bow shock tagged posts

Zeta Ophiuchi has had an interesting life. It began as a typical large star about twenty times more massive than the sun. It spent its days happily orbiting a large companion star until its companion exploded as a supernova about a million years ago. The explosion ejected Zeta Ophiuchi, so now it is speeding away through interstellar space. Of course, the supernova also expelled the outer layers of the companion star, so rather than empty space, our plucky star is speeding through the remnant gas as well. As they say on Facebook, it’s complicated. And that’s great news for astronomers, as a recent study shows.

Zeta Ophiuchi is most famous for be...

The record-breaking beam is powered by a pulsar, a rapidly rotating collapsed star with a strong magnetic field.

With its tremendous scale, this beam may help explain the surprisingly large numbers of positrons, the antimatter counterparts to electrons, throughout the Milky Way galaxy.

Astronomers first discovered the beam, or filament, in 2020, but they did not know its full length because it extended beyond the edge of the Chandra detector. New Chandra observations by the same pair of researchers taken in February and November 2021 show the filament is about three times as long as originally seen. The filament spans about half the diameter of the full Moon on the sky, making it the longest one from a pulsar as seen from Earth.

“It’s amazing that a pulsar that’s only 10 mile...

This image represents one of the traditional proposed mechanisms for accelerating particles across a shock, called a shock drift acceleration. The electrons (yellow) and protons (blue) can be seen moving in the collision area where two hot plasma bubbles collide (red vertical line). The cyan arrows represent the magnetic field and the light green arrows, the electric field. Credits: NASA Goddard’s Scientific Visualization Studio/Tom Bridgman, data visualizer

High above the surface, Earth’s magnetic field constantly deflects incoming supersonic particles from the sun. These particles are disturbed in regions just outside of Earth’s magnetic field – and some are reflected into a turbulent region...

This NASA/ESA Hubble Space Telescope image features the star cluster Trumpler 14. One of the largest gatherings of hot, massive and bright stars in the Milky Way, this cluster houses some of the most luminous stars in our entire galaxy. Credit: NASA & ESA, Jesús Maíz Apellániz (Instituto de Astrofisica de Andalucia)

When single stars join forces, they create truly breathtaking scenes to rival even the most glowing of nebulae or swirling of galaxies. A new image features the star cluster Trumpler 14. One of the largest gatherings of hot, massive and bright stars in the Milky Way, this cluster houses some of the most luminous stars in our entire galaxy.

Around 1100 open clusters have so far been discovered within the Milky Way, although many more are thought to exist...