Newswise — Thirty years after scientists at the University of Missouri-Rolla and Grambling College discovered "strange" Xenon in meteorites, scientists from Japan and France are reporting the discovery of other strange elements left over from the birth of the solar system.
A 1976 study published in the journal Nature showed that strange Xenon, which is made in supernova explosions, is present within the composition of the Sun. Those findings by the UMR and Grambling team were largely dismissed. Now, in the March 31 issue of Nature, the Japanese and French team reports new evidence that the Sun has strange Oxygen, too.
"Elements are called 'strange' when the mix of atoms that comprise the element is unlike the mix of atoms that make up that element here on Earth," explains UMR nuclear chemistry professor Dr. Oliver Manuel, who believes our solar system was created in a supernova blast. "Strange Xenon contains Xenon-136, which is made by rapid neutron capture in a supernova. Likewise, strange Oxygen has Oxygen-16, which is made by fusion inside a massive star."
Manuel has been invited to speak at an international conference on new physics this summer in Dubna, Russia, where he plans to share his latest work with other scientists. Although most scientific colleagues don't subscribe to his hypothesis about the birth of the solar system, Manuel says several studies published recently are validating what he's believed since the early 1970s: that our sun is the remains of a massive star that exploded to create the current sun and its nine planets, including Earth.
"The decay of the radioactive elements made in that explosion still makes the insides of the Earth hot today," Manuel says.
In Russia, Manuel will explain in detail how he believes the Sun separates elements and masks its internal workings.
"Our sun is a huge plasma diffuser that sorts atoms by weight and moves light elements like hydrogen and helium to its surface," Manuel says.
In 1983, Manuel and a UMR graduate student, Golden Hwaung, studied the solar wind and discovered that 22 different types of atoms had been separated and that lightweight atoms moved to the surface of the Sun. Earlier this year, Manuel and co-authors reported in the Journal of Fusion Energy that an additional 72 atoms had been sorted in the same fashion. Together, the two studies span the entire weight range of the stable elements, according to Manuel.
"Although the surface of the Sun is made of lightweight elements, the data shows the seven most abundant elements inside the Sun are iron, oxygen, silicon, nickel, sulfur, magnesium and calcium," Manuel says. "The most abundant elements inside the Sun are the same elements that are abundant in ordinary meteorites and rocky planets."
In the 1983 study, Manuel and Hwaung predicted that Jupiter would contain strange Xenon from the outer layers of the supernova that produced the solar system. And, in 1998, a team of UMR undergraduate students advised by Manuel used data from the Galileo mission to show that strange Xenon is indeed dominant in the outer regions of the solar system.
At the birth of the solar system, Manuel says, heavy elements from deep within the supernova stayed close to the Sun and congregated to form terrestrial planets like Earth, while the light elements from the outer layers of the supernova formed the big gaseous planets like Jupiter.
So all of the mass in the solar system came from the same source, according to Manuel's model, but the elemental composition of a given planet and the amount of "strange" elements it trapped depends on its distance from the Sun.
Scientists have believed that fusion of hydrogen atoms must be the source of the Sun's energy since the first hydrogen bomb blast in the early 1950s. Therefore, it has been widely believed that the composition of the entire Sun must be mostly hydrogen. Manuel disagrees. He says hydrogen, a lightweight element, is naturally abundant at the Sun's surface, but he thinks heavy iron is the most abundant element inside the Sun.
While many scientists now admit that a supernova might have had something to do with the formation of the solar system, they're not ready to fully embrace Manuel's model.
Earlier this year, findings at Arizona State University suggested a nearby supernova must have injected radioactive isotopes into the interstellar cloud of light elements that is believed to have formed the solar system. Manuel says the supernova was closer than they think. Furthermore, he says, the solar system was born catastrophically " it didn't slowly evolve from an interstellar cloud.
Last spring, the Arizona State team detected another footprint of the supernova explosion when they found the decay product of Iron-60 in a meteorite that had circled the Sun for millions of years before landing on Earth. In a Science article, the team noted that Iron-60 can only be made in a supernova.
"All of the iron in the Sun and Earth was made with the radioactive Iron-60 near the supernova core," Manuel says.
Although new findings are lending a lot of credibility to the notion that a supernova had something to do with the formation of the solar system, Manuel and his students have been chasing and processing the evidence for decades. Back in 1971, UMR graduate student Mervet Boulos found the decay products of short-lived elements inside the Earth and published her findings in the journal Science.
"The short-lived elements are gone now," Manuel says, "but long-lived radioactive elements like uranium still survive. This is what keeps the insides of the Earth hot."
Cosmologists who study the origin of the universe and the natural laws that govern its behaviors are also interested in Manuel's work " because our sun is the only one close enough for detailed study, and, therefore, it serves as a model for all of the other stars in the cosmos.
Immediately after the Russian conference on new physics, Manuel has been invited to present a paper at the "First Crisis in Cosmology Conference" in Moncao, Portugal. There, Manuel will explain what his measurements imply for the internal workings of the Sun and other ordinary stars.
The sun's not yellow; it's chicken " Bob Dylan