Showing 20 articles starting at article 261

< Previous 20 articles        Next 20 articles >

Categories: Offbeat: Space, Paleontology: Climate

Return to the site home page

     (via sciencedaily.com)     Original source 

The earliest galaxies are thought to have formed as the gravitational pull of dark matter, which has been impossible to study directly, slowly drew in enough hydrogen and helium to ignite stars. But astrophysicists now show that after the Big Bang, hydrogen and helium gas bounced at supersonic speeds off dense, slowly moving clumps of cold dark matter. When the gas fell back in millennia later, stars formed all at once, creating small, exceptionally bright galaxies. If models of cold dark matter are correct, the James Webb Space Telescope should be able to find patches of bright galaxies in the early universe, potentially offering the first effective test for theories about dark matter. If it doesn't, scientists have to go back to the drawing board with dark matter.

     (via sciencedaily.com)     Original source 

The James Webb Space Telescope observed 19 nearby face-on spiral galaxies in near- and mid-infrared light as part of its contributions to the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program.

     (via sciencedaily.com)     Original source 

The next generation of advanced telescopes could sharpen the hunt for potential extraterrestrial life by closely scrutinizing the atmospheres of nearby exoplanets, new research suggests.

     (via sciencedaily.com)     Original source 

Scientists have identified 18 new tidal disruption events (TDEs) -- extreme instances when a nearby star is tidally drawn into a black hole and ripped to shreds. The detections more than double the number of known TDEs in the nearby universe.

     (via sciencedaily.com)     Original source 

Ground-penetrating radar on board NASA's Mars Perseverance rover has confirmed that the Jezero Crater, formed by an ancient meteor impact just north of the Martian equator, once harbored a vast lake and river delta. Over eons, sediment deposition and erosion within the crater shaped the geologic formations visible on the surface today. The discovery of lake sediments reinforces the hope that traces of life might be found in soil and rock samples collected by Perseverance.

     (via sciencedaily.com)     Original source 

Physicists discovered stars near the edge of the Milky Way travel more slowly than those closer to its center -- a surprise suggesting our galaxy's gravitational core may have less dark matter than previously thought.

     (via sciencedaily.com)     Original source 

'Hidden' stars including a new type of elderly giant nicknamed an 'old smoker' have been spotted for the first time by astronomers. The mystery objects exist at the heart of our Milky Way galaxy and can sit quietly for decades -- fading almost to invisibility -- before suddenly puffing out clouds of smoke, according to a new study.

     (via sciencedaily.com)     Original source 

The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?

     (via sciencedaily.com)     Original source 

A new method predicts how much flooding a coastal community is likely to experience as hurricanes evolve due to climate change. Using New York as a test case, the model predicts Hurricane Sandy-level flooding will occur roughly every 30 years by 2099.

     (via sciencedaily.com)     Original source 

New research shows that atmospheric pressure fluctuations that pull gases up from underground could be responsible for releasing subsurface methane into Mars' atmosphere; knowing when and where to look for methane can help the Curiosity rover search for signs of life.

     (via sciencedaily.com)     Original source 

A new way to measure the ocean oxygen level and its connections with carbon dioxide in the Earth's atmosphere during the last ice age could help explain the role oceans played in past glacial melting cycles and improve predictions of how ocean carbon cycles will respond to global warming.

     (via sciencedaily.com)     Original source 

An international team of astronomers have found a new and unknown object in the Milky Way that is heavier than the heaviest neutron stars known and yet simultaneously lighter than the lightest black holes known.

     (via sciencedaily.com)     Original source 

A research team has for the first time discovered anomalous meter-sized rocks on the lunar surface that are covered in dust and presumably exhibit unique properties -- such as magnetic anomalies. These findings help to understand the processes that form and change the lunar crust.

     (via sciencedaily.com)     Original source 

The new theoretical research proposes that animal size over time depends on two key ecological factors.

     (via sciencedaily.com)     Original source 

Southern Africa contains the vast majority of the world's remaining populations of both black and white rhinoceroses (80% and 92%, respectively). The region's climate is changing rapidly as a result global warming. Traditional conservation efforts aimed at protecting rhinos have focused on poaching, but until now, there has been no analysis of the impact that climate change may have on the animals. A research team has recently reported that, though the area will be affected by both higher temperatures and changing precipitation, the rhinos are more sensitive to rising temperatures, which will quickly increase above the animals' acceptable maximum threshold.

     (via sciencedaily.com)     Original source 

Researchers have discovered the oldest black hole ever observed, dating from the dawn of the universe, and found that it is 'eating' its host galaxy to death.

     (via sciencedaily.com)     Original source 

Researchers have developed a 10-centimeter-diameter glass metalens that can image the sun, the moon and distant nebulae with high resolution. It is the first all-glass, large-scale metalens in the visible wavelength that can be mass produced using conventional CMOS fabrication technology.

     (via sciencedaily.com)     Original source 

When combined with data from tree-ring records, stalagmites can open up a unique archive to study natural climate fluctuations, a research team has demonstrated. The researchers analyzed the isotopic composition of oxygen in a stalagmite formed from calcareous water in a cave in southern Germany. In conjunction with the data acquired from tree rings, they were able to reconstruct short-term climate fluctuations over centuries and correlate them with historically documented environmental events.

     (via sciencedaily.com)     Original source 

A 10-month mission demonstrated three elements of the plan to beam solar power from space to Earth.

     (via sciencedaily.com)     Original source 

New research shows the early lunar crust which makes up the surface of the Moon was considerably enriched in water more than 4 billion years ago, counter to previously held understanding.