Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind, which carries charged particles mainly in the form of electrons and protons, and precipitates them into the upper atmosphere (thermosphere/exosphere), where their energy is lost.

This composite image uses successive pictures recorded during the eclipse from Athens, Greece to trace out a large part of the umbra's curved edge.

Titan is the largest moon of Saturn. It is the only moon known to have a dense atmosphere, and the only object in space, other than Earth, where clear evidence of stable bodies of surface liquid has been found.

Astronaut Neil Armstrong on the moon's surface

The aurora is caused by the interaction of solar wind - a stream of charged particles escaping the sun - and Earth's magnetic field and atmosphere.

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The great solar of eclipse of 2017, resulted in the moon's penumbral shadow yielding a partial eclipse visible from a large region covering most of North America.

A giant cluster of about 3000 stars called Westerlund 2. The cluster resides in a raucous stellar breeding ground known as Gum 29, located 20 000 light-years away in the constellation Carina - photo: NASA

In western culture, the name "Milky Way" is derived from its appearance as a dim un-resolved "milky" glowing band arching across the night sky. The term is derived from the Hellenistic Greek for "milky circle." In Greek mythology, the Milky Way was supposedly made from the forceful suckling of Heracles, as Hera acted as a wet nurse.

Arctic Islands Voyage

Sunspots tend to appear in cycles of 11 years and can sometimes erupt into powerful solar storms that shoot streams of charged particles into space, occasionally in the direction of Earth. Some solar storms can bombard Earth's magnetic field and disrupt power grids or knock out satellites in orbit!

Photo by Krista Trinder, showing the newly defined type of skyglow, created by the glowing of heated electrons entering the ionosphere.

Long wavelengths, such as infra-red or radio waves can make it through the Earth's atmosphere without significant obstacles. In fact, radio telescopes can observe even on cloudy days.

According to our best available estimates, stars having about 90 percent of the sun's mass are just now starting to die in the globulars. These stars are most probably around 15 billion years old, but they could conceivably be as young as 12 billion years or as old as 18 billion years.

Photography by Lincoln Harrison - There are two methods popular with star photographers – using one very long exposure (long enough to register some noticeable star movement; at least 30 minutes) OR taking many shorter exposures and stacking those images in a way that shows sequential movement.

Sunspots tend to appear in cycles of 11 years and can sometimes erupt into powerful solar storms that shoot streams of charged particles into space, occasionally in the direction of Earth. Some solar storms can bombard Earth's magnetic field and disrupt power grids or knock out satellites in orbit!

The moon, framed by ashes from the Mount Sinabung volcano, penumbral eclipse from Karo in North Sumatra province on August 8, 2017

Many features of the moon are named after famous individuals. Amongst others, several craters of the moon are named after Scottish scientists, including John Napier, and James Clerk Maxwell.

Many features of the moon are named after famous individuals. Amongst others, several craters of the moon are named after Scottish scientists, including John Napier, and James Clerk Maxwell.

Panorama created from photos taken on the fourth crewed Moon mission, Apollo 15, which landed in August of 1971

Astronaut Neil Armstrong on the moon's surface

Astronaut Neil Armstrong on the moon's surface

As a comet gets closer to the Sun, some of its frozen gases sublimate creating a coma – a bright envelope of atmosphere that surrounds a comet. These gases can reflect sunlight which is visible in the form of two tails. The ion tail – a collection of charged particles pushed away by the solar wind – will begin to glow with a blue tint.

The Dog Days of summer, generally reckoned to begin July 3rd and ending August 11th, coinciding with the rising of the Dog Star, Sirius, in the constellation Canis Major.

Astronomically, a "blue moon" is an additional full moon that appears in a subdivision of a year: either the third of four full moons in a season, or a second full moon in a month of the common calendar, depending on the astronomical or the current common definition.

The term black moon refers to an additional new moon that appears in a month or in a season. It may also refer to the absence of a full moon or of a new moon in a month.

Massive solar flares are sometimes accompanied by coronal mass ejections which can trigger geomagnetic storms that have been known to disable satellites and knock out terrestrial electric power grids for extended periods of time.

Harvest Moons often appear larger and more colourful than other moons of the year, aided by the tilt of the earth and reflections from the atmosphere.

The aurora is caused by the interaction of solar wind - a stream of charged particles escaping the sun - and Earth's magnetic field and atmosphere.

Astrobiology is a branch of biology concerned with the origins, early evolution, distribution, and future of life in the universe. Astrobiology considers the question of whether extraterrestrial life exists, and how humans can detect it if it does.

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“Indian summer” is a phrase most North Americans use to describe an unseasonably warm and sunny patch of weather during autumn.

As seen from Earth, Mercury appears to cross the disk of the sun — an event known as a transit — only about 13 times per century.

The nebula is easily seen within the belt of the constellation of Orion the hunter. The brilliant reddish color of the nebula. That comes from ionized hydrogen gas, which emits a characteristic red emission line when electrons fall back down in the orbitals of hydrogen atoms.

The first attempt by the United States to land on Mars was originally planned for July 4, 1976, the United States Bicentennial, but imaging of the primary landing site showed it was too rough for a safe landing. The landing was delayed until a safer site was found, and took place instead on July 20, the seventh anniversary of the Apollo 11 Moon landing.

tracks from Curiosity Rover

Recent experiments have detected multiple instances of gravitational waves, predicted more than a century ago by Einstein’s theory of general relativity.

The Cold Moon is also known as the Long Night's Moon and the Moon before Yule.

In astrophysics and physical cosmology, Olbers' paradox, also known as the "dark night sky paradox," is the argument that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe.

"Earthrise," a word coined from the name of a photograph of the Earth taken by astronaut William Anders in 1968, during the Apollo 8 mission.