Astrophysicists measure key cosmic step in formation of early stars

Astrophysicists measure key cosmic step in formation of early stars
The white cross indicates the position of the massive protostar, while the red contours show emission from the shocked gas in the jets coming from the protostar. Credit: University College Dublin

Astrophysicists in Ireland have, for the first time, measured a crucial step in the formation and evolution of stars.

An international effort lead by UCD Ph.D. student Rubén Fedriani Lopez has recorded the total mass and energy from a jet driven by a high-mass protostar.

It is believed the cosmic birthing cries of these spiralling giants play a key role in the development of newly forming stars.

Stars are created in clouds of gas and dust, and early stars, or protostars, collect this gas with their gravitational pull.

As material condenses and a star begins to evolve, a portion gets ejected forming high-velocity jets which help redistribution this stellar outflow.

The team's findings suggest a common mechanism is in place in the formation of jets in low-mass and high-mass protostars.

Published in Nature Communications, the work was conducted by the star formation group from the Dublin Institute of Advanced Studies (DIAS) and University College Dublin.

"We are now one step closer to filling in the gap between low-mass and high-mass star formation, which is very significant," said Rubén, who is Ph.D. student at DIAS and UCD School of Physics.

"We are on the cutting edge of science in this area, and having access to the best telescopes in the world via Ireland's membership with the European Southern Observatory, and collaborating internationally has helped greatly in getting us there."

The UCD and DIAS researcher led an international team of astrophysicists from seven different institutions in six countries.

Alessio Caratti o Garatti, co-author of the study, added: "After many years of debate, we are finally understanding how massive form, namely accreting matter from discs, while at the same time ejecting powerful and highly collimated jets."

The team collected their data by making use of the Hubble Space Telescope, the Karl Jansky Very Large Array and from the Very Large Telescope at the European Southern Observatory.

The new discovery follows on from another major astronomical discovery by UCD physicists, who earlier this year helped redraw the map of the Universe by uncovering almost 300,000 previously unseen galaxies.


Explore further

Massive stars grow same way as light stars, just bigger

More information: R. Fedriani et al. Measuring the ionisation fraction in a jet from a massive protostar, Nature Communications (2019). DOI: 10.1038/s41467-019-11595-x
Journal information: Nature Communications

Citation: Astrophysicists measure key cosmic step in formation of early stars (2019, August 12) retrieved 21 September 2019 from https://phys.org/news/2019-08-astrophysicists-key-cosmic-formation-early.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
303 shares

Feedback to editors

User comments

Aug 12, 2019
@Castrogiovanni
@S_E_U.

From the above article:
As material condenses and a star begins to evolve, a portion gets ejected forming high-velocity jets which help redistribution this stellar outflow.

The team's findings suggest a common mechanism is in place in the formation of jets in low-mass and high-mass protostars.


Recall that is exactly what I was explaining to you re star formation 'nova stage' when polar jets/stellar winds are at their most extreme; ie:
...You may also not realise that at that violent/hot 'fusion initiating' stage/process, the newly formed star is also producing extreme POLAR JETS and EQUATORIAL MASS SEPARATIONS capable of reducing its erstwhile EXTREME ANGULAR MOMENTUM that would otherwise still be deforming the stellar body far from its 'settled' practically spherical shape....
...that was from my post to @S_E_U dated Jul 16, 2019 in thread...

https://phys.org/...ora.html

Cheers. :)

Aug 12, 2019
Recall that is exactly what I was explaining to you re star formation 'nova stage' when polar jets/stellar winds are at their most extreme; ie


There is no 'nova stage'. Jets from YSOs are a well known and predictable phenomenon.

Aug 12, 2019
Star formation is one of the least comprehended phenomenon in astrophysics. Is there a general theory of star formation? No, there is not. There is a number of models based on computer simulations which include supersonic hydrodynamics with non-ideal MHD turbulence influenced by gravity. They include the line and continuum radiative processes of the energy transfer; a number of chemical processes with dissociation, recombination and ionization, with uncertain nomenclature of atoms and molecules, unknown magnetic fields and formation and destruction of dust particles. In addition there is macrophysics that is an environment in the molecular clouds, clumps and cores; inclusion in the multiple systems, collisions among stellar systems; jets and outflows; radiation
https://www.acade...ormation

Aug 13, 2019
Hold on. Wait a moment, RC. YOUR post is directly underneath where it says User comments. You are somehow referencing ME in your post as though I had already posted a comment above yours - which I did not. This is verrrry strange, RC.

Aug 13, 2019
@S_E_U.
Hold on. Wait a moment, RC. YOUR post is directly underneath where it says User comments. You are somehow referencing ME in your post as though I had already posted a comment above yours - which I did not. This is verrrry strange, RC.
I should have put the link to the relevant thread at the start instead of at the end of my above post. My bad. :)

I was effectively continuing on from that other thread re our mutual exchanges re above subject matter. Here is that other thread's link again...

https://phys.org/...ora.html

...please see my relevant post to you therein, dated Jul 16, 2019. Thanks. :)


Aug 13, 2019
@Castrogiovanni.
Recall that is exactly what I was explaining to you re star formation 'nova stage' when polar jets/stellar winds are at their most extreme; ie


There is no 'nova stage'. Jets from YSOs are a well known and predictable phenomenon.
You are conflating the YSO pre-main-sequence phase with proper onset of New Star (or 'nova') main sequence phase when the new star blows off much of its obscuring surrounding circumstellar accretion material except for any material which has formed proto-planets/planets which survive to remain as the new star's evolving planetary system. Please understand that I use the 'generic' nova term for a newly-visible main-sequence-brightness star which has initiated main fusion and become much brighter and more visible from farther afield via the usual full spectrum of stellar EM radiations. Thanks. :)

Aug 13, 2019
There is no such thing as 'nova' phase. It is gibberish.

Aug 13, 2019
@Castrogiovanni.
There is no such thing as 'nova' phase. It is gibberish.
Nova as in 'new', mate. I explained all this before. What is it about 'new' and its Latin 'nova' as a generic term that you did not understand? :)

ps: While we're here, may I ask you why you are so evasive about the point I raised re the 'non-EM-interacting' matter going into BHs early on in BB timeline and so none should have survived that epoch? I explained that (as observed everywhere) ORDINARY EM-interacting' stuff is significantly retarded/ejected in/from polar-jets/disc-winds-producing Magnetic Field Patterns around BHs; whereas your allegedly-non-EM-interacting stuff is NOT retarded/ejected like that, and so would have ALL gone DIRECTLY into BHs EARLY ON if BB was correct and the density was as hypothesised, allowing direct-accretion into hyper-massive stars/BHs. The longer you evade that the more cowardly/dishonest you look in the eyes of the readers/your 'enemies' here. So address it now. :)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more