Giant ELT Telescope Could Weigh Dark Matter in Ultra-Diffuse Galaxies

Some galaxies are so faint and spread out that astronomers struggle to weigh them, and a new proposal says Europe's giant telescope could help. Universe Today reports a paper in New Astronomy, led by PhD student Marco Mirabile of INAF and the Gran Sasso Science Institute in Italy, suggesting a new instrument for the Extremely Large Telescope.

The concept, called NEXUS@SHARP, would be a near-infrared multi-slit spectrograph able to observe many faint globular clusters at once. That would then allow two independent mass measurements of ultra-diffuse galaxies, a comparison that could help distinguish between competing formation scenarios and test the Lambda-CDM model of how the universe works.

It is important to note this is a concept study rather than an observational discovery, and the paper argues for the instrument to be built rather than announcing results. Still, it clearly shows how next-generation giant telescopes could tackle the dark matter mysteries hidden deep inside these faint ghostly galaxies.