Orbiting about 360 miles (550 kilometers) above Earth, the Hubble Space Telescope captured this image of a spiral galaxy, called ESO 498-G5, with a fascinating spiral structure at its heart.
ESO 498-G5 is located 100 million light years away in the direction of a small, inconspicuous constellation in the southern hemisphere, Pyxis. Look closely at the center of the galaxy. See the spiral? What’s happening here is that ESO 498-G5’s spiral arms wind all the way into the galaxy’s center. That fact makes ESO 498-G5’s core look like a miniature spiral galaxy at the heart of the larger spiral.
Astronomers refer to the distinctive spiral-like bulge of galaxies such as ESO 498-G5 as disc-type bulges, or pseudobulges. Meanwhile, bright elliptical centers of spiral galaxies are called classical bulges.
Bottom line: The spiral galaxy ESO 498-G5 has a smaller spiral structure at its heart. This type of structure in a spiral galaxy is called a pseudobulge. Bright elliptical centers of spiral galaxies are called classical bulges. The Hubble Space Telescope took this photo.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.