From Harvard University via Science Alert(AU): “Ancient Earth Really Was a Serene Water World New Evidence Confirms”

From Harvard University

via

ScienceAlert

Science Alert(AU)

11 MARCH 2021
MICHELLE STARR

1
Credit: WIN-Initiative/Getty Images.

It’s tricky to figure out what Earth might have looked like in the early years before life emerged. Geological detectives have now obtained more evidence that it was rather different to the planet we live on today.

According to a new analysis of the features of Earth’s mantle over its long history our whole world was once engulfed by a vast ocean with very few or no land masses at all. It was an extremely soggy space rock.

So where the heck did all the water go? According to a team of researchers led by planetary scientist Junjie Dong of Harvard University minerals deep inside the mantle slowly drunk up ancient Earth’s oceans to leave what we have today.

“We calculated the water storage capacity in Earth’s solid mantle as a function of mantle temperature,” the researchers wrote in their paper [below].

“The mantle’s water storage capacity today is 1.86 to 4.41 times the modern surface ocean mass.”

If the water stored in the mantle today is greater than its storage capacity in the Archean Eon, between 2.5 and 4 billion years ago, it’s possible that the world was flooded and the continents swamped, the researchers found.

This finding is in agreement with a previous study [Nature Geoscience] that found, based on an abundance of certain isotopes of oxygen preserved in a geological record of the early ocean, that Earth 3.2 billion years ago had way less land than it does today.

If this is the case, it could help us answer burning questions about other aspects of Earth’s history, such as where life emerged around 3.5 billion years ago. There’s an ongoing debate over whether life first formed in saltwater oceans or freshwater ponds on land masses; if the entire planet was engulfed by oceans, that would solve that mystery.

Furthermore, the findings could also help us in the search for extraterrestrial life. Evidence suggests that ocean worlds are abundant in our Universe, so looking for signatures of these soggy planets could help us identify potentially hospitable worlds. And it could strengthen the case for looking for life on ocean worlds in our own Solar System, such as Europa and Enceladus.

Not least, it helps us better understand the delicate evolution of our planet, and the strange, often seemingly inhospitable turns along the way that eventually led to the emergence of humanity.

The research has been published in AGU Advances.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

Harvard University campus

Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Established in 1636 and named for its first benefactor, clergyman John Harvard, Harvard is the oldest institution of higher learning in the United States and among the most prestigious in the world.

The Massachusetts colonial legislature, the General Court, authorized Harvard’s founding. In its early years, Harvard College primarily trained Congregational and Unitarian clergy, although it has never been formally affiliated with any denomination. Its curriculum and student body were gradually secularized during the 18th century, and by the 19th century, Harvard had emerged as the central cultural establishment among the Boston elite. Following the American Civil War, President Charles William Eliot’s long tenure (1869–1909) transformed the college and affiliated professional schools into a modern research university; Harvard became a founding member of the Association of American Universities in 1900.[10] James B. Conant led the university through the Great Depression and World War II; he liberalized admissions after the war.

The university is composed of ten academic faculties plus the Radcliffe Institute for Advanced Study. Arts and Sciences offers study in a wide range of academic disciplines for undergraduates and for graduates, while the other faculties offer only graduate degrees, mostly professional. Harvard has three main campuses: the 209-acre (85 ha) Cambridge campus centered on Harvard Yard; an adjoining campus immediately across the Charles River in the Allston neighborhood of Boston; and the medical campus in Boston’s Longwood Medical Area. Harvard’s endowment is valued at $41.9 billion, making it the largest of any academic institution. Endowment income helps enable the undergraduate college to admit students regardless of financial need and provide generous financial aid with no loans The Harvard Library is the world’s largest academic library system, comprising 79 individual libraries holding about 20.4 million items.

Harvard has more alumni, faculty, and researchers who have won Nobel Prizes (161) and Fields Medals (18) than any other university in the world and more alumni who have been members of the U.S. Congress, MacArthur Fellows, Rhodes Scholars (375), and Marshall Scholars (255) than any other university in the United States. Its alumni also include eight U.S. presidents and 188 living billionaires, the most of any university. Fourteen Turing Award laureates have been Harvard affiliates. Students and alumni have also won 10 Academy Awards, 48 Pulitzer Prizes, and 108 Olympic medals (46 gold), and they have founded many notable companies.

