Posts by 

Theresa Wiegert

Milky Way center: Threads of hot gas and magnetic fields

An astronomer combined 2 decades worth of X-ray data with radio observations, creating an extraordinary image of the Milky Way center.

The most ancient spiral galaxy yet

Astronomers have discovered a spiral galaxy surprisingly near the beginning of the universe, making it the most ancient spiral galaxy found so far.

Alien stars found in our Milky Way

Astronomers precisely measured the ages of 100 red giant stars. Many are alien stars from another galaxy, which merged with ours 10 billion years ago.

Sharks navigate using Earth’s magnetic field

Longstanding mystery solved! New research shows that - just as lobsters, turtles and some birds do - sharks navigate using Earth's magnetic field,

Cool sun image

EarthSky readers submit wonderful photos to us every day. This week we received this interesting composite image of the sun, our nearest star.

How do you measure the mass of a star?

Binary stars - a star system consisting of two stars - are extremely useful. They give all the information needed to measure the stars masses'. Here is how.

Map of Milky Way halo reveals dark matter ocean

The gravity of the Large Magellanic Cloud - one of the Milky Way's satellite dwarf galaxies - is collecting stars behind it in a trail, like the wake from a boat, as it travels through our galaxy's halo.

Going up and coming down this week

Within hours of each other, one rocket left the Earth on April 28, 2021, and one cargo space ship returned on April 29 - via a planned destruction during re-entry - after having been attached to the International Space Station for a year.

Radio waves from famous FRB surprisingly long and late

Astronomers have managed to detect very long wavelength radio emission from a well-studied, repeating fast radio burst, called FRB 20180916B. What's more, the longer wavelengths arrive 3 days after the shorter wavelength counterpart of the signal! Why?

Chemical fingerprint reveals a migrating exoplanet

The chemical fingerprint of exoplanet HD 209458b's atmosphere reveals as many as 6 molecules and that it has migrated inwards from its birthplace much farther out in its star system.