Newton

Our solar system officially houses eight planets, but some scientists say there could be a ninth hiding on the fringes. Now, a new study has found the oddities could be explained by modified theories of gravity, an alternative idea to dark matter.

Astrophysicists have observed puzzling behavior in star clusters that defies our current understanding of gravity at cosmic scales. Intriguingly, the observations fit with an alternative theory of gravity that could negate the need for dark matter.

One of the most valuable scientific documents in history changed hands this week, when an autographed Isaac Newton manuscript of revisions to the first edition of the Philosophiae Naturalis Principia Mathematica sold at Christie's for £1,702,500.

The final round of scientific auctions for 2017 occurred last week and there were the usual puzzling results in a market slightly off the boil. There were some rare scientific documents and instruments to be had at reasonable prices that will return a handsome profit in the short to medium term.

A $500,000 farm-find Aston Martin DB4, a $3.7 million copy of Newton's "Principia," a Hendrix acoustic guitar that sold for $260,000 and the only remaining Indian-Vincent prototype from 1949 are the highlights of this week's auction report.

Bonhams annual History of Science and Technology sale is a regular feature on the auction calendar and this year it will be held on December 7 with another treasure trove of significant artifacts of humanity's scientific heritage.

This installment of our top 50 scientific documents moves into heavyweight territory with Isaac Newton's "Principia Mathematica", "De revolutionibus orbium coelestium" by Nicolaus Copernicus, the Archimedes Palimpsest, and Einstein's letter to Franklin D Roosevelt that catalyzed nuclear warfare.

From the rare scribblings of Alan Turing through to the genius of Newton, Einstein and Émilie du Châtelet​, we continue to navigate our way through the fascinating list of the 50 most valuable scientific documents of all-time​.

A close look at the world's most valuable scientific documents and manuscripts illustrates both how far science has come in a relatively short time, and how little we value our legacy in monetary terms.

Researchers with the Lawrence Berkeley National Laboratory and the University of California Berkeley have measured what is believed to be the smallest force yet recorded – 42 yoctonewtons, or a septillionth of a newton.