How do astronomers measure stars in a three-dimensional sky?

Anyone interested in astronomy realizes that the stars are scattered through three-dimensional space and not, as the ancients thought, points of light affixed to a celestial sphere. The night sky has often appeared to many as a kind of ceiling or vault. Stars in general are distributed randomly in space. Their various patterns and configurations … Read more

Ocean scientists measure sediment plume stirred up by deep-sea-mining vehicle

Credit: Unsplash/CC0 Public Domain What will be the impact to the ocean if humans are to mine the deep sea? It’s a question that’s gaining urgency as interest in marine minerals has grown. The ocean’s deep-sea bed is scattered with ancient, potato-sized rocks “polymetallic nodules” that contain nickel and cobalt—minerals that are in high demand … Read more

New technique to measure temperatures in combustion flames could lead to cleaner biofuels

Science Advances (2022). DOI: 10.1126/sciadv.abm7947″ width=”800″ height=”530″/> Measured and simulated krypton number densities in a sooting methane/air flame. (A) A photograph of the flame sized to the same spatial scale as (B). (B) Image plots of experimental (left) and simulated (right) krypton number densities throughout the flame. (C) Radial profiles of krypton number density at … Read more

Plants can measure the intensity of salt stress

yellow > green > blue. Credit: AG Kudla” width=”800″ height=”315″/> As an immediate reaction to elevated concentrations of salt (NaCl), the concentration of calcium in the cytosol of a specific group of cells increases within one minute. Shown in false colours: red (highest concentration) > yellow > green > blue. Credit: AG Kudla Unfavorable environmental … Read more

Merging Supermassive Black Holes Gives us a New Way to Measure the Universe

The study of black holes has advanced immensely in the past few years. In 2015, the first gravitational waves were observed by scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO). This finding confirmed what Einstein predicted a century before with General Relativity and offered new insight into black hole mergers. In 2019, scientists with the … Read more

How to Observe and Measure Naked-eye Sunspots – Sky & Telescope

Sunspot groups freckle the Sun in this photo taken with a 94-mm refracting telescope on April 21, 2022. Both lead spots in Active Regions 2993 and 2994 were visible without optical aid through a #14 welding glass. North is up.Bob King I’m a passionate naked-eye sunspot observer. No telescope or binoculars needed. I use eclipse … Read more