Miss­ing iron found in in­ter­stel­lar space

Astronomer­s find traces of a heavy element they have been hunt­ing for years

Sky at Night Magazine - - BULLETIN -

Huge amounts of ‘miss­ing’ iron, which astronomer­s have been look­ing for for decades, could be hid­ing in plain sight in the space be­tween stars, ac­cord­ing to a new study.

Iron is one of the most abun­dant heavy el­e­ments in the Uni­verse and is com­monly found around stars. How­ever, when astronomer­s pull back to look at in­ter­stel­lar space, there seems to be hardly any.

This doesn’t nec­es­sar­ily mean that there is no iron in in­ter­stel­lar space, only that it’s in a form we can’t de­tect. The iden­tity of this exotic form of iron has evaded astronomer­s for decades. Now, a team from Ari­zona State Univer­sity (ASU) might have found the cul­prit – clumps of iron atoms bonded onto chains of car­bon atoms known as iron pseu­do­car­bynes.

“We are propos­ing a new class of mol­e­cules that are likely to be wide­spread in the in­ter­stel­lar medium,” said Pi­larisetty Tarakesh­war, from ASU who led the study.

Astronomer­s know that clumps of iron atoms ex­ist in space from look­ing at me­te­orites. Mean­while, ob­ser­va­tions of in­ter­stel­lar space show that long chains of car­bon atoms are found through­out the cos­mos. The team dis­cov­ered that in the deep freeze of space th­ese two el­e­ments stick to­gether, form­ing very dif­fer­ent mol­e­cules than they would in the warm en­vi­ron­ment near a star.

“We cal­cu­lated what the spec­tra of th­ese mol­e­cules would ac­tu­ally look like, and we found that they have spec­tro­scopic sig­na­tures nearly iden­ti­cal to car­bon-chain mol­e­cules with­out any iron,” says Tarakesh­war.

The find could ex­plain why the iron has gone un­no­ticed for so long – it blends into the back­ground of th­ese car­bon chains. “Pre­vi­ous astro­phys­i­cal ob­ser­va­tions could have over­looked th­ese car­bon-plus­iron mol­e­cules,” says Tarakesh­war.

The dis­cov­ery could also ex­plain an­other long-stand­ing puz­zle. De­spite the fact that any car­bon chain over nine atoms long should be un­sta­ble and fall apart, astronomer­s reg­u­larly ob­serve chains much longer than this limit. It could be that th­ese long chains are created by iron atoms weld­ing shorter chains to­gether.

“Our work pro­vides new in­sights into bridg­ing the yawn­ing gap be­tween mol­e­cules containing nine or fewer car­bon atoms and com­plex mol­e­cules such as C60 buck­min­ster­fullerene, bet­ter known as buck­y­balls,” says ASU’s Frank Timmes. https://asunow.asu.edu

Com­plex car­bon mol­e­cules may form in space with the help of clus­tered iron atoms

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.