Saturday 31 August 2019

Adenomera phonotriccus: A new species of Nest-building Frog from Pará State, Brazil.

The Leptodactylidae are a group of Frogs found throughout Central and South America and the Caribbean,  which are sometimes known as 'Nesting Frogs' from the habit of some species of constructing nests of foam, often away from water (though always in damp environments) in which to incubate their young. There are currently eighteen recognised species of Adenomera, all found in South America to the east of the Andes, although the genus is known to contain a number of cryptic species (species that closely resemble other species, and cannot be separated by simple, non-invasive examination). The presence of cryptic species can have a profound influence on conservation efforts, as ‘species’ thought to be wide ranging with large populations and broad environmental tolerances can turn out to be complexes of closely related but reproductively isolated species, each with a smaller population and distribution, and narrower range of environmental tolerances.

In a paper published in the American Museum Novitates on 7 February 2019, Thiago de Carvalho of the Departamento de Zoologia e Centro de Aquicultura at the Universidade Estadual Paulista, Ariovaldo Giaretta of the Laboratório de Taxonomia e Sistemática de Anuros Neotropicais at the Universidade Federal de Uberlândia, Ariadne Anguelo of the International Union for the Conservation of Nature's Amphibian Specialist Group, Célio Haddad also of the Departamento de Zoologia e Centro de Aquicultura at the Universidade Estadual Paulista, and Pedro Peloso of the Instituto de Ciências Biológicas at the Universidade Federal do Pará, and the Division of Vertebrate Zoology at the American Museum of Natural History, describe a new species of Adenomera from Pará State in Brazil.

The new species is named Adenomera phonotriccus, where 'phonotriccus' means 'voice of a small Bird' in reference to the mating call of the male Frogs, which sounds like call of a Tody-tyrant of the Neotropical genus Hemitriccus. The species is described from four adult male Frogs collected from the western margin of the lower Araguaia River in the municipality of Palestina do Pará. These are small in size, measuring 19.8–21.6 mm in length, and robust, with a mottled brown colouration, sometimes with red stripes, and a white underside.

Live specimens (all adult males) of Adenomera phonotriccus from the type locality (Palestina do Pará, state of Pará, northern Brazil). (A) Holotype (MPEG 41155). (B) Paratopotype CFBH 43130. (C)‒(D) Paratopotype CFBH 43131. De Carvalho et al. (2019).

The new species is known from only a single location on a forest edge in an area of active deforestation, due to conversion of large areas where the species occur into pasture and agricultural land, though it is unclear how widely distributed the species is, and therefore what it's conservation status is.

See also...
Follow Sciency Thoughts on Facebook.

Asteroid 2019 QU3 passes the Earth.

Asteroid 2019 QU3 passed by the Earth at a distance of about 670 000 km (1.74 times the average  0distance between the Earth and the Moon, or 0.45% of the distance between the Earth and the Sun), at about 1.40 pm GMT on Saturday 24 August 2019. There was no danger of the asteroid hitting us, though were it to do so it would not have presented a significant threat. 2019 QU3 has an estimated equivalent diameter of 3-11 m (i.e. it is estimated that a spherical object with the same volume would be 3-11 m 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) in the atmosphere more than 30 km above the ground, with only fragmentary material reaching the Earth's surface.

 The calculated orbit of 2019 QU3. JPL Small Body Database.

