Hubble's colorful snapshots show that the universe always looks festive. Dwarf irregular galaxy UGC 8091 is a gorgeous example. The dizzying interaction of matter and energy creates dazzling blue newborn stars that look like a string of holiday lights. They are encased in a cocoon of hot pink hydrogen gas. This dwarf galaxy consists of approximately 1 billion stars. That sounds like a lot, but it's only 1/100th the number of stars in our galaxy.

In this holiday image from NASA and the European Space Agency's (ESA) Hubble Space Telescope, one billion stars in the UGC 8091 galaxy resemble a glowing ball. Image source: ESA/Hubble, NASA, ESA, Yumi Choi (NSFNOIRLab), Karoline Gilbert (STScI), Julianne Dalcanton (University of Washington Center for Computational Astrophysics/Flatiron Institute)

The early universe was filled with dwarf galaxies, which eventually merged into the majestic spiral galaxies that surround us today. This little galaxy, UGC 8091, is belatedly located 7 million light-years away and has only recently begun to display its shimmering tapestry.

The Hubble Space Telescope is an iconic facility for space exploration, launched into orbit in 1990. Hubble revolutionized astronomy by providing an unprecedentedly clear and deep view of the universe, far beyond the distortions of Earth's atmosphere. Source: NASA

This dwarf galaxy is about 7 million light-years away from Earth in the constellation Virgo. It is considered an "irregular galaxy" because it does not have an ordered spiral or elliptical appearance. Instead, the stars that make up this celestial conglomeration look more like a string of shining lights than a galaxy. Some irregular galaxies may have become tangled together due to intense internal activity, while others formed due to interactions with neighboring galaxies. This creates a class of galaxies of varying sizes and shapes, including this diffuse galaxy of stars.

The image was created from a combination of 12 camera filters, with light stretching from the mid-ultraviolet to the red end of the visible spectrum. The red patches are likely interstellar hydrogen molecules that glow when excited by light from hot, energetic stars. The other sparks shown in this photo are composed of older stars. A distant and diverse array of galaxies appears in the background, captured by Hubble's sharp perspective.

The data used in this image were taken by Hubble's Wide Field Camera 3 and Advanced Camera for Surveys between 2006 and 2021. Among other things, the observational program involved in this image aimed to study the role that dwarf galaxies played billions of years ago in reheating hydrogen gas that cooled as the universe expanded after the Big Bang. Astronomers are also studying the composition of dwarf galaxies and their stars to reveal the evolutionary connections between these ancient galaxies and modern galaxies like ours.

The Hubble Space Telescope is an international collaboration between NASA and ESA. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, is responsible for the science operations of the Hubble and Webb telescopes. The Space Telescope Science Institute is operated for NASA by the Association of Universities for Research in Astronomy in Washington, DC.