One of the biggest mysteries in science – dark energy – doesn't actually exist, according to researchers looking to solve the riddle of how the Universe is expanding. For the past 100 years, physicists have generally assumed that the cosmos is growing equally in all directions. They employed the concept of dark energy as a placeholder to explain unknown physics they couldn't understand, but the contentious theory has always had its problems. Now a team of physicists and astronomers at the University of Canterbury in Christchurch, New Zealand are challenging the status quo, using improved analysis of supernovae light curves to show that the Universe is expanding in a more varied, "lumpier" way.

The missing ingredient for cooking up stars in the same way you might steam your Christmas pudding has been spotted for the first time by astronomers. Much like a pressure cooker has a weight on top of its lid to keep the pressure in and get your festive dessert dense, moist and ready to eat, merging galaxies may need magnetic fields to create the ideal conditions for star formation. Until now, however, the existence of such a force had only been theorised rather than observed. An international team of researchers led by Imperial College astrophysicist Dr David Clements found evidence of magnetic fields associated with a disc of gas and dust a few hundred light-years across deep inside a system of two merging galaxies known as Arp220.

A groundbreaking achievement by scientists at the University of Houston is changing our understanding of climate and weather on Mars and providing critical insights into Earth’s atmospheric processes as well.

Unprecedented extreme heat represents a critical climate challenge, resulting in approximately 490,000 heat-related deaths globally each year, with 45% of these fatalities occurring in Asia.A study by The Hong Kong Polytechnic University (PolyU) has revealed that some existing heatwave indices are unable to accurately capture heatwave severity in diverse geographical regions and climate conditions. It is suggested to include humidity and indoor environmental conditions in identifying a dangerous heatwave. The development of a global heat risk framework and early warning systems are also recommended to alleviate the impact of heatwaves on human health. The research findings have been published in the international journal Nexus.

New studies led by researchers at the University of Central Florida offer for the first time a clearer picture of how the outer solar system formed and evolved based on analyses of trans-Neptunian objects (TNOs) and centaurs.

The findings, published in Nature Astronomy, reveal the distribution of ices in the early solar system and how TNOs evolve when they travel inward into the region of the giant planets between Jupiter and Saturn, becoming centaurs.

TNOs are small bodies, or ‘planetesimals,’ orbiting the sun beyond Pluto. They never accreted into planets, and serve as pristine time capsules, preserving crucial evidence of the molecular processes and planetary migrations that shaped the solar system billions of years ago. These solar system objects are like icy asteroids and have orbits comparable to or larger than Neptune’s orbit.

Prior to the new UCF-led study, TNOs were known to be a diverse population based on their orbital properties and surface colors, but the molecular composition of these objects remained poorly understood. For decades, this lack of detailed knowledge hindered interpretation of their color and dynamical diversity. Now, the new results unlock the long-standing question of the interpretation of color diversity by providing compositional information.