An image of Hubble space telescope in orbit (Image source: NASA)
The latest ESA/Hubble Picture of the Week features a strikingly bright galaxy called Markarian 178 (Mrk 178). The galaxy is loaded with numerous young, hot stars. But even more interesting is the presence of a rare class of stars called Wolf-Rayet stars.
Markarian 178 (Mrk 178) is a dwarf galaxy. This means that it is much smaller than our Milky Way. Mrk 178 lies 13 million light-years away in the constellation Ursa Major (The Great Bear). Like other Markarian galaxies, Mrk 178 is remarkably bright when viewed in ultraviolet light.
In this Hubble observation, Mrk 178 appears as a blue compact galaxy in a black background. The blue color indicates that there are countless young hot stars within the galaxy. But the galaxy is not all blue. There’s a red-colored appearance that is more concentrated towards the edge of the galaxy. This reddish appearance is formed due to the presence of a rare class of stars called Wolf-Rayet stars.
Wolf-Rayet stars are extremely massive and extremely hot stars that only last a few million years. These stars are in the final stage of their lives before they explode as supernovae and become a neutron star or black hole. The stars blast away their outer layers into space using strong stellar winds. The strong emissions from the Wolf-Rayet stars ionize the surrounding hydrogen gas, producing the observed red light.
The fact that Wolf-Rayet stars last only a few million years means that something must have triggered the recent burst of star formation. Deeper images from the Large Binocular Telescope revealed faint tidal features around the galaxy. These tidal features suggest that a smaller satellite galaxy in the past might have triggered the recent star formation in Mrk 178.
Future Hubble observations of this galaxy will help astronomers study how star formation exactly happened in Mrk 178.
Hubble image of Markarian 178 (Image source: ESA/Hubble, NASA, F. Annibali, and S. Hong)
Chibuike Okpara – Tech Writer – 313 articles published on Notebookcheck since 2024
I have always been fascinated by technology and digital devices my entire life and even got addicted to it. I have always marveled at the intricacy of even the simplest digital devices and systems around us. I have been writing and publishing articles online for about 6 years now, just about a year ago, I found myself lost in the marvel of smartphones and laptops we have in our hands every day. I developed a passion for learning about new devices and technologies that come with them and at some point, I asked myself, “Why not get into writing tech articles?” It is useless to say I followed up the idea — it is evident. I am an open-minded individual who derives an infinite amount of joy from researching and discovering new information, I believe there is so much to learn and such a short life to live, so I put my time to good use — learning new things. I am a ‘bookworm’ of the internet and digital devices. When I am not writing, you will find me on my devices still, I do explore and admire the beauty of nature and creatures. I am a fast learner and quickly adapt to changes, always looking forward to new adventures.
Chibuike Okpara, 2025-12- 8 (Update: 2025-12- 8)
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