Letter Published: 25 April 2012 Impact spherules as a record of an ancient heavy bombardment of Earth B. C. Johnson & H. J. Melosh Nature 485, 75–77 (2012) Cite this article ...

NASA's Perseverance rover has added to its trove of curious finds, as the space agency published a photo of a rock on the surface of Mars that looks like a centuries-old helmet. The rock has a pointed ...

The team are now working to link the spherule-rich texture observed at St. Pauls Bay to the wider stratigraphy at Witch Hazel Hill, and initial observations have provided tantalizing indications ...

The millimeter-scale gray circles are all formerly molten droplets ejected into space when an asteroid struck the Earth about 2.56 billion years ago. These droplets, known as impact spherules ...

Spherule layers — such as the one shown in this 5-centimeter, 2.6-billion-year-old sample from Australia — are markers of ancient collisions.

Sir David, 95, recalled the “electric moment” when tests showed the chemical profile of a “spherule” matched that of the asteroid.

The total length of viral filaments within the spherules was measured, revealing an approximate length of 18,600 ± 2900 Å and 21,400 ± 1600 Å per spherule (Figure 2B), which is equivalent to ...