other objects. Pluto was reclassified as a dwarf planet, losing its status as the Solar System's smallest planet, as was Ceres, the largest body in the Main Asteroid Belt, along with the newly discovered bodies Quaoar, Sedna, Orcus, Haumea, Eris, and Makemake. This list has subsequently grown with the addition of bodies such as Salacia and Gonggong.

In a press release issued on 27 October 2026, the Vera C. Ruben Observatory, which is located on Cerro Pachón in Chile, announced the discovery of a new candidate dwarf planet, 2026 ED138, which was discovered by astronomer Matthew Holman of Harvard University, who was analysing data collected by the Ruben Observatory, looking for moving objects in the outer Solar System.

Holman found 30 observations of the new object made by the Ruben Observatory between 4 March and 11 July 2026, which provided him with enough data to discover additional sightings in imagery from the Dark Energy Camera on the the Víctor M. Blanco 4-meter Telescope at the Cerro Tololo Inter-American Observatory, and the Asteroid Institute’s ADAM Precovery service, with the oldest images dating back to 1937. 

A mosaic of images captured by NSF–DOE Vera C. Rubin Observatory of the newly discovered dwarf planet candidate 2026 ED138. 2026 ED138 was discovered in observational data from Rubin spanning 4 March–11 July 2026. It was found by Rubin Operations team member and in-Kind contributor Matthew Holman, who contributes to improving Rubin's algorithms that search for distant moving objects in our Solar System. Its distance from the Sun places it beyond the orbit of Pluto, and initial analysis indicates that it may be among the largest and brightest bodies scientists have discovered in this region of the Solar System. Vera C. Rubin Observatory/NOIRLab/SLAC National Accelerator Laboratory/AURA Image Processing/Mario Jurić/Davide de Martin/Mahdi Zamani.

The designation 2026 ED138 implies that it was the 2454th asteroid (object D138 - in numbering asteroids the letters A-Y, 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 D138 implies the (138 x 25 + 4) 2454th asteroid) discovered in the first half of March 2026 (period 2026 E - the year being split into 24 half-months represented by the letters A-Y, with I being excluded).

2026 ED138 is currently about 47.225 AU from the Sun (where 1 AU is the average distance between the Earth and the Sun), with an orbital period estimated at 281 years, which will bring it as close as 36.86 AU from the Sun and as far as 49.04 AU. As an object which has an orbit entirely outside the orbit of Neptune, it is a trans-Neptunian Object, and having a low-eccentricity (approximately circular) orbit, it is a Classical trans-Neptunian Object. This orbit is tilted at 24.5° to the plain of the Solar System, making 2026 ED138 a Hot Classical trans-Neptunian Object; a Classical trans-Neptunian Object with an orbit tilted at more than 5° to the plain of the Solar System. Such objects are thought to have been disturbed from the plain of the Solar System by gravitational interactions with the planet Neptune.

The relative positions of 2026 ED138, the Earth, and the planets of the Outer Solar System on Sunday 1 November 2026. JPL Small Body Database.

2026 ED138 is a bright object, with an absolute magnitude estimated to be between 2.85 and 3.19. This would make it the ninth or tenth brightest trans-Neptunian Object discovered to date. From this brightness it is estimated that it has a diameter of between 600 and 1500 km. This variation stems from an uncertainty as to whether it has a bright surface, which would place it at the lower end of this range, or a dull one, which would place it towards the upper end, and make it a Dwarf Planet. Potential observations of the object with infrared telescopes, observations of stellar occulations (events in which it passes in front of a star), and possibly direct observations with the James Webb Space Telescope could tell us more about its nature.

The orbital period of 2026 ED138 suggests that it is locked into a 12⁄7 orbital resonance with Neptune. This is roughly the same as that of the dwarf planet Haumea, as well as a group of objects called the Haumean Family of trans-Neptunian Objects. However, it is not currently thought to be a member of that family due to the difference in its albedo (brightness) to that of Haumea and the Haumean Family objects.

