Artist's concept of the universe on a 5D bubble (Image courtesy Suvendu Giri)

An article published in the journal “Physical Review Letters” describes a new model of the universe that proposes that it exists on the edge of an expanding bubble in a five-dimension space-time. A team of researchers from the Swedish University of Uppsala used string theory to hypothesize that the matter existing in the universe is accomodated at the edges of strings that extend into the fifth dimension. According to this hypothesis, what is called dark energy is an effect described by a cosmological constant in the four-dimension Friedmann equations.

GomX-4B (Image ESA–G. Porter, CC BY-SA 3.0 IGO)

ESA has announced the success of the mission of its GomX-4B nanosatellite in testing new miniaturized technologies that allow really tiny satellites to navigate in space thanks to tiny liquid butane propellers and the positioning system called star tracker to use instruments such as HyperScout, a hyperspectral camera. So far, CubeSat nanosatellites were normally devoid of propulsion systems so this one opens a new era by proving that there are cases in which a shoebox-sized satellite can do the job that until now was the prerogative of satellites hundreds of times more massive with enormously lower costs.

Great telescopes to study Comet 46P/Wirtanen

Various telescopes such as the Hubble Space Telescope, the SOFIA flying telescope and the ALMA radio telescope were used to examine the innermost region of Comet 46P/Wirtanen, nicknamed the Christmas comet because in recent days it made an Earth flyby. This expression has to be considered in a broad sense since it reached 11.6 million kilometers (more than 7 million miles) on December 16. This was enough to obtain interesting information such as the detection of hydrogen cyanide molecules in its nucleus by ALMA.

Artist's concept of a star with a violent flare (Image Casey Reed/NASA)

An article published in the journal “Monthly Notices of the Royal Astronomical Society” reports the detection of a powerful stellar flare generated by the young star cataloged as NGTS J121939.5-355557 or more simply as NGTS J1219-3555. A team of astronomers used the Next-Generation Transit Survey (NGTS) telescope array in Chile to observe a rare event that could be important for exoplanet formation in a system that is still in formation.

The Abell S1063 galaxy cluster (Image NASA, ESA, and M. Montes (University of New South Wales, Sydney, Australia))

An article published in the journal “Monthly Notices of the Royal Astronomical Society” describes a new method to detect and map the dark matter existing in galaxy clusters with a higher precision than those used so far. Mireia Montes of the University of New South Wales, Australia, and Ignacio Trujillo of the Canary Islands Institute of Astronomy, Spain, exploited the so-called intracluster light, the faint light within galaxy clusters produced by their interaction, detected in the Hubble Frontier Fields program, to map the distribution of dark matter within them.