Monday, October 2

Astronomy

Astronomy

‘Supercontinent’ could make Earth uninhabitable in 250m years, study predicts | Geology

The formation of a supercontinent on Earth could wipe out humans and any other mammals that are still around in 250m years, according to a study.The mass extinction would be caused primarily by heat stress as a result of greater volcanic activity that would put twice as much carbon dioxide into the atmosphere as current levels, an older sun that would emit more radiation and the extent of inland deserts in the tropics.The supercontinent Pangea Ultima is expected to take shape when all the current continents merge together in the distant future. The paper, which was published on Monday in Nature Geoscience, is the first attempt to model how extreme the climate might become from that geological rearrangement.Using a UK Met Office climate model and the University of Bristol supercomputer, the...
New findings suggest Moon may have less water than previously thought
Astronomy

New findings suggest Moon may have less water than previously thought

A team including Southwest Research Institute's Dr. Raluca Rufu recently calculated that most of the Moon's permanently shadowed regions (PSRs) are at most around 3.4 billion years old and can contain relatively young deposits of water ice. Water resources are considered key for sustainable exploration of the Moon and beyond, but these findings suggest that current estimates for cold-trapped ices are too high. The current tilt of the Moon's spin axis combined with its orbital inclination -- the angle to Earth's orbital plane -- and the Sun's low angle creates permanent shadows at its poles. PSRs are some of the coldest spots in the solar system, allowing them to trap volatile chemicals, including water ice, that would immediately transform directly from a solid to a gas in the harsh, airle...
Hurricane Lee Traverses the Warm Atlantic
Astronomy

Hurricane Lee Traverses the Warm Atlantic

Satellite image of Hurricane Lee captured on September 12, 2023, by Geostationary Operational Environmental Satellite 16.The major storm fluctuated in intensity as it approached the U.S. East Coast.On September 12, 2023, Hurricane Lee continued its slow west-northwest trajectory across the Atlantic Ocean. The Geostationary Operational Environmental Satellite 16 (GOES-16) acquired this image of the major storm at approximately 1 p.m. Eastern Time (17:00 UTC) as it advanced toward the southeastern United States. The satellite is operated by the National Oceanic and Atmospheric Administration (NOAA); NASA helps develop and launch the GOES series of satellites.Around this time, the center of the hurricane was located about 500 miles (800 kilometers) south of Bermuda and moving at 6 miles (9 ki...
DART had a surprising impact on its target, according to recent observations
Astronomy

DART had a surprising impact on its target, according to recent observations

This Hubble image shows debris from Didymos about one day after NASA's DART spacecraft slammed into it. Credit: NASA, ESA, STScI, J. Li (PSI) After NASA's DART mission slammed into asteroid Dimorphous in September 2022, scientists determined the impact caused tons of rock to be ejected from the small asteroid's surface. But more importantly, DART's impact altered Dimorphos' orbital period, decreasing it by about 33 minutes. However, a group of researchers measured the orbital period about a month later and discovered that it had increased to 34 minutes—1 minute longer than the first measurements. Ev...
A Bizarre Pulsar Switches Between Two Brightness Modes. Astronomers Finally Figured Out Why.
Astronomy

A Bizarre Pulsar Switches Between Two Brightness Modes. Astronomers Finally Figured Out Why.

Pulsars are the lighthouses of the universe. These rotating dead stars shoot twin jets of radiation from their poles, usually with a predictable rhythm. But sometimes pulsars behave strangely, and one pulsar in particular has had astronomers scratching their heads for years. It’s called PSR J1023+0038, and a decade ago, it shut off its jets and began oscillating between two brightness levels in an unpredictable pattern. Now, scientists think they understand why: it is busy eating a neighboring star. When a supergiant star approaches the end of its lifespan, it will explode and collapse into a back hole if it has enough mass, or into a neutron star if it does not. Neutron stars are the remaining, ultra-dense cores of the old star. They are often very fast-spinning, and a subset of them be...