Observatory Logo

From: TerryMosel@aol.com
Date: 15 March 2007 01:30:46 GMT
To: iaa2000@btinternet.com
Subject: Lectures in UCD & N.I., LIGHT POLLUTION Sky survey

Hi all,


Astronomy seminar to be held in UCD: Title: Massive Star Formation along
the Hubble Sequence Speaker: Prof. Nicholas Devereux, Fulbright scholar,
NUI Galway Date: Thursday, March 15th, 2007 Time: 3.30pm Room: 128 UCD
School of Physics, Science Centre North, Belfield Tea afterwards in the
common room All welcome

Abstract: New results, based on one of the most comprehensive H-alpha
imaging surveys of nearby Sa-Sab spirals completed to date, reveals
early-type spirals to be a diverse group of galaxies that span a wide
range in massive star formation rates. While the majority of Sa-Sab
galaxies in our sample are forming stars at a modest rate, a significant
fraction (~29%) exhibit star formation rates greater than 1 Msolar yr-1,
rivaling the most prolifically star-forming late-type spirals. A similar
diversity is apparent in the star formation history of Sa-Sab spirals as
measured by their H-alpha equivalent widths. Consistent with our
preliminary results presented in the first paper in this series, we find
giant H II regions [L(H?)>=10^39 ergs s-1] in the disks of ~37% of
early-type spirals. We suspect that recent minor mergers or past
interactions are responsible for the elevated levels of H-alpha emission
and, perhaps, for the presence of giant H II regions in these galaxies.
Our results, how ever, are not in total agreement with the H-alpha study
of Kennicutt & Kent, who did not find any early-type spirals with
H-alpha equivalent widths >14Å A close examination of the
morphological classification of galaxies, however, suggests that
systematic differences between the Revised Shapley-Ames Catalog and the
Second Reference Catalogue may be responsible for the contrasting

2. LECTURES BY JERRY STONE: (message from Pat O'Neill) "See attached
schedule of talks by Jerry Stone. I was at his talk in Queen's. He is a
very good speaker and certainly knows his stuff, excellent value for a
£5-00. The talk lasted for 2 and a quarter hrs! Terry, Can you
broadcast on your circulation list? You can also get more info by
'Googling' him. Regards, Pat"

3. LIGHT POLLUTION SURVEY: (From Al White): "The 'Globe At Night' survey
is running until 21 March. This is a survey designed to record the
limiting magnitude of the night sky across the world. If you could pass
this on to your mailing list perhaps people could report their

More info can be found at the following links here.
Also here: here.

Cheers, ~Albert
Albert White BSc. FRAS Chairperson,
International Dark Sky Association - Irish Section 

 Clear Skies,

Terry Moseley


Last Revised: 2007 March 15th
Go to HOME PageHome Page