Study confirms that stellar novae are the main source of lithium in the universe

Study confirms that stellar novae are the main source of lithium in the universe
Artist's concept of a binary system similar to the one that originated the nova Sagittarii 2015 N.2. Credit: David A. Hardy y PPARC

Lithium, the lightest solid element, is created during astrophysical phenomena, but its origin has been elusive. Recently, a group of researchers detected enormous quantities of beryllium-7, an unstable element that decays into lithium in 53.2 days, inside nova Sagittarii 2015 N.2, which suggests that novae are the main source of lithium in the galaxy.

Practically every chemical element has an astronomical origin. Light elements were formed between 10 seconds and 20 minutes after the Big Bang, including (75%), helium (25%) and a very small amount of lithium and beryllium.

The remaining were formed in stars, either through fusion of other elements inside the nucleus, which begins with the fusion of hydrogen into helium, and produces increasingly heavy elements until iron forms. Other processes such as supernovae explosions or reactions in the atmospheres of giant stars produce gold, lead and copper, among others. Those elements were in turn recycled into new stars and planets, until the present time.

Luca Izzo, researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC), says, "But lithium posed a problem: We knew that 25 percent of existing lithium comes from primordial nucleosynthesis, but we were not able to trace the origins of the remaining 75 percent."

Solution to the lithium enigma

The solution to the enigma of the origin of lithium lies, according to this study, in the novae, explosive phenomena occurring in binary star systems in which one of the stars is a white dwarf. The white dwarf can nab material from its twin star and form a superficial layer of hydrogen which, when it reaches a certain density, will trigger a nova, which can increase the brightness of the star up to 100 thousand times. After a few weeks, the system stabilizes and the process starts again.

Study confirms that stellar novae are the main source of lithium in the universe
Credit: Instituto de Astrofísica de Andalucía

The researchers studied nova Sagittarii 1015 N.2 (also known as V5668 Sgr), which was detected on March 15th, 2015, and remained visible for more than 80 days. The observation, made with the UVES instrument of the Very Large Telescope (ESO) in the course of 24 days, made it possible for the first time to follow the evolution of the beryllium-7 signal inside a nova and to calculate the amount present. "Beryllium-7 is an unstable element that decays into lithium in 53.2 days, so its presence is an unequivocal sign of the existence of lithium," says Christina Thöne, researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC).

The existence of beryllium-7 had been previously documented in another nova, but the measurement of the amount of lithium produced from nova Sagittarii 1015 N.2 came as a surprise. "We're talking about an amount of lithium 10 times greater than that in the sun," says Luca Izzo (IAA-CSIC). "With these amounts in mind, two similar a year would suffice to account for all the lithium in the Milky Way. Novae seem to be the predominant source of in the universe," he concludes.


Explore further

First detection of lithium from an exploding star

More information: P. Molaro et al. Highly enriched 7Be in the ejecta of Nova Sagittarii 2015 No. 2 (V5668 Sgr) and the Galactic 7Li origin, Monthly Notices of the Royal Astronomical Society: Letters (2016). DOI: 10.1093/mnrasl/slw169
Provided by Instituto de Astrofísica de Andalucía
Citation: Study confirms that stellar novae are the main source of lithium in the universe (2016, November 3) retrieved 16 September 2019 from https://phys.org/news/2016-11-stellar-novae-main-source-lithium.html
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Nov 03, 2016
"With these amounts in mind, two similar novae a year would suffice to account for all the lithium in the Milky Way. Novae seem to be the predominant source of lithium in the universe," he concludes.

So why not conclude that novae also account for the fabled 25% 'known' to be from the Huge Bang as well?? Answer: Because the author is another committed Merger Maniac!

Nov 03, 2016
Yay ! That seems to be that for the 'Primordial Lithium Anomaly'...

Nov 03, 2016
Given that it takes the mind boggling energy of merging neutron stars to produce the heavier elements I find it puzzling that the even greater energy of the early universe only produced Hydrogen and Helium.

Nov 03, 2016
Given that it takes the mind boggling energy of merging neutron stars to produce the heavier elements I find it puzzling that the even greater energy of the early universe only produced Hydrogen and Helium.

Who said anything about merging neutron stars?!?
And to answer the 2nd part of your comment - Hydrogen and Helium had to be formed FIRST....

Nov 03, 2016
So this is a mechanism to produce massive amounts of lithium without resorting to the big bang explanation, is that correct? Lithium is not just from the early universe, as predicted, its spread out everywhere. Couldn't this mechanism account for all of the lithium in the universe? I thought that there were observations of white dwarfs in the very distant universe as well...

