Toothpaste fluorine formed in stars

Aug 21, 2014
The Sun by the Atmospheric Imaging Assembly of NASA's Solar Dynamics Observatory. Credit: NASA

The fluorine that is found in products such as toothpaste was likely formed billions of years ago in now dead stars of the same type as our sun. This has been shown by astronomers at Lund University in Sweden, together with colleagues from Ireland and the USA.

Fluorine can be found in everyday products such as toothpaste and chewing gum. However, the origins of the chemical element have been somewhat of a mystery. There have been three main theories about where it was created. The findings now presented support the theory that fluorine is formed in similar to the but heavier, towards the end of their existence. The sun and the planets in our solar system have then been formed out of material from these .

"So, the fluorine in our toothpaste originates from the sun's dead ancestors", said Nils Ryde, a reader in astronomy at Lund University.

With doctoral student Henrik Jönsson and colleagues from Ireland and the US, he has studied stars formed at different points in the history of the universe to see if the amount of fluorine they contain agrees with the predictions of the theory.

By analysing the light emitted by a star, it is possible to calculate how much of different elements it contains. Light of a certain wavelength indicates a certain element. In the present study, the researchers used a telescope on Hawaii and a new type of instrument that is sensitive to light with a wavelength in the middle of the infrared spectrum. It is in this area that the signal is found in this case.

"Constructing instruments that can measure infrared light with high resolution is very complicated and they have only recently become available", said Nils Ryde.

Different chemical elements are formed at high pressure and temperature inside a star. Fluorine is formed towards the end of the star's life, when it has expanded to become what is known as a red giant. The fluorine then moves to the outer parts of the star. After that, the star casts off the outer parts and forms a planetary nebula. The fluorine that is thrown out in this process mixes with the gas that surrounds the stars, known as the . New stars and planets are then formed from the interstellar medium. When the die, the interstellar medium is enriched once again.

The researchers are now also turning their attention to other types of stars. Among other things, they will try to find out whether fluorine could have been produced in the early universe, before the first red giants had formed. They will also use the same method to study environments in the universe that are different from the environment surrounding the sun, such as close to the at the centre of the Milky Way. There, the cycle of stars dying and new ones being born goes considerably faster than around the sun.

"By looking at the level of fluorine in the stars there, we can say whether the processes that form it are different", said Nils Ryde.

Explore further: Lives and deaths of sibling stars

Related Stories

Lives and deaths of sibling stars

Jul 23, 2014

This beautiful star cluster, NGC 3293, is found 8000 light-years from Earth in the constellation of Carina (The Keel). This cluster was first spotted by the French astronomer Nicolas-Louis de Lacaille in ...

Sun-like stars reveal their ages

Jul 10, 2014

(Phys.org) —Defining what makes a star "Sun-like" is as difficult as defining what makes a planet "Earth-like." A solar twin should have a temperature, mass, and spectral type similar to our Sun. We also ...

Recommended for you

What was here before the solar system?

May 29, 2015

The solar system is old. Like, dial-up-fax-machine-old. 4.6 billion years to be specific. The solar system has nothing on the universe. It's been around for 13.8 billion years, give or take a few hundred ...

Herschel's hunt for filaments in the Milky Way

May 29, 2015

Observations with ESA's Herschel space observatory have revealed that our Galaxy is threaded with filamentary structures on every length scale. From nearby clouds hosting tangles of filaments a few light-years ...

Sharp-eyed ALMA spots a flare on famous red giant star

May 29, 2015

Super-sharp observations with the telescope ALMA have revealed what seems to be a gigantic flare on the surface of Mira, one of the closest and most famous red giant stars in the sky. Activity like this in ...

NASA telescopes set limits on space-time quantum 'foam'

May 28, 2015

A team of scientists has used X-ray and gamma-ray observations of some of the most distant objects in the universe to better understand the nature of space and time. Their results set limits on the quantum ...

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

wkingmilw
not rated yet Aug 21, 2014
Deleted
supamark23
5 / 5 (2) Aug 21, 2014
Don't we use fluoride in toothpaste? Fluorine is a different animal


Fluoride is just the anion of fluorine.
Toiea
5 / 5 (2) Aug 21, 2014
So, the fluorine in our toothpaste originates from the sun's dead ancestors
Which element doesn't? We are star scavengers.

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

Click here to reset your password.
Sign in to get notified via email when new comments are made.