Colonial

Harvard was established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. In 1638, it acquired British North America’s first known printing press. In 1639, it was named Harvard College after deceased clergyman John Harvard, an alumnus of the University of Cambridge(UK) who had left the school £779 and his library of some 400 volumes.[22] The charter creating the Harvard Corporation was granted in 1650.

A 1643 publication gave the school’s purpose as “to advance learning and perpetuate it to posterity, dreading to leave an illiterate ministry to the churches when our present ministers shall lie in the dust.” It trained many Puritan ministers in its early years and offered a classic curriculum based on the English university model‍—‌many leaders in the colony had attended the University of Cambridge‍—‌but conformed to the tenets of Puritanism. Harvard has never affiliated with any particular denomination, though many of its earliest graduates went on to become clergymen in Congregational and Unitarian churches.

Increase Mather served as president from 1681 to 1701. In 1708, John Leverett became the first president who was not also a clergyman, marking a turning of the college away from Puritanism and toward intellectual independence.

19th century

In the 19th century, Enlightenment ideas of reason and free will were widespread among Congregational ministers, putting those ministers and their congregations in tension with more traditionalist, Calvinist parties. When Hollis Professor of Divinity David Tappan died in 1803 and President Joseph Willard died a year later, a struggle broke out over their replacements. Henry Ware was elected to the Hollis chair in 1805, and the liberal Samuel Webber was appointed to the presidency two years later, signaling the shift from the dominance of traditional ideas at Harvard to the dominance of liberal, Arminian ideas.

Charles William Eliot, president 1869–1909, eliminated the favored position of Christianity from the curriculum while opening it to student self-direction. Though Eliot was the crucial figure in the secularization of American higher education, he was motivated not by a desire to secularize education but by Transcendentalist Unitarian convictions influenced by William Ellery Channing and Ralph Waldo Emerson.

20th century

In the 20th century, Harvard’s reputation grew as a burgeoning endowment and prominent professors expanded the university’s scope. Rapid enrollment growth continued as new graduate schools were begun and the undergraduate college expanded. Radcliffe College, established in 1879 as the female counterpart of Harvard College, became one of the most prominent schools for women in the United States. Harvard became a founding member of the Association of American Universities in 1900.

The student body in the early decades of the century was predominantly “old-stock, high-status Protestants, especially Episcopalians, Congregationalists, and Presbyterians.” A 1923 proposal by President A. Lawrence Lowell that Jews be limited to 15% of undergraduates was rejected, but Lowell did ban blacks from freshman dormitories.

President James B. Conant reinvigorated creative scholarship to guarantee Harvard’s preeminence among research institutions. He saw higher education as a vehicle of opportunity for the talented rather than an entitlement for the wealthy, so Conant devised programs to identify, recruit, and support talented youth. In 1943, he asked the faculty to make a definitive statement about what general education ought to be, at the secondary as well as at the college level. The resulting Report, published in 1945, was one of the most influential manifestos in 20th century American education.

Between 1945 and 1960, admissions were opened up to bring in a more diverse group of students. No longer drawing mostly from select New England prep schools, the undergraduate college became accessible to striving middle class students from public schools; many more Jews and Catholics were admitted, but few blacks, Hispanics, or Asians. Throughout the rest of the 20th century, Harvard became more diverse.

Harvard’s graduate schools began admitting women in small numbers in the late 19th century. During World War II, students at Radcliffe College (which since 1879 had been paying Harvard professors to repeat their lectures for women) began attending Harvard classes alongside men. Women were first admitted to the medical school in 1945. Since 1971, Harvard has controlled essentially all aspects of undergraduate admission, instruction, and housing for Radcliffe women. In 1999, Radcliffe was formally merged into Harvard.

21st century

Drew Gilpin Faust, previously the dean of the Radcliffe Institute for Advanced Study, became Harvard’s first woman president on July 1, 2007. She was succeeded by Lawrence Bacow on July 1, 2018.