Recently, the National Aeronautics and Space Administration (NASA) shared an image of a rotating spiral galaxy. This galaxy is hidden within the largest constellation in the sky, Hydra, and it also contains a type Ia supernova, which has caught the attention of astronomers.
According to NASA, the Hubble Space Telescope captured the image of this spiral galaxy named NGC 3285B. It is located within the Hydra constellation, approximately 137 million light-years away from Earth.
Hydra is the largest constellation in terms of area among the 88 constellations, resembling patches covering the entire sky. It is also the longest constellation, spanning 100 degrees across the sky. From one side of Hydra to the other is equivalent to about 200 full moons lined up next to each other (note: the apparent size of a full moon from Earth is approximately 0.5 degrees).
NGC 3285B is a member of the Hydra Galaxy Cluster, which is one of the largest galaxy clusters in the nearby universe. Galaxy clusters are composed of hundreds to thousands of galaxies bound together by gravity. At the center of the Hydra Galaxy Cluster are two massive elliptical galaxies, each with a diameter of approximately 150,000 light-years, about 50% larger than the Milky Way galaxy.
NGC 3285B is located on the outskirts of the Hydra Galaxy Cluster, far from the central massive galaxies. This galaxy attracted the attention of the Hubble Space Telescope because it gave birth to a type Ia supernova named SN 2023xqm in 2023. The supernova can be seen in the image, appearing as a blue dot on the left edge of the galaxy’s disk.
Type Ia supernovae are caused by the explosion of a dense stellar core known as a white dwarf through nuclear fusion, reaching a brightness 5 billion times that of the Sun in a very short period of time.
In a previous report, Type Ia supernovae exhibit consistent peak brightness. This characteristic allows astronomers to indirectly measure distances of celestial objects using Type Ia supernovae – we know how bright Type Ia supernovae should be, so we can determine how distant they are based on how dim they appear.
Astronomers have various methods to measure distances of celestial objects, but Type Ia supernovae are one of the most useful and accurate tools because of their brightness.
NASA mentioned that astronomers observed NGC 3285B using the Hubble Space Telescope based on an observation program targeting 100 Type Ia supernovae.
By observing each supernova in ultraviolet, visible, and near-infrared light, astronomers are trying to unravel the effects of distance and dust, both of which can make supernovae appear redder than they actually are.