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Planet found in the “neptunian desert” of a star

An international group of astronomers has identified a rogue planet orbiting its star in the so-called “Neptunian desert.” The Neptunian desert is a region close to the stars where large planets with their Neptune-like atmospheres are not expected to survive, as the strong radiation from the star would cause the evaporation of any gaseous atmosphere, leaving behind only a rocky core.

However, NGTS-4b, nicknamed the “Forbidden Planet,” still has its atmosphere intact and is the first exoplanet of its kind to be found in the Neptunian desert. The results are reported in Monthly Notices of the Royal Astronomical Society.

NGTS-4b is smaller than Neptune and three times larger than Earth. It is dense and warm, with a mass equal to 20 times that of the Earth and an average surface temperature of 1000 degrees Celsius. The planet orbits its star closely, completing a complete orbit in just 1.3 days.

The planet was identified using the Next-Generation Transit Survey (NGTS) observation facility at the Paranal Observatory of the Southern European Observatory in the Atacama Desert in Chile. NGTS is a collaboration between the universities of Warwick, Leicester, Cambridge and Queen’s University of Belfast, together with the Observatoire de Genève, the DLR Berlin and the Universidad de Chile.

When looking for new planets, astronomers use structures such as NGTS to look for a flexion of the light of a star, which occurs when an orbiting planet passes in front of it, blocking part of the light. Usually, these decreases are 1% and more can be detected by ground-based research, but NGTS telescopes can record a drop of just 0.2%.

This sensitivity means that astronomers can now detect a wider range of exoplanets: those with a diameter between two and eight times that of the Earth, between the smallest rocky planets and gas giants.

“This is a very rare planet, and it is the first time that a small planet has been detected by a large field Earth telescope,” said co-author Ed Gillen of the Cavendish Laboratory in Cambridge, who conducted the data analysis to determine the mass, radius and orbit of NGTS-4b.

Researchers believe that the planet may have moved into the Neptunian desert recently, in the last million years, or that it has been very large and the atmosphere is still evaporating.

“This planet must be resilient – it’s precisely in the area where we expected that the Neptune planets would not survive,” reports Chief Richard West of Warwick University. “It’s really amazing that we found a planet passing through a star that oscillates less than 0.2% – this has never been done before by telescopes on the ground, and it was great to find it after working on this project for a year.”

“We’re now looking for our data for other similar planets to help us figure out how dry this Neptunian desert is or whether it’s greener than we once thought,” said Gillen.

The research was supported in part by the Science and Technology Facilities Council of the United Kingdom.

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Nordic microalgae cleans wastewater and produces biodiesel

A further study, written by the researcher of the University of Umeå Lorenza Ferro, highlights the importance of microalgae in the environment and the considerable possibilities that these plants offer in the field of biofuel production.

Biomass made of algae has been increasingly taken into account and used in recent years for the production of biofuels because these microorganisms can form and store large amounts of lipids. The latter can then be converted into biodiesel. As if that were not enough, the same microalgae can be very useful for purifying wastewater because the nitrogen and phosphorus in them can also be used to feed the microalgae.

In the Nordic countries of Europe, however, the use of microalgae is very limited: this environment is in fact characterized by very long winters with the sun peeping out much less often than in the regions further south and this causes significant problems in the use of microalgae. The researcher shows, in her study, that in such contexts using native strains of Nordic microalgae can be the solution.

“My work has shown that local Nordic microalgae are much better than standard varieties. Our Nordic strains are currently tested under “real conditions” with the aim of extending the growth period until late autumn or even winter,” says the researcher.

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Genetic mutation has evolved in humans to cope with sugar consumption

Human evolution is of course still ongoing and a discovery has been made about a limited genetic variant that is affecting humans in relation to today’s diet. Research, published in eLife, shows how human bodies are starting to change in relation to the management of blood sugar levels. This evolutionary process has been determined by the change in diets in the last hundreds of years due to the increase in the consumption of sugary foods and carbohydrates in general.

Initially, researchers were only studying the CLTCL1 gene, a gene that is involved in the production of the protein CHC22 which plays a key role in the regulation of a glucose transporter in human fat and muscle cells. This transporter is released by hormonal insulin, which in turn reacts to higher blood glucose levels. Researchers analyzed the genomes of 2,504 people in the Global Genomes Project and those of 61 other species and realized that the gene that produces CHC22 has changed during the recent human evolutionary history.

Nearly half of the people surveyed possessed a variant of CHC22 produced by a mutated gene that became more common in recent human history as communities developed more complex ways of cooking food and agriculture. Researchers also analyzed the genomes of ancient populations and found that this variant was more present in more agricultural populations than in those that were more concerned with hunting or the random collection of food to survive. All these things suggest that the increase in carbohydrate consumption was the selective force that guided this genetic adaptation.

Does this mean that in the future, a fairly distant future in any case, humans may have defeated diabetes genetically and without external intervention? According to the researchers, further research is needed to understand how this newly discovered genetic variant can affect our physiology in the future, but what is certain is that the changes that occurred a few thousand years ago regarding our eating habits have strongly shaped, and are still doing, our evolution.

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VLT photographs double asteroid passing near the Earth at 70,000 mph

Using the SPHERE tool of the Very Large Telescope (VLT), a group of researchers from the European Southern Observatory obtained relatively sharp images of 1999 KW4, a double asteroid that approached the Earth recently. The results obtained show that even the VLT can be used in the context of the study of Near-Earth Objects (NEO) and in general in the identification of any dangerous objects approaching the Earth.

In addition, the feat is to be emphasized considering that the double asteroid was speeding at a speed of 70,000 miles per hour, a speed that probably would have made it impossible to take an image with any other terrestrial instrument. Moreover, this double asteroid is very similar to another system of two asteroids called Didymos and Didymoon, which in the future could in fact pose a threat to Earth so much so that NASA is planning to plan a mission to try to correct its orbit.

The researchers studied and photographed 1999 KW4, a double asteroid composed of a larger and a smaller body, which approached Earth at a minimum distance of 5.22 million miles this year. It is a binary asteroid with a total diameter of 1.3 miles, discovered as early as 1999, whose orbit is well known and which could not have posed any danger to our planet.

The researchers used SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch), a particular tool capable of capturing direct images of space bodies very often far away (the researchers are trying to use it to capture direct images of exoplanets) thanks to an advanced adaptive optics system able to correct the turbulence of the Earth’s atmosphere and to provide sharp images like those of space telescopes.