Skip to main content

A small, fuzzy dwarf galaxy in our neighborhood captured by Hubble

This week’s image from the Hubble Space Telescope shows a galaxy in our backyard, cosmically speaking, taken as part of a project to image nearby galaxies. Galaxy UGCA 307 is located 26 million light-years away in the constellation of Corvus, or The Crow, a small constellation visible from the southern hemisphere which was documented as far back as 1,000 years BCE.

There is just a small cluster of stars within this galaxy, as it is a type called a dwarf galaxy. These are defined as galaxies with just a few billion stars, which sounds like a lot until you compare it to the hundreds of billions of stars that are found in our galaxy, the Milky Way.

Related Videos
UGCA 307 hangs against an irregular backdrop of distant galaxies in this image from the NASA/ESA Hubble Space Telescope. The small galaxy consists of a diffuse band of stars containing red bubbles of gas that mark regions of recent star formation, and lies roughly 26 million light-years from Earth in the constellation Corvus. Appearing as just a small patch of stars, UGCA 307 is a diminutive dwarf galaxy without a defined structure — resembling nothing more than a hazy patch of passing cloud.
UGCA 307 hangs against an irregular backdrop of distant galaxies in this image from the NASA/ESA Hubble Space Telescope. The small galaxy consists of a diffuse band of stars containing red bubbles of gas that mark regions of recent star formation, and lies roughly 26 million light-years from Earth in the constellation Corvus. ESA/Hubble & NASA, R. Tully

UGCA 307 doesn’t have a lot of structure, again unlike our Milky Way with its central bar and clearly defined spiral arms. Instead, this galaxy is wispy and hazy with a spattering of stars.

Still, there are features visible in this galaxy, like the regions of bright glowing red where new stars are forming. When stars are young they give off ultraviolet radiation, which illuminates nearby gas and causes it to glow brightly.

The image was taken using Hubble’s Advanced Camera for Surveys (ACS) instrument, which looks in the same part of the electromagnetic spectrum that the human eye can perceive, called the visible light or optical range. It doesn’t see the ultraviolet radiation from the new stars, but it does see the effect that radiation has on the clouds of dust around star-forming regions.

“This image is part of a Hubble project to explore every known nearby galaxy, giving astronomers insights into our galactic neighborhood,” Hubble scientists explain.

“Before this set of observations, almost three-quarters of nearby galaxies had been investigated by Hubble in enough detail to spot the brightest stars and build up an understanding of the stars populating each galaxy. This Hubble project set out to explore the remaining quarter of nearby galaxies by taking advantage of short gaps in Hubble’s observing schedule.”

Editors' Recommendations

Astronomers share early images from James Webb’s galaxy survey
Images of four example galaxies selected from the first epoch of COSMOS-Web NIRCam observations, highlighting the range of structures that can be seen. In the upper left is a barred spiral galaxy; in the upper right is an example of a gravitational lens, where the mass of the central galaxy is causing the light from a distant galaxy to be stretched into arcs; on the lower left is nearby galaxy displaying shells of material, suggesting it merged with another galaxy in its past; on the lower right is a barred spiral galaxy with several clumps of active star formation.

One of the major aims of the James Webb Space Telescope is to observe some of the earliest galaxies in the universe, and to do that it needs to be able to see extremely distant objects. But looking at a particular very old galaxy in detail is only half of the problem. To truly understand the earliest stages of the universe, astronomers also need to see how these very old galaxies are distributed so they can understand the large-scale structure of the universe.

That's the aim of the COSMOS-Web program, which is using James Webb to survey a wide area of the sky and look for these rare, ancient galaxies. It aims to study up to 1 million galaxies during over 255 hours of observing time, using both Webb's near-infrared camera (NIRCam) and its mid-infrared instrument (MIRI) camera. While there is still plenty of observing left to do, the researchers in the COSMOS-Web program recently shared some of their first results.

Read more
Water was present in our solar system before the sun formed
This artist’s impression shows the planet-forming disc around the star V883 Orionis. In the outermost part of the disc water is frozen out as ice and therefore can’t be easily detected. An outburst of energy from the star heats the inner disc to a temperature where water is gaseous, enabling astronomers to detect it. The inset image shows the two kinds of water molecules studied in this disc: normal water, with one oxygen atom and two hydrogen atoms, and a heavier version where one hydrogen atom is replaced with deuterium, a heavy isotope of hydrogen.

You might assume that there has always been water on Earth -- that water was there from the very beginning when our planet formed. But scientists increasingly think that water on Earth may have originated elsewhere, and been carried here by comets. However, the water in the comets had to come from somewhere, and astronomers recently made a discovery which could shed light on how that water was found in the solar system.

The researchers used the Atacama Large Millimeter/submillimeter Array (ALMA), a radio telescope array in Chile, to study a planet-forming disc around the star V883 Orionis, looking for water there to see how it would be transported as the disk evolves into planets.

Read more
Hubble captures a messy irregular galaxy which hosted a supernova
The irregular spiral galaxy NGC 5486 hangs against a background of dim, distant galaxies in this image from the NASA/ESA Hubble Space Telescope. The tenuous disk of the galaxy is threaded through with pink wisps of star formation, which stand out from the diffuse glow of the galaxy’s bright core.

This week's image from the Hubble Space Telescope shows a dramatic spiral galaxy called NGC 5486, which is shot through with wisps of pink showing regions where new stars are being born.

Located 110 million light-years away in the famous constellation of Ursa Major, this galaxy is a type called an irregular spiral galaxy because its arms are wandering and indistinct. If you compare the image of this galaxy to one of a quintessential spiral galaxy like NGC 2336, you'll see that a non-irregular spiral galaxy has clearly defined arms that reach out from its center and are symmetrical.

Read more