Astro Group Project

Keep up with what the 5 different research groups are doing and what they discover for the first year of the Observational Astrophysics group project (PHYS369). Here you can also find the fantastic Result of the Week and a brief explanation.

LAMPSS: Results of the week:

WARP discoveries of the week:

A colour-map showing the correspondence between colour-colour and metallicity and the real stars (with errors) over-plotted.

Our first colour-colour grid produced by convolving the spectra of stars of different spectral types and different metallicities. This allows us to read off a metallicity given an observed combination of colours for a real star.

WARP was able to obtain a way to separate between galaxies and stars using their redshift first, and then using a combination of optical and near-infrared colours. The axes are magnitude differences which showed the clearest division of galaxies and stars.

We were also able to make colour predictions for different spectral types with different metallicities which we will use to interpret our data:

SNAG discoveries of the week

Galactic Filaments. Upon reducing our data set by limiting the redshift to a narrow band we were left with a cross section of space at a given distance from Earth. Zooming into this cross section we can see a web like structure, with areas of high density and areas of low density. The high density strings are known as galactic filaments.

Galactic Filaments are thought to be caused by filaments of dark matter that stretch across the universe, forming an entangled web. Although we cannot currently detect dark matter, we believe that it interacts with conventional matter via gravity. These dense regions of dark matter have a stronger gravitational force attracting nearby galaxies which ultimately pulls them into the same filament pattern.

Filaments typically range in size from 50 to 80 megaparsecs, making them the largest known structures in the universe. Will SNAG uncover the mystery of dark matter and why it causes galaxies to conform to these filament patters? It’s unlikely, but we are excited to see where our project goes from here.

SHREDS discovery of the week #1: