Go Back   IceInSpace > General Astronomy > Astronomy and Amateur Science

Reply
 
Thread Tools Rate Thread
  #1  
Old 15-02-2020, 06:04 AM
Weltevreden SA's Avatar
Weltevreden SA (Dana)
Dana in SA

Weltevreden SA is offline
 
Join Date: Apr 2012
Location: Nieu Bethesda, Karoo, South Africa
Posts: 216
Anyone following the news about the Radcliffe Wave?

Hi all, there has been a spate of very recent papers about an object dubbed the Radcliffe Wave. It is a "Nessie" type of long, skinny dark dust/gas filament that is several hundred pc long lying just outside of the Solar radius It appears to align with the outer side of the Local Arm. The Radcliffe Wave is a structure found embedded inside the dust filament is is as stretched out while being skinny as the filament itself The unusual name comes from the fact that the Wave that has a huge vertical sine-wave warp in it, even though it is straight-arrow along its length. There are several papers devoted to the Wave and the filament-like structure in which the Wave resides.


The giant in our stars <https://news.harvard.edu/gazette/sto...is-discovered/>
Alves-Zucker-Goodman 2019, A Galactic-scale gas wave in the Solar neighborhood <https://arxiv.org/abs/2001.08748>

Klessen et al 2019, The Dust Factory. <https://arxiv.org/pdf/1911.05753.pdf>



The discovery and ancillary papers focus on gas/dust kinetics, spiral arm shear & torsion, and gravitational compression, but leave electromagnetic fields (magnetohydrodynamics or MHD) out of it. A pity because to me, the Wave looks suspiciously like a magnetic flux tube or a Birkeland current running lengthwise down the filament. If that is the case, it would explain some physics that we are still somewhat unclear about—metallicity distribution towards the Galactic centre for one. When you read into the supplementary web links on the group page related to this Wave, it is clear that the Wave's larger host filament is one of those dark thready filaments we see next to and co-linear with spiral arms. We see these things all the time in astro images (less often visually, e.g., the M31 dark streaks). I have till now been so fascinated by the H2 regions and starbursts that I didn't pay much mind to the dark streaks in there. Now, from these recent papers it appears that the professionals have begun to study along the lengths of these things instead of the typical preoccupation with compression fronts into a spiral wave.



This is quite an interesting development because it explains physics we don't fully understand — metallicity distribution, gas-star migration toward the center of galaxies due to spiral arm passages, and the presence of so many spurs, short arms, and flat arms (M101) in galaxy outer regions. Put in simpler terms, there's a lot of news yet to come out of these faint fuzzballs spinning in the sky. Whether backyard at the eyepiece or riffling through the ADS papers, there's a lot out there to keep us looking.


=Dana IN S Africa
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 08:17 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement