For over two decades astronomers have been patiently monitoring the fading glow of a supernova in a nearby galaxy. They've been looking for a suspected companion star that pulled off almost all of the hydrogen from the doomed star that exploded. At last Hubble's ultraviolet-light sensitivity pulled out the blue glow of the star from the cluttered starlight in the disk of the galaxy. This observation confirms the theory that the supernova originated in a double-star system where one star fueled the mass-loss from the aging primary star. The surviving star's brightness and estimated mass provide... Read more

The birth of massive galaxies, according to galaxy formation theories, begins with the buildup of a dense, compact core that is ablaze with the glow of millions of newly formed stars. Evidence of this early construction phase, however, has eluded astronomers until now. Astronomers identified a dense galactic core, dubbed "Sparky," using a combination of data from Hubble and Spitzer, other space telescopes, and the W.M. Keck Observatory in Hawaii. Hubble photographed the emerging galaxy as it looked 11 billion years ago, just 3 billion years after the birth of our universe in the big bang.

This... Read more

Supernovae are the most powerful stellar explosions in the universe. Some of them are produced by the detonation of a white dwarf, the stripped-down core of an ordinary star at the end of its life. But 12 years ago, astronomers began noticing weak stellar blasts, a kind of mini-supernova. When one such explosion occurred in the galaxy NGC 1309, astronomers looking through Hubble archival images found for the first time the star system that produced the supernova blast of a white dwarf.

The inset panel from 2013 shows the supernova; archival Hubble data from 2005 and 2006 show the progenitor system... Read more

Astronomers using NASA's Hubble Space Telescope have unexpectedly discovered the most distant cosmic magnifying glass yet, produced by a monster elliptical galaxy. The galaxy, seen here as it looked 9.6 billion years ago, is so massive that its gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing. In the Hubble image, the galaxy is the red object in the enlarged view at left.

The object behind the cosmic lens is a tiny spiral galaxy undergoing a rapid burst of star formation. Its light has taken 10.7 billion years to arrive here. In the... Read more

It seems like our compulsive universe can be downright capricious when it comes to making oddball-looking things in the cosmos. The latest surprise to Hubble astronomers is a 100,000-light-year-long structure that looks like a string of pearls twisted into a corkscrew shape. This Slinky-like structure forms a bridge between two giant elliptical galaxies that are colliding. The "pearls" on the Slinky are superclusters of blazing, blue-white, newly born stars. The whole assembly, which looks like a tug-of-war, must result from the gravitational tidal forces present in the collision.

If that's not... Read more

Jupiter's monster storm, the Great Red Spot, was once so large that three Earths would fit inside it. But new measurements by NASA's Hubble Space Telescope reveal that the largest storm in our solar system has downsized significantly. The red spot, which has been raging for at least a hundred years, is only the width of one Earth. What is happening? One possibility is that some unknown activity in the planet's atmosphere may be draining energy and weakening the storm, causing it to shrink. The Hubble images were taken in 1995, 2009, and 2014.

Join Hubble astronomers for further discussion about... Read more

If you need to check whether the prescription for your eye glasses or contact lenses is still accurate, you visit an ophthalmologist for an eye exam. The doctor will ask you to read an eye chart, which tests your visual acuity. Your score helps the doctor determine whether to change your prescription.

Astronomers don't have a giant eye chart to check the prescription for natural cosmic lenses, created by galaxy clusters. The gravity of these cosmic lenses warps space around them, magnifying and brightening the light from distant objects behind them. Without these lenses, background objects would be... Read more

Nearly 2,000 planets have been confirmed to be orbiting other stars in our galaxy. But the details of planet birth and formation are sparse. The conventional wisdom, dating back to a hypothesis by philosopher Immanuel Kant in the late 1700s, considered the orbit of the planets in our solar system to be the skeleton of disks of dust and gas that swirled around the newborn sun. The dust particles clumped together to build planets from the ground up.

More than 200 years later the Hubble Space Telescope's exquisite resolution and sensitivity have allowed astronomers to discover dusty disks around... Read more

Comet Siding Spring is plunging toward the Sun along a roughly 1-million-year orbit. The comet, discovered in 2013, was within the radius of Jupiter's orbit when the Hubble Space Telescope photographed it on March 11, 2014. Hubble resolves two jets of dust coming from the solid icy nucleus. These persistent jets were first seen in Hubble pictures taken on Oct. 29, 2013. The feature should allow astronomers to measure the direction of the nucleus's pole, and hence, rotation axis. The comet will make its closest approach to our Sun on Oct. 25, 2014, at a distance of 130 million miles, well outside... Read more

This colorful Hubble Space Telescope mosaic of a small portion of the Monkey Head Nebula unveils a collection of carved knots of gas and dust silhouetted against glowing gas. The cloud is sculpted by ultraviolet light eating into the cool hydrogen gas. As the interstellar dust particles are warmed from the radiation from the stars in the center of the nebula, they heat up and begin to glow at infrared wavelengths, as captured by Hubble. The space photo superficially resembles the "The Great Wave" print by 19th century Japanese artist Katsushika Hokusai.