New low-mass galaxy discovered

Astronomers report the discovery of a new galaxy in the constellation Corvus. The newly discovered galaxy, named Corvus A, is relatively low-mass, gas-rich and isolated. The discovery was presented in a research paper published on July 3 on the preprint server arXiv.

One project that has detected many nearby low-mass galaxy candidates is the SEMi-Automated Machine LLearning Search for Semi-resolved galaxies (SEAMLESS). The project relies on masking the high surface brightness emission from stars and bright galaxies and then filtering the images at different scales to identify faint, extended sources.

Corvus A was first identified in earlier imaging surveys by the Dark Energy Spectroscopic Instrument (DESI). Recently, a team of astronomers led by Michael G. Jones of the University of Arizona in Tucson made follow-up observations of this object using instruments such as the Magellan Clay telescope or the Karl G. Jansky Very Large Array (VLA), which allowed them to confirm the low-mass status of the galaxy for Corvus A.

“Corvus A is a newly discovered low-mass galaxy identified during the initial phase of the SEAMLESS project,” the researchers wrote.

The observations found that the star body Corvus A has an irregular structure, and its light is dominated by a region of young blue stars on its eastern side. Astronomers have therefore pointed out that its blue, lumpy and irregular appearance is reminiscent of Leo P – a small star-forming irregular galaxy in the constellation Leo, one of the least massive in the Local Group, as its stellar mass is estimated to be around 560,000 solar masses.

According to the article, Corvus A, with a half-light radius of 834 light-years, is only a few times more massive than Leo P and contains many young stars whose ages do not exceed 200 million years. The study found that Corvus A is a gas-rich galaxy without regions of ionized interstellar atomic hydrogen – the so-called H II regions.

The distance to Corvus A was measured to be about 11.3 million light years. It also turns out that there are no other galaxies within about 3.3 million light-years of Corvus A, making it a remarkably isolated galaxy.

Astronomers noted that Corvus A’s proximity makes it an excellent target for follow-up, higher-resolution observations at both radio and optical wavelengths, which could shed more light on the kinematics of this newly discovered low-mass galaxy.

“With higher spectral and spatial resolution data (e.g. from MeerKAT or additional VLA configurations), it should be possible to both disentangle extension from warm and cold neutral media and to distinguish contributions from turbulence and rotation, when it may be possible to fit the kinematic model and determine rotation speed, if the slope is not too small,” the authors of the article conclude.

© 2024 Science X Network