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Accueil > Seminar on 2021.03.01 by Eduardo (...) > The latest on the Great Attractor

The latest on the Great Attractor

Renée C. Kraan-Korteweg (Astronomy Department, Univ. of Cape Town)

I will give a brief overview of the current status of the mapping of
the Great Attractor (GA) mass overdensity which is mostly hidden from
our view by the Milky Way. We find that the combined results from
optical, NIR (FIR, X-ray) and in particular the systematic Parkes HI
surveys find the GA to consist of a nearby Great-Wall like structure
that crosses the Zone of Avoidance diagonally.

However, questions like "how massive is the GA really" and "who is
pulling in the Zone of Avoidance", the so-called GA versus Shapley
controversy, still remain unanswered. Because of this and following
the unexpected discovery of two galaxies at the most obscured part (20
mag in the optical) of the GA Wall with Spitzer and ATCA observations
we launched further infrared surveys. I will present the most recent
results on the GA Wall from a dedicated deep NIR survey across the
most opaque part of the Zone of Avoidance and its mass-density
estimate, as well as preliminary results from the flow-field derived
around the GA from a NIR Tully-Fisher analysis of HI detected galaxies
in the ZOA. If time permits I will hint at some of tug-and-war in this
area that is happening at even larger distances and how future SKA
Pathfinder HI surveys may resolve this controversy.

Présentation