Is there a second Earth out there in space? Our knowledge of planetary systems far, far away is increasing constantly, as new technologies continue to sharpen our gaze into space. To date, 3,700 planets have already been discovered outside our solar system. The planetary masses and radii of these exoplanets can be used to infer their mean density, but not their exact chemical composition and structure. The intriguing question about what these planets could look like is thus still open, according to Science Daily.

"Theoretically, we can assume various compositions, such as a world of pure water, a world of pure rock, and planets that have hydrogen-helium atmospheres and explore what radii are expected" explains Michael Lozovsky, a doctoral candidate in the group of Prof. Ravit Helled at the Institute for Computational Science at the University of Zurich.

 A new study suggests that plate tectonics -- a scientific theory that divides Earth into large chunks of crust that move slowly over hot viscous mantle rock -- could have been active from the planet's very beginning. The new findings defy previous beliefs that tectonic plates were developed over the course of billions of years, according to Science Daily.

The paper has important implications in the fields of geochemistry and geophysics. For example, a better understanding of plate tectonics could help predict whether planets beyond our solar system could be hospitable to life.

A novel tiny, soft robot with caterpillar-like legs capable of carrying heavy loads and adaptable to adverse environment was developed from a research led by City University of Hong Kong (CityU). This mini delivery-robot could pave way for medical technology advancement such as drugs delivery in human body.

Around the world, there has been research about developing soft milli-robots. But the CityU's new design with multi-legs helps reduce friction significantly, so that the robot can move efficiently inside surfaces within the body lined with, or entirely immersed in, body fluids such as blood or mucus, according to Science Daily.

Two of the closest galaxies to the Milky Way -- the Large and Small Magellanic Clouds -- may have had a third companion, astronomers believe.

Research published today describes how another "luminous" galaxy was likely engulfed by the Large Magellanic Cloud some three to five billion years ago, according to Science Daily.

ICRAR Masters student Benjamin Armstrong, the lead author on the study, said most stars in the Large Magellanic Cloud rotate clockwise around the centre of the galaxy.

A nearby exoplanet orbiting within the habitable zone of a star just 4.2 light-years from Earth may be home to a vast ocean, boosting its chances of supporting life.

Since its discovery, questions about the conditions at the surface of Proxima b have been swirling; the planet’s mass is just about 1.3 times that of Earth’s, and the red dwarf star it circles is similar in age to our sun, according to Daily Mail.

Studies over the last few years, however, have both bolstered hopes of its habitability and shot them down.