Dark Matter Deficiency in Galaxy NGC 1052-DF2

Astronomers at the Indian Institute of Astrophysics (IIA) have investigated the unusual deficiency of dark matter in the galaxy NGC 1052-DF2, which challenges established models of galaxy formation.

Key Findings

• The galaxy NGC 1052-DF2 is reported to be lacking in dark matter, conflicting with standard galaxy formation models.
• Previous studies estimated the galaxy's total 'dynamical mass' to be less than 340 million solar masses, mostly contributed by stars.
• This mass is significantly lower compared to the expected dark matter contribution, which is contrary to galaxies like the Milky Way.
• Such findings raise questions about the formation of galaxies with minimal dark matter and the nature of dark matter itself.

Research Methodology

• Astronomer K. Aditya used stellar density as an input parameter to create models explaining the mass distribution in NGC 1052-DF2.
• The observed stellar velocity dispersion profile was used as a constraint in these models.
• Mass models with a "cuspy" dark matter halo were found comparable to models without dark matter.
• Cuspy dark matter halos could not consistently explain the observed velocity dispersion profiles.
• As a result, the possibility of a cuspy dark matter halo for NGC 1052-DF2 was ruled out.

Implications

The findings suggest the need for further investigation into galaxy formation processes and the nature of dark matter, challenging existing paradigms and potentially offering new insights into astrophysical phenomena.