Today's ESA/Hubble Picture of the Week features a galaxy that Hubble has captured multiple times over more than 20 years. The ...

An image of the Cepheid variable star RS Puppis. The most accurate observation to date of distant stars that periodically change in brightness may spark a rethink of the rate at which the universe ...

On the night of Oct. 5, 1923, Edwin Hubble observed a strange star that flickered in intensity at regular intervals. The star ...

Astronomers from the University of Warsaw, Poland and elsewhere have detected a new classical Cepheid variable star. The newfound star, which received designation OGLE-GD-CEP-1884, has the longest ...

In 1925, Edwin Hubble's observation of Cepheid variables in the Andromeda galaxy revolutionized astronomy, proving the existence of galaxies beyond the Milky Way. This discovery, aided by telescopes ...

A hundred years ago, astronomer Edwin Hubble dramatically expanded the size of the known universe. At a meeting of the American Astronomical Society in January 1925, a paper read by one of his ...

An artist's illustration of the Big Bang. The universe is expanding. But depending on where we look, it's doing so at bafflingly different speeds. The problem is known as the Hubble tension, and it ...

Yardsticks are very useful around the house when you need a measurement. (I have also used them to fish out toys the cat knocked under a low piece of furniture.) They are standards by which we can ...

Henrietta Leavitt joined the Harvard College Observatory as a volunteer in 1895. She was appointed to the permanent staff in 1902, and eventually became chief of the photometry department. She worked ...

This week on Looking Up guest host Caitlyn Voige illuminates a luminary by the name of Henrietta Swan Leavitt. When we look up into the night sky, stars look immeasurably small and distant, unchanging ...

A new survey of the stars in our galaxy reveals something unexpected: The Milky Way isn’t flat. Our galaxy is usually depicted as a flat disc of stars, but according to new research from the Chinese ...