Astronomers utilizing the WHT Enhanced Space Velocity Explorer (WEAVE), a strong new instrument mounted on the William Herschel Telescope on La Palma, have detected an surprising, elongated construction of ionized iron contained in the well-known Ring Nebula.
A composite picture of the Ring Nebula constructed from 4 WEAVE/LIFU emission-line photographs. Picture credit score: Wesson et al., doi: 10.1093/mnras/staf2139.
The Ring Nebula is an archetypal planetary nebula about 2,000 light-years away within the constellation of Lyra.
In any other case referred to as Messier 57, M57 or NGC 6720, this nebula was discovered by the French astronomer Charles Messier whereas trying to find comets in January 1779.
Messier’s report of his impartial discovery of Comet Bode reached the French astronomer Antoine Darquier de Pellepoix two weeks later, who then independently rediscovered the Ring Nebula whereas following the comet.
The newly-discovered bar-shaped cloud of iron atoms matches contained in the inside layer of the elliptically formed nebula.
The cloud’s size is roughly 500 occasions that of Pluto’s orbit across the Solar and its mass of iron atoms is similar to the mass of Mars.
The cloud was found in observations obtained utilizing the Giant Integral Area Unit (LIFU) mode of the brand new WEAVE instrument on the Isaac Newton Group’s 4.2-m William Herschel Telescope.
“Though the Ring Nebula has been studied utilizing many various telescopes and devices, WEAVE has allowed us to watch it in a brand new method, offering a lot extra element than earlier than,” mentioned Dr. Roger Wesson, an astronomer at College School London and Cardiff College.
“By acquiring a spectrum constantly throughout the entire nebula, we will create photographs of the nebula at any wavelength and decide its chemical composition at any place.”
“Once we processed the info and scrolled via the photographs, one factor popped out as clear as something — this beforehand unknown ‘bar’ of ionized iron atoms, in the midst of the acquainted and iconic ring.”
The character of the iron ‘bar’ within the Ring Nebula is unclear.
There are two potential eventualities: the bar could reveal one thing new about how the ejection of the nebula by the mum or dad star progressed, or (extra intriguingly) the iron is perhaps an arc of plasma ensuing from the vaporization of a rocky planet caught up within the star’s earlier enlargement.
“We positively must know extra — significantly whether or not every other chemical components co-exist with the newly-detected iron, as this might most likely inform us the proper class of mannequin to pursue,” mentioned Professor Janet Drew, an astronomer at College School London.
“Proper now, we’re lacking this essential data.”
The findings have been printed at this time within the Month-to-month Notices of the Royal Astronomical Society.
_____
R. Wesson et al. 2026. WEAVE imaging spectroscopy of NGC 6720: an iron bar within the Ring. MNRAS 546 (1): staf2139; doi: 10.1093/mnras/staf2139