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At least eighteen dead following Magnitude 7.0 Earthquake beneath Baqên County, Tibet.

The China Earthquake Networks Center recorded a Magnitude 7.0 Earthquake at a depth of 10 km beneath Baqên County in northeast Tibet, close to Mount Everest and the border with Tibet slightly before 10.35 pm local time (slightly before 2.35 pm GMT) on Thursday 22 October 2026. At least eighteen people have died as a result of this event, with seventy six people known to have been injured, eleven of them seriously. The Earthquake is known to have caused the collapse of at least 339 houses, however, the nature of the area, with an average altitude of 4800 m above sealevel, and many people living in scattered villages in steep-sided valleys, where temperatures regularly fall below 0°C at night, means that these figures may worsen. There have been a number of aftershocks in the region, leading local authorities to evacuate 12 000 people from their homes. 

Villagers in a temporary resettlement camp following a Magnitude 7.0 Earthquake in Baqên County, Tibet, on 22 October 2026. Tenzin Nyida/Xinhua.

Earthquake activity in the area is caused by the uplift of the Tibetan Plateau, due to the impact of India into Eurasia to the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. The collision of the Indian and Eurasian plates has led to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

Much of Tibet and neighbouring areas of Central Asia and the Himalayas, are prone to Earthquakes caused by the impact of the Indian Plate into Eurasia from the south. When two tectonic plates collide in this way and one or both are oceanic then one will be subducted beneath the other (if one of the plates is continental then the other will be subducted), but if both plates are continental then subduction will not fully occur, but instead the plates will crumple, leading to folding and uplift (and quite a lot of Earthquakes). 

The movement of India into Eurasia over the last 71 million years. United States Geological Survey.

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Norellraptor barsboldi: A new species of Microraptorine Dinosaur from the Early Cretaceous Jehol Biota of northeastern China.

The Microraptines are a small group of Paravian Dinosaurs (the group that includes Birds and their closest relatives, the Dromaeosaurs, Troodontids, and Scansoriopterygids), known mostly from the Early Cretaceous Jehol Biota of northeastern China. The remarkable preservation of the Jehol Biota fossils means that while the Microraptines were not apparently widespread or numerous, the specimens we do have are often exceptionally well preserved. Such fossils have produced Microraptines with feather-like integumentary structures, true pennaceous feathers and remnants of the gut contents, enabling a more detailed reconstruction of their ecology than has been possible for many more numerous Dinosaur groups.

Many Microraptines are interpreted as having been capable of flying, and the close relationship between Microraptines and Birds has made them an important group to palaeontologists studying the origin of flight. The closest sister group to the Microraptines is usually thought to be the Dromaeosaurs, a group of medium-sized Paravian Theropods clearly quite incapable of flight, which raises two possibilities. Either the ability to fly arose twice (or more than twice) within the Paravian clade, or the earliest members of the group had the ability, with groups such as the Dromaeosaurs losing this ability secondarily. 

In a paper published in the journal Nature Communications on 29 September 2026, Xuri Wang of the Key Laboratory of Stratigraphy and Paleontology of the Ministry of Natural Resources, and the Hebei GEO University, Yannan Ji of the Chinese Academy of Geological Sciences, Andrea Cau of the OPHIS Museo Paleontologico e Centro Erpetologico, Martin Kundrát of the Center for Integrative Paleobiology at Pavol Jozef Šafárik University, Yichuan Liu, also of the Key Laboratory of Stratigraphy and Paleontology of the Ministry of Natural Resources, and of the China University of Geosciences, Yang Wang, again of the Key Laboratory of Stratigraphy and Paleontology of the Ministry of Natural Resources, and Qiang Ji, also of the Hebei GEO University describe a new species of Microraptorine Dinosaur from the Early Cretaceous Jehol Biota of northeastern China.

The new species is named Norellraptor barsboldi, where 'Norellraptor' means 'Norell's Raptor' in honour of American palaeontologist Mark Allen Norell, and 'barsboldi' honours the late Mongolian palaeontologist Rinchen Barsbold (1957-2025), these being two scientists who have made exceptional contributions to the study of Paravian Dinosaurs. It is described from a single specimen (130108-MHGU-F4281) from an exposure of the Jiufotang Formation in the town of Lamadong, in Jianchang County, which is in western Liaoning Province.

Norellraptor barsboldi 130108-MHGU-F4281. (a) Whole specimen. (b) Skull in lateral view. (c) Close up of the rostrum. (d) Close up of the posterior part of skull. (e) Pectoral region. (f) Distal end of tail. Abbreviations: aof, antorbital fossa; arm, ascending ramus of maxilla; at, anterior tympanic recess; bt, basal tuber; bp, basypterygoid process; cf, coracoid fenestra; ct, caudal tympanic recess; cnV, 5th cranial nerve opening; cnVII, 7th cranial nerve opening; cv, cervical vertebra; d1, first dorsal vertebra; de, dentary; dt, dorsal tympanic recess; fo, foramen; fr, frontal; fu, furcula; gl, glenoid; h, humerus; la, lacrimal; lat, laterosphenoid; lcv, last caudal vertebra; lp, lateral pneumatic recess; mc, metacarpus; mxf, maxillary fenestra; na, nasal; oc, oto￾sphenoid crest; or, otic region; pa, parietal; paw, postantral wall; pmx, premaxilla; pp, paroccipital process; ppd, posterior processes of dentary; pt, pterygoid; pxf, promaxillary fenestra; r, radius; rp, retroarticular process; sa, surangular; sc, sca￾pula; so, supraoccipital; sp, sternal plate; sr, sclerotic ring; u, ulna; up, uncinate process; vor, ventral otic recess. Arrow indicates point of histological sampling. Scale bars are 50 mm (a); and 10 mm (b)–(f). Wang et al. (2026).

Norellraptor barsboldi has a skull triangular in lateral view, with an elongated snout, a vaulted area between the eyes, and very enlarged fenestra (skull openings). Its teeth are differentiated, with the premaxilary teeth being small and unserrated, while the maxilary teeth are larger, particularly so towards the back of the mouth, serrated, and hooked. Preserved plumage can be seen close to the right humerus and the synsacrum, ventral to the proximal caudal vertebrae, attached to the distal caudal vertebrae, ventral to the right tibiotarsus, and lateral to the right tarsometatarsus. However, the preservation of this is poor, preventing a detailed assessment of its structure.

Plumage of Norellraptor barsboldi (130108-MHGU-F4281). (a) whole specimen. (b) Distal tips of primary feathers. (c) Tibial plumage. (d) Distal tip of metatarsal feathers. (e) Plumage adjacent to humerus and thorax. (f) Plumage adjacent to ilium and tail base. (g) Distal tail feathers. Scale bars are 10 mm. Wang et al. (2026).

An osteological sample was taken from the distal portion of the mid-diaphysis of the left radius of specimen 130108-MHGU-F4281, and serial sectioned to give a view of its bone-structure. This section of bone had been crushed post-mortem, due to the weight of overlaying sediment. The bone is less than half a millimetre in diameter, and has a large medullary cavity lacking any internal structures, suggesting that the bone was heavily pneumatized in life. This is surrounded by a layer of laminated endosteal bone, making up 8-15% of the total bone thickness, then a thicker layer of periosteal bone, split into three layers by two lines of arrested growth (such lines typically form as an animal grows, with slowed growth in a season with less favourable conditions, such as winter or a dry season). This might be taken to mean the living Microraptor had lived at least two years after hatching. However, the large size of the inner cavity probably implies some total reabsorption of bone as the Dinosaur grew, making it several years older.

Histology of the left radius of 130108-MHGU-F4281. (a)–(c) Close-up of the left radius midshaft microstructure (d), (e). Physical transversal sections in transmitted (a), (d) fluorescent (b) and elliptically polarised light (c), (e). In (a)–(c) note an irregular interface between the inner periosteal bone and the endosteal bone (red arrow); a high difference in fluorescence between well-developed primary osteons of the zone 1 and of the inner group of osteons of the zone 2 (blue arrow); and ill￾developed primary of the outer group of osteons of the zone 2 (yellow arrow); a low fluorescence in the secondary osteonal bone (orange arrow). Compare the higher birefringence of the endosteal bone, an annulus-like tissue (white arrow), and early bone deposited to form zone 3 (black arrow). In (d), (e) note the occurrence of more organised osteocyte lacunae in the outer region of zone 1 and throughout the zone 2; increased birefringence in primary osteons of zone 1 (green arrow); in an annulus associate with Layer of Arrested Growth 1 (white arrow) and zone 3 (yellow arrow); and highly birefringent endosteal bone tissue (orange arrow). Abbreviations: ?ans, putative annulus; avbl, avascular layer; avr, avascular region; END, endosteal bone; FLB, fibro-lamellar bone; ICL, inner circumferential line; LAG, line of arrested growth; LAG-nvc, LAG crossing neurovascular canal; LAG1, inner circumferential layer; LAG2, outer line of arrested growth; ipos, ill developed primary osteon; lanvc, laminar neurovascular canal; lonvc, longitudinal neurovascular canal; meca, medullary cavity; onvc, neurovascular canal open on outer surface; osla, osteocyte lacuna; PER, periosteal bone; PFBM, parallel-fibered bone matrix; pos, primary osteon; pnvc, primary neurovascular canal; prpos, partially resorbed primary osteon; prsos, partially resorbed secondary osteon; ranvc, radial neurovascular canal; rel, resorption line; rupt, postfossilization rupture; snvc, secondary vascular canal; sos, secondary osteon; z1-3, first through third zone. Scale bars are 200 microns (a)-(c) and 100 microns (d), (e). Wang et al. (2026).

Norellraptor barsboldi shares many features with early Birds, but this appears to be a case of convergent evolution, with a phylogenetic reconstruction recovering it as a highly derived Microraptorine, and the Microraptors as the earliest branching group within the Paraves, i.e. the most distantly related group to the Birds within that larger group. This phylogeny shows the Microraptorines progressively acquiring 'Bird-like' traits over their history, apparently in response to similar evolutionary stimuli, something which Wang et al. interpret as evidence for the independent evolution of flight.

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Dwarf Planet 136199 Eris approaches opposition.

The dwarf planet 136199 Eris will reach opposition (i.e. be directly opposite the Sun seen from Earth) on Sunday 18 October 2026 at 6.32 pm GMT. This means that it will both be at its closest to the Earth this year, about 94.47 AU (94.47 times the average distance between the Earth and the Sun, or about 14, 133 000 000 km), and completely illuminated by the Sun. While it is not visible to the naked eye observer, the planets have phases just like those of the Moon; being further from the Sun than the Earth, 136199 Eris is 'full' when directly opposite the Sun. 

The orbit and position of 136199 Eris and selected Solar System planets at 7.00 pm GMT on Sunday 18 October 2026. JPL Small Body Database Browser.

Although this coincides with a First Quarter Moon, the prospects for viewing without a very powerful telescope are not as good. The dwarf planet will be in the constellation of Cetus and will be at its highest point in the sky at about midnight local time, from anywhere on Earth (this is because the rising and setting of objects in the sky is caused by the Earth's rotation, not the movement of the object). (Even at it's very brightest 136199 Eris will only have a Magnitude of 18.6, making it almost impossible to see with any but the largest of Earth-based telescopes, and where resolvable it will only be possible to see it as a point of light indistinguishable from a faint star.

136199 Eris orbits the Sun on an eccentric orbit tilted at an angle of 44.1° to the plane of the Solar System, which takes it from 35.9 AU from the Sun (35.9 times the average distance at which the Earth orbits the Sun) to 97.5 AU from the Sun (97.5 times the average distance at which the Earth orbits the Sun. With an average distance of 67.74 AU, 136199 Eris completes one orbit around the Sun every 558 years. This means that the planet is almost stationary compared to the faster moving Earth, so that it reaches Opposition only four days later each year than the year before, and reaches Solar Conjunction (when it is directly on the opposite side of the Sun to the Earth), roughly six months later.

136199 Eris was discovered on 5 January 2005 by a team led by Mike Brown of the Palomar Observatory in California. With a diameter of 2326 km it is considered to be the second largest dwarf planet in the Solar System (after 134340 Pluto) as well as the sixteenth largest body in the Solar System, excluding the Sun (though several moons, including our own, are larger). It is also the largest body in the Solar System never to have been visited by a spacecraft (again, with the exception of the Sun). 136199 Eris has a single moon, Dysnomia, which has a diameter of about 700 km and obits at a distance of about 37 350 km.

Labelled Hubble Space Telescope Image of 136199 Eris, showing its satellite Dysnomia. Captured on 12 June 2007. Mike Brown/NASA/European Space Agency/Wikimedia Commons.

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Trachoma eliminated in Timor-Leste.

The elimination of Trachoma, a transmissible Bacterial disease which is thew world's leading infectious cause of blindness, in Timor-Leste (East Timor) has been confirmed by the World Health Organization, according to a press release issued on 3 September 2026. This conformation also marks the elimination of Trachoma across the Southeast Asia Region, with all other countries in that region either having previously eliminated the disease or never having suffered from it. The conformation is therefore a significant step on the way to the World Health Organization's goal of eliminating the disease worldwide by 2030.

The flag of Timor-Leste. Isabel Nolasco/Wikimedia Commons.

The announcement is the result of a campaign of screening which began on Atauro Island in 2015, and which has been rolled out to every region of the country. In 2025, a total of 4949 children aged 0-5 in all 13 municipalities of Timor-Leste did not find a single case of Trachoma, leading to the conclusion that the disease had been eliminated. The country does, however, plan to continue to monitor for Trachoma, and retain the ability to treat the disease.

Trachoma is caused by the Bacterium Chlamydia trachomatis, and spread through contact with mucus emitted from the eyes and nose during infection, and can be spread by Flies. Infections are most common among children, and the disease can spread rapidly in overcrowded environments, particularly where sanitation is poor and access to clean water is limited. The Bacterium infects the inside of the eyelid, causing a roughening which can in turn lead to damage to the surface of the eye. Eventually the disease can lead to the eyelids turning inwards, blinding the patient. Infections are generally fought off fairly quickly, particularly in adults, but having been infected does not offer protection against future infections, and the damage caused by each infection is cumulative. Chlamydia trachomatis is vulnerable to the antibiotics azithromycin and tetracycline.

McCoy cell monolayer micrograph reveals a number of intracellular Chlamydia trachomatis inclusion bodies; Magnified 200 times. The intracellular inclusion body represents the replication phase of the Chlamydia spp. organisms, whereupon, the reorganised reticulate body multiplies through binary fission into 100-500 new reticulate bodies, which mature into elementary bodies. Eugene Arum/Norman Jacobs/Centers for Disease Control and Prevention/Wikimedia Commons.

Timor-Leste is the 33rd country to eliminate Trachoma as a public health risk, with the other countries being Algeria, Australia, Benin, Burundi, Cambodia, China, Egypt, El Salvador, Fiji, The Gambia, Ghana, India, Iraq, Iran, Laos, Libya, Malawi, Mali, Mauritania, Mexico, Morocco, Myanmar, Nepal, Oman, Pakistan, Papua New Guinea, Saudi Arabia, Senegal, Togo, Tunisia, Vanuatu and Vietnam. Trachoma is one of twenty Neglected Tropical Diseases identified by the World Health Organization's Road Map for Neglected Tropical Diseases 2021–2030, with 68 countries now having eliminated at least one of these diseases. 

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