2019 QU3 was discovered on 27 August 2019 (three days after its closest approach to the Earth)  by the University of Hawaii's PANSTARRS telescope. The designation 2019 QU3 implies that it was the 92nd asteroid (asteroid U3 - in numbering asteroids the letters A-Y, excluding I, are assigned numbers from 1 to 24, with a number added to the end each time the alphabet is ended, so that A = 1, A1 = 25, A2 = 49, etc., which means that U3 = 20 + (24 X 3) = 92) discovered in the second half of August 2019 (period 2019 Q).
2019 QU3 has a 927 day orbital period and an eccentric orbit tilted at an angle of 0.74° to the plane of the Solar System, which takes it from 1.01 AU from the Sun (i.e. 101% of he average distance at which the Earth orbits the Sun) to 2.71 AU from the Sun (i.e. 271% of the average distance at which the Earth orbits the Sun, and considerably outside the orbit of the planet Mars). It is therefore classed as an Amor Group Asteroid (an asteroid which comes close to the Earth, but which is never closer to the Sun than the Earth is). This means that 2019 QU3 has occasional close encounters with the planet Earth, with the last having occurred in June 2014.
See also...
Follow Sciency Thoughts on Facebook.

Friday 30 August 2019

Miner killed in accident in Pennsylvania.

A miner has died in an accident at the Enlow Fork Mine in Washington County, Pennsylvania. Tanner Lee McFarland, 25, was killed when part of a long wall collapsed on him at about 6.00 pm local time on Thursday 29 August 2019, at the Consul Energy-owned coal mine, part of the Pennsylvania Mining Complex. The cause of the accident is being investigated.

Miners at the Enlow Fork Wine in Pennsylvania. GKVisual.

Long wall mining is a highly mechanised form of deep pit mining, in which the coal seem is accessed along a straight line (the 'long wall') by cutting equipment connected to a conveyor belt. The coalface is intentionally caused to collapse by the cutting equipment, causing the coal to fall into hoppers mounted on the conveyor, which is then removed from the mine. Miners do not usually come between the conveyor and the coal face while the system is running, as much due to the dangerous nature of the cutting equipment as the risks presented by the face itself.

Cutting equipment at the coalface of a long wall mine in Pennsylvania. Consul Energy.

See also...
Follow Sciency Thoughts on Facebook.

Eruption on Mount Stromboli.

The Italian National Institute of Geophysics and Volcanology reported a significant eruption on Mount Stromboli, a volcanic island off the east coast of southern Italy, to the north of Sicily, on Wednesday 28 August 2019, the second large event on the island this summer. The volcano produced a plume of ash and several streams of lava which flowed down the flanks of the volcano, reaching the sea. Nobody was hurt by this event, but several tourists were forced to flee beaches in the paths of the lava and a number of small fires were started.

An eruption on Mount Stromboli, Italy, on Wednesday 28 August 2019. ANSA/AP.

Stromboli has been in more-or-less constant eruption since at least Roman times, and is thought to be about 5000 years old, though it is not generally considered dangerous if not approached closely; there are three settlements on the island, all less than three kilometres from the summit. Stromboli is noted for frequent small explosive eruptions, which through lava bombs, ash and incandescent rock fragments out of the crater, a type of eruption known by vulcanologists around the world as 'strombolian'. The summit rises 924 m above sea level.
 The approximate location of Mount Stromboli. Google Maps.
Southeastern Italy lies on the edge of the Eurasian Plate, close to its margin with Africa. The African Plate is being subducted beneath Italy on along a margin that cuts through the island of Sicily. The African plate is being subducted beneath Italy, and as it sinks is melted by the friction and heat of the Earth's interior. Some of the melted material then rises through the overlying plate fuelling the volcanoes of southern Italy.
 Map showing the tectonic plates underlying Italy and southern Europe, and the location of the l'Aquila Earthquake. Napoli Unplugged.
See also...
Follow Sciency Thoughts on Facebook.

Thursday 29 August 2019

Magnitude 1.4 Earthquake in Cheshire, England.

The British Geological Survey recorded a Magnitude 1.4 Earthquake at a depth of about 6 km, about 1 km to the east of the village of Bridgemere in Cheshire, England, slightly after 1.00 am British Summertime (slightly after midnight GMT) on Tuesday 27 August 2019). There are no reports of any damage or injuries associated with this event, and nor would they be expected from such a small event, though it is possible it was felt locally.

 The approximate location of the 27 August 2019 Cheshire 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.

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. 

See also...
Follow Sciency Thoughts on Facebook.