Category Astronomy/Space

Even though Earth’s magnetic field shields us from solar wind and space weather, it doesn’t always offer complete protection. Researchers have discovered a new mechanism in Earth’s space environment that can allow solar particles to slip through the planet’s first line of defense.

The constant interaction between Earth’s magnetic field and the sun’s supersonic particles sometimes results in small-scale plasma jets that can weaken the barrier’s protection against space weather effects, which not only produce glorious aurorae, but can also cause disruption of power grids and satellite communicatio...

The subject of this image is a group of three galaxies, collectively known as NGC 7764A. They were imaged by the NASA/ESA Hubble Space Telescope, using both its Advanced Camera for Surveys and Wide Field Camera 3. The two galaxies in the upper right of the image appear to be interacting with one another. The long trails of stars and gas extending from them give the impression that they have both just been struck at great speed, thrown into disarray by the bowling-ball-shaped galaxy to the lower left of the image.

In reality, interactions between galaxies happen over very long time periods, and galaxies rarely collide head-on with one another...

A research team led by Dr. Prabhakar Tiwari from the National Astronomical Observatories of Chinese Academy of Sciences (NAOC) has found that superhorizon modes could explain the observed Hubble tension.

Their findings were published in The Astrophysical Journal Letters on Jan. 18.

It is generally believed that the universe is isotropic and homogeneous on large distance scales. This hypothesis forms the basis of the standard Big Bang cosmology, called the cosmological principle (CP)...

Researchers at The University of Manchester have succeeded in observing the so-called Schwinger effect, an elusive process that normally occurs only in cosmic events. By applying high currents through specially designed graphene-based devices, the team — based at the National Graphene Institute — succeeded in producing particle-antiparticle pairs from a vacuum.

A vacuum is assumed to be completely empty space, without any matter or elementary particles. However, it was predicted by Nobel laureate Julian Schwinger 70 years ago that intense electric or magnetic fields can break down the vacuum and spontaneously create elementary particles.

This requires truly cosmic-strength fields such as those around magnetars or created transitorily during high-e...