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New by me for Live Science:

For many ancient cultures, eclipses of the sun and moon were something special — and something to be feared.

Source: Afraid of the Dark? Why Eclipses Frightened Ancient Civilizations

Also: Kepler’s fictional explanation for human fear of eclipses in Somnium is characteristically exotic:

From: https://somniumproject.wordpress.com/x/

 

Solar and lunar eclipses have sometimes played quite a remarkable role in human history. From foretelling evil omens to inspiring early works of science fiction, here are 11 of the most curious stories about eclipses.

Source: Christopher Columbus to Thailand’s Kings: 11 Curious Eclipse Stories

Historians discuss astronomer Johannes Kepler in this BBC4 radio broadcast.

Source: BBC Radio 4 – In Our Time, Johannes Kepler

The Science Geek

As most of you will already know, and much to our disappointment, the Schiaparelli probe failed to land successfully on Mars last Wednesday. The plan was that when it entered the Martian atmosphere, the spacecraft would immediately begin to slow down to 1700 km/h as a result of the friction caused by the atmosphere hitting its heat-shield.  When it reached this speed, and was 11 km above the Martian surface, a parachute would open for two minutes to slow it down to 240 km/h. The parachute would then be jettisoned to get it out of the way, allowing thrusters to fire like the brakes on an aeroplane.  The spacecraft would then touch down on the planet’s surface at a gentle 10 km/h.

schiaparelli_landing

Image from ESA

Unfortunately, what appears to have happened is that the parachute only opened for a few seconds and so failed to slow the spacecraft down. The spacecraft will have crashed into the surface at thousands of…

View original post 1,003 more words

The Science Geek

The June solstice will fall on June 20 or June 21 this year, depending on where you are in the world.  It is the longest day in the northern hemisphere and the day when the Sun is at its highest in the midday sky (see note). The origin of the word solstice is from the Latin words sol, which means Sun, and sistere, to stand still, because around the time of the solstice the Sun stops getting higher, appears to stand still at the same height for a few days, and then gets lower in the midday sky.

The graph below show the maximum height, or elevation, of the Sun, measured in degrees above the horizon, during the month of June. The graph is for a place 50 degrees in latitude North, roughly the same latitude as the southern tip of the British Isles.  It shows how the elevation of the Sun changes around the solstice.

Sun height June

The…

View original post 824 more words

The Seasons of the Moon [The duration of summer and winter on the moon, and the climate zones of the lunar globe] Est autem circulus aliquis inter polos intcrmedius, viccm gerens nostri aequatoris …

Read more at: Page XIV

 

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