Imagine yourself sitting on a rock on the dark side of Moon, gazing up at the Milky Way. There's no stray lights, no atmosphere to dull your view of the night sky. The stars are so brilliant, so big, you could reach out and touch them.

We can’t take you to the dark side of the Moon just yet, so find yourself a nice dark area of the garden. You can see some of the brightest stars in the sky during these cold August nights.
As our gaze turns to the north, the most prominent stars are Vega, Deneb and Altair.

Altair is the brightest star of the constellation Aquila. The names Altair and Aquila both mean "eagle"; the constellation looks like a giant bird with its wings spanning the Milky Way. The constellation Aquila is a skywatching rarity - a pattern of bright stars that really does resemble its namesake. Altair is a strange star. It rotates on its axis in just 6 and a half days (the Sun takes 25 days). As a result of this rapid spinning, the star probably has a very flattened shape, the equatorial diameter being nearly twice the polar diameter.

Of the three stars, Deneb is found lowest in the sky. It marks the "tail" of Cygnus, the swan. Deneb is one of the biggest and heaviest stars in the galaxy - and one of the most distant that's visible to the unaided eye. It's about 25 times as massive as the Sun, and about 200 times wider. It burns so hot and bright that it's easily visible across more than 2,000 light-years of space.

Vega is a white star, somewhat larger and brighter than our Sun, about 25 light-years away. Its white colour means that Vega also is hotter than our yellow Sun.
About 40 years ago, astronomers found that a broad disk of warm dust grains surrounds Vega. But the disk has big lumps and gaps. These may be caused by the gravity of planets orbiting the star, which sweep away the dust in some areas of the cloud, and cause it to clump together in others.

The clumps may be caused by a planet about as massive as Neptune, one of the giants of our own solar system. But there's evidence of smaller planets, too, orbiting much closer to the star.
About 14,000 years ago, Vega was the northern “pole star”. Today, the pole star is Polaris. But the star that marks the north celestial pole changes over time because Earth wobbles on its axis. The wobble, which resembles the wobble of a child's spinning top, is caused by the gravitational pull of the Sun and Moon. It takes about 26,000 years to complete one circle.

As our gaze moves overhead, we see the familiar constellation of Scorpius, the scorpion; another of the few constellations in the sky that really looks like what it represents.
Overhead at this time of the year, the centre of our Milky Way galaxy, is bright, crowded, and busy