Tag Archives: #astronomy

Galileo’s Icy Moon

Four hundred years ago Galileo made a discovery that fundamentally shaped our understanding of the universe and our place in it. Using his powerful telescope he observed that the planet Jupiter had moons, which he initially thought to be planets.

In March 1610, Galileo published his discoveries of Jupiter’s satellites and other celestial observations in Siderius Nuncius (The Starry Messenger). The scientific proof supported the Copernican heliocentric theory that the Sun is at the centre of the Universe, not the Earth.

NASA’s recently published photos, taken by the Juno Jupiter probe in December 2019, have provided us exciting new insights into the largest moon in the solar system.

According to Alessandro Mura, a Juno co-investigator at the National Institute for Astrophysics in Rome, the mapping of the north polar regions of the icy satellite Ganymede in infrared light has revealed a “phenomenon that we have been able to learn about for the first time with Juno because we are able to see the north pole in its entirety. The data show the ice at and surrounding Ganymede’s north pole has been modified by the precipitation of plasma.”

Image of Ganymede’s Trailing Hemisphere by the NASA Jet Propulsion Laboratory

Galileo the Astrologist

Did you know that Galileo read people’s horoscopes as a side business?

In Europe during the late Renaissance Astrology played a very important role for many people and was highly regarded as a “science” alongside Astronomy and Mathematics.

Military generals and noblemen would choose a particular date for their wedding or plan an important battle on a specific ‘lucky day’ based on their horoscope readings.

This is where the term if the stars align, meaning if everything goes really well, comes from.