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xelasnave
30-11-2017, 02:15 PM
I cut this clipping out from Science Daily..
It seems rather exciting on a number of levels...

I am pressed for time and will get back with a link....

From Astronomy Daily and all credit to them...their article says...
First proper motions measured of stars in a small galaxy outside the Milky Way
Findings question models of dark matter halos
Date:
November 27, 2017
Source:
University of Groningen
Summary:
By combining data from the Hubble Space Telescope and the Gaia mission, astronomers have been able to measure the proper motion of 15 stars in the Sculptor Galaxy, the first such measurement outside the Milky Way. Analysis shows an unexpected preference in the direction of movement, which suggests that the standard theoretical models used to describe the motion of stars and dark matter halos in other galaxies might be invalid.

End.

That's part of it but I will get back to it..must go
Alex

xelasnave
30-11-2017, 02:20 PM
https://www.sciencedaily.com/releases/2017/11/171127124737.htm

Should do it..

xelasnave
30-11-2017, 02:22 PM
From the article

A second major result is a more precise measurement of the orbit of the Sculptor Galaxy around the Milky Way. 'This orbit is much wider than expected. Previously, it was believed that the current spheroidal shape of Sculptor was in part the result of some close passages, but our measurements show that this is not the case.'

Cool
Alex

xelasnave
30-11-2017, 03:44 PM
I wonder the measurments they had to make.
Alex

OICURMT
01-12-2017, 03:04 AM
http://astronomy.com/news/2017/11/astronomers-measure-the-motions-of-stars-in-a-nearby-galaxy

xelasnave
01-12-2017, 08:22 AM
Thanks
Alex

rally
01-12-2017, 01:24 PM
Try here for the actual paper

https://arxiv.org/pdf/1711.08945.pdf

xelasnave
01-12-2017, 04:08 PM
Thanks Rally.
Hope you are well.
Alex

Eratosthenes
03-12-2017, 10:46 AM
Using the motion of 15 stars in the Sculptor Galaxy is an insufficient data set to make generalised conclusions. How close were the 15 stars to one another? Are they gravitationally coupled? Is the Sculptor Galaxy special in any way? Is the region in which these stars reside special in any way? Who played the guitar lead on the Beetle's song "While my guitar gentle weeps"?

More data is required from many different types of Galaxies and using a randomised sample of stars within those galaxies.

Sounds interesting though,

xelasnave
03-12-2017, 11:14 AM
Hi Peter I hope you are well and thank you for your post.
I can't answer any of your question unfortunately.
Hopefully the research team will get further funding so they can gather more data.
Alex

mynameiscd
03-12-2017, 05:54 PM
I think it was Eric Clapton who played lead.
Not too sure about the motion of stars.