An image from the Hubble Space Telescope shared this week by NASA shows a nearby galaxy, ESO 300-16. Unlike our Milky Way, which is a type called a spiral galaxy with a clear central bulge and defined spiral arms reaching out from its center, this neighborhood galaxy is loose and diffuse, looking more like a spattering of stars than anything with a clear structure. Hubble scientists describe it as a “sparkling cloud.”
The galaxy is a type called an irregular galaxy, due to its lack of clear shape. Its stars clump together in a soft bubble form, and it is located nearly 29 million light-years away in the direction of the constellation Eridanus.
“This observation is one of a series which aims to get to know our galactic neighbors,” Hubble scientists explain in a statement. “Hubble has observed around three-quarters of known galaxies within about 10 megaparsecs of Earth in enough detail to resolve their brightest stars and establish distances to these galaxies. A team of astronomers proposed using small gaps in Hubble’s observing schedule to acquaint ourselves with the remaining quarter of these nearby galaxies.”
The project is called Every Known Nearby Galaxy and is designed to maximize Hubble’s observing time. Time on Hubble is in high demand, so astronomers have to submit proposals for how and why they want to use Hubble for their observations far in advance. This is a competitive process, with experts deciding what the best of use Hubble’s limited time would be and filling out the schedule as much as they can. However, there are some small gaps between observations, such as when the telescope has to move to point to different parts of the sky for different observations.
Researchers make use of this 2-3% of time on Hubble which isn’t going toward primary observations to make other smaller observations like the Every Known Nearby Galaxy project. This has resulted in a series of images of our galactic neighbors, including ghostly galaxy NGC 6684, fuzzy galaxy LEDA 48062, and dwarf galaxy UGCA 307.
