A new class of extragalactic astronomical sources discovered in 2021, named odd radio circles (ORCs)1, are large rings of faint, diffuse radio continuum emission spanning approximately 1 arcminute on the sky. Galaxies at the centres of several ORCs have photometric redshifts of z ≃ 0.3–0.6, implying physical scales of several 100 kpc in diameter for the radio emission, the origin of which is unknown. Here we report spectroscopic data on an ORC including strong [O ii] emission tracing ionized gas in the central galaxy of ORC4 at z = 0.4512. The physical extent of the [O ii] emission is approximately 40 kpc in diameter, larger than expected for a typical early-type galaxy2 but an order of magnitude smaller than the large-scale radio continuum emission. We detect an approximately 200 km s−1 velocity gradient across the [O ii] nebula, as well as a high velocity dispersion of approximately 180 km s−1.
LOFAR Telescope Uncovers Hidden Planets
rtrfm.com.au - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from rtrfm.com.au Daily Mail and Mail on Sunday newspapers.
Epoch Times Australia Staff | The Epoch Times
theepochtimes.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from theepochtimes.com Daily Mail and Mail on Sunday newspapers.
Center for Astrophysics
A Hubble image of the M-dwarf star Proxima Centauri, our closest stellar neighbor about four light-years away. Proxima hosts two planets, and is known to actively flare. Astronomers studying the suitability for life evolving on exoplanets around M-dwarf stars have completed a multi-wavelength analysis of an extreme flare on Proxima Cen.
Hubble/ ESA/NAS
The prospects for life around low-mass, cool M-type stars have been extensively discussed because these stars are the most common ones in the galaxy, and they frequently host Earth-sized planets in their habitable zones (orbits where the surface temperatures can support liquid water). Unfortunately for the prospects of life, however, these stars also exhibit higher levels of stellar activity and flaring than do more massive, solar-type stars, and flares can gradually deplete a planet’s atmosphere of molecules needed for life. Moreover, these hostile conditions persist in some fashion throughout their lifeti