“Mars has only half the diameter of the Earth, but because it has no oceans, its surface area is actually greater than the Earth’s land surface. “
“The Vernal Equinox, where the Sun crosses the equator on its way north in spring, moves steadily along the Ecliptic (the plane of the Earth’s orbit, projected on to the sky) from year to year “
” “Our research shows that the sulphuric acid clouds in Venus have too little water for active life to exist, based on what we know of life on Earth.” Dr John E. Hallsworth
Duncan Lunan who writes The Orkney News astronomy column and beginner’s guides is also the man behind the building of the Sighthill Stone Circle.
Like last month, it will never be completely dark during July, as the Sun never gets far below the horizon. It’s a good time to see noctilucent (night-glowing) clouds in the north, lit by sunlight at high altitudes, first reported in the 19th century and still not fully explained.
“If the Earth had no atmosphere, life would be much easier for astronomers – as long as they didn’t need to breathe. “
Although it can be seen in daylight if you know exactly where to look, Venus is the morning and evening star, generally seen in twilight and hardly ever against a truly black sky.
Find out more about the planet Mercury from our guide by Duncan Lunan
This spectacular image from the NASA/ESA Hubble Space Telescope shows the trailing arms of NGC 2276, a spiral galaxy 120 million light-years away in the constellation of Cepheus
“The Moon will be New on June 10th, at its furthest from the Earth, and there will be an annular solar eclipse”