Hubble Star Cluster
Messier 92 is a globular cluster -- a collection of stars that orbit a galactic core -- located in the constellation of Hercules. Messier 92 contains around 330,000 stars. ESA/Hubble & NASA Acknowledgment: Gilles Chapdelaine

The Hubble Space Telescope, which was launched into orbit on April 24, 1990, has spent 25 years exploring the universe and it continues to impress. Hubble's photos have been used to better understand what's going on in our galaxy and in the early universe. From planets to nebulae, Hubble has taken so many incredible photos. Here's just a small sample of what Hubble has been up to for over two decades.


Hubble Jupiter
The Hubble Space Telescope has spent decades observing the planets in our solar system. Hubble's images of Jupiter show how its Great Red Spot has shrunk over the years. NASA, ESA, and A. Simon (Goddard Space Flight Center)

Hubble may be known for its flashy photos of star clusters and detailed glimpses into galaxies, but the space telescope also is really good at taking photos of planets. Hubble's photos of Jupiter have been used to track the growth of the planet's Great Red Spot over 10 years and the dancing auroras seen at the gas giant's poles.

Hubble also has snapped portraits of Venus, Uranus, Neptune, Mars and Saturn. The space telescope also has produced images of Pluto -- which got demoted to dwarf planet after Hubble was launched -- and one of the photos led to the discovery of a fifth moon orbiting it.

Hubble Saturn
Hubble captured this quadruple transit across Saturn in 2009. Titan is in the upper right while Enceladus, Dione and Mimas are seen to the left above the planet's ring system. NASA, ESA and the Hubble Heritage Team (STScI/AURA). Acknowledgment: M. Wong (STScI/UC Berkeley) and C. Go (Philippines)

Black Holes, Supernovas And More

Hubble Black Hole Signature
Hubble's Space Telescope Imaging Spectrograph was used by astronomers to calculate the supermassive black hole at the center of the galaxy M84. Gary Bower, Richard Green (NOAO), the STIS Instrument Definition Team, and NASA

Hubble also helps solve cosmic mysteries. Astronomers used a photo of the galaxy M84 to trace the motions of gas being pulled by the supermassive black hole at the center of the galaxy. Data from Hubble's Space Telescope Imaging Spectrograph (STIS) was used to measure the speed of the gas moving around near the black hole. Astronomers then used the speed of the gas -- around 880,000 miles per hour -- to calculate the mass of the black hole, around 300 million solar masses. The supermassive black hole at the center of the Milky Way -- Sagittarius A* (Sgr A*) -- weighs in at 3 million solar masses. Hubble also has captured photos of quasars -- "intensely powerful centers of distant, active galaxies, powered by a huge disc of particles surrounding a supermassive black hole" -- supernovas and the remnant structure left behind the death of a star.

Supernova Remnant
The remnant of a supernova named Cassiopeia A. NASA, ESA, and the Hubble Heritage STScI/AURA)-ESA/Hubble Collaboration

So Many Stars And Galaxies

Pillars of Creation
Hubble's famed image of the Eagle Nebula's Pillars of Creation. The dust and gas are being torn apart by young stars. NASA, ESA/Hubbleand the Hubble Heritage Team

Hubble has changed how we view the universe, but it's easy to forget that when you're busy staring at the incredible images of stellar nurseries and galaxies. The official Hubble 25th anniversary image of Westerlund 2 is teeming with stars.

Sombrero Galaxy
Messier 104, beeter known as the Sombrero galaxy, is located 28 million light-years from Earth. NASA/ESA and The Hubble Heritage Team STScI/AURA)

Galaxies are another popular subject for Hubble. The space telescope has captured ancient galaxies, used galaxies as a magnifying lens to peer deep into the early universe, and snapped photos of interacting galaxies.

Cosmic Rose
The interacting galaxies known as Arp 273 combine to form a cosmic rose. NASA, ESA and the Hubble Heritage Team (STScI/AURA)
Horsehead Nebula
The Horsehead Nebula is located 1,300 light-years away. NASA, ESA, and the Hubble Heritage Team (AURA/STScI)
Hubble Galaxies
Hubble is now capable of taking images like the one seen here. Taken by the Advanced Camera for Surveys, the Hubble Ultra Deep Field image features around 10,000 galaxies. NASA, ESA, and S. Beckwith (STScI) and the HUDF Team

Perhaps the coolest thing of late has been the fly-throughs into Hubble's images. Flying through Westerlund 2, the Antennae Galaxies or a 3D fly-through of the Orion Nebula gives you a better understanding of the detail captured by Hubble.

While Hubble will be remembered for its vast contributions to astronomy, the space telescope soon will make way for the James Webb Space Telescope. NASA will launch the new instrument in 2018. The JWST will have a primary mirror with a diameter of 6.5 meters -- Hubble's primary mirror has a diameter of 2.4 meters -- and will explore the very early universe.