Nov 04, 2016
@tb... It *would* have produced lots of lithium, but most of that quickly broke down under those hyper-hot conditions. Hence the 'primordial anomaly'.

@Wulf, IIRC, the problem was that there's too much lithium about for all of it to be 'primordial'. Something, some-where in recent universe was brewing the stuff. Now we know where a lot of it is coming from, the next stage must be to figure the precise pathway of the synthesis...

Nov 05, 2016
Hi everyone. :)

Lithium etc 'abundances' was never a 'problem' until 'creationist' BB-Hypothesis 'created' said 'problem'; because of 'ad hoc' BB assumptions/interpretations re observed phenomena.

Those ad hoc assumptions/interpretations now increasingly exposed as simplistic, naive, biased towards BB-scenarios rather than being treated via objective/alternative scenarios that did not include 'creationist' BB scenarios.

Add this latest dispelling, of a BB-created 'problem', to all the other BB-created 'furphies' also being increasingly dispelled by new mainstreamer observations/reviews, and you see the trend: the BB-related 'problems', 'interpretations' etc have had their shot....and missed all that reality which owes nothing to any naively/wrongly-hypothesized 'one-time', 'ex-nihilo', 'universal creationist' BB 'event'.

Good to see mainstream getting its observational/interpretational/analysis act together, without all those past philosophical/metaphysical biases.

Nov 06, 2016
interested scientist may like to know. our information show, detected elements in stars emission are mostly secondhand. MG1

Nov 06, 2016
This will no doubt disappoint a lot of people, I know it disappointed me at least, but the find does little to alleviate the 7Li problem. The reason is [of course! \ slaps head) that the BB element background is observed in ancestral PopII stars, not the current generation stars in the Milky Way:

"The present measurement of helium-4 indicates good agreement, and yet better agreement for helium-3. But for lithium-7, there is a significant discrepancy between BBN and WMAP/Planck, and the abundance derived from Population II stars. The discrepancy is a factor of 2.4―4.3 below the theoretically predicted value and is considered a problem for the original models,[14] that have resulted in revised calculations of the standard BBN based on new nuclear data, and to various reevaluation proposals for primordial proton-proton nuclear reactions, especially the abundances of 7Be(n,p)7Li versus 7Be(d,p)8Be.[15]"

[ https://en.wikipe...ynthesis ]

Nov 06, 2016
So what does the paper [link in RNP comment] say on the observation in relation to BBN?

"However, a rate of 2 yr−1 of slow Nova events with the observed 7Li overproduction in a Galaxy lifetime of ≈ 10^10 yr is enough to produce MLi ≈ 140 MSolar. This is comparable with the MLi ≈ 150 MSolar estimated to be present in the Milky Way inclusive of the MLi ≈ 40 MSolar produced in the Big Bang (Fields, Molaro & Sarkar 2014). Thus, the slow Novae could indeed be the main factories of 7Li in the Galaxy."

So they come up 10 solar masses short, which BBN has to supply, roughly consistent with the 40 Msolar BBN 7Li observed. (I think, the reference discusses obs and estimates based on MW Pop II cluster stars.)

@f_darwin: Elements has to be secondhand products going back to the Big Bang emergence of "cold" (everyday) particles. [ https://en.wikipe...ynthesis ]

I am not sure who you refer to as "scientist", but astronomers know it.

Nov 09, 2016
@ torbjorn_b_g_larsson, RNP, Phys1, IMP-9, antialias et al. :)

Time to take stock of all implications of recent observational/revisional developments which increasingly militating against all Big Bang/related hypotheses, assumptions and interpretations built into the current literature/paradigm promulgated to date.

Please read... https://blogs.sci...nceive/#

Then view ALL of this...

http://vms.fnal.g...=1944338

And THEN add/recall my posts pointing out how CMB, Elemental Abundances (including Lithium), observed phenomena/features is easily, logically, REALITY-physically, explained via various scale accretion-disc-polar-jet systems/processes Eternally recycling/redistributing material/energy from/into deep space to produce observed variety of 'ages', 'abundances' and 'structures'.

BB scenarios fail to do any of that without ad hoc/unreal 'fixes' like Inflation/Expansion etc. :)

Nov 13, 2016
So they found this supernova within 52.5 days of its eruption? That is the only way I can interpret the article. If "beryllium-7, an unstable element that decays into lithium in 53.2 days" was found, vice large amounts of lithium, doesn't that imply that the SN happened within the last 52.5 days (I know it actually wasn't 52.5 days, but the article does not give a distance to the SN)? Am I getting this wrong or is it something else?

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