New theoretical modelling of the ancient history of the Earth and the Moon suggests that the giant collision that spawned our natural satellite may have left Earth spinning very fast, and with its spin axis highly tilted. The simulations give new insight into the question of whether planets with big moons are more likely to have moderate climates and life.
The Moon’s Orientale basin is an archetype of “multi-ring” basins found throughout the solar system. New research has enabled scientists to reconstruct Orientale’s formation using data from NASA’s GRAIL mission. It is now thought that the 580-mile-wide feature was created 3.8 billion years ago by an impacting object some 40 miles across travelling at about 9 miles per second.
UK observers with a clear sky an hour before sunrise on Friday 28 October should look very low in the east-southeast to see the slim crescent of the 27-day-old Moon less than four lunar diameters away from largest planet Jupiter. The Moon and Jupiter are also joined by third-magnitude double star gamma (γ) Virginis, commonly known as Porrima.
Mercury is currently putting on a fine show in the east before dawn. Find a UK location with an unobstructed view due east an hour before sunrise to see the innermost planet some 6 degrees above the horizon from about 25 September—5 October. The very old crescent Moon lies just 2 degrees from Mercury at dawn on Thursday, 29 September.
Observers up for an extreme observing challenge may care to make an attempt at viewing the almost full Moon pass in front of planet Neptune soon after 8pm BST on Thursday, 15 September. The planet’s disappearance occurs at a low altitude in twilight for the British Isles, but can also be seen from a large swathe of Europe and western Russia.
A hundred days have passed since Mars was closest to Earth this year, but the Red Planet can still be seen in the early evening sky close to the jewel of the solar system, Saturn. If you wish to identify this pair of planets, then a convenient celestial marker in the form of the waxing crescent Moon passes by on the evenings of 8—9 September in the UK and Western Europe.
For the first time, astroarchaeologists have statistically proven that the earliest standing stone monuments of Britain — the great circles — were constructed specifically in line with the movements of the Sun and Moon, 5000 years ago. University of Adelaide researchers used innovative 2-D and 3-D technology to test the patterns of alignment in the standing stones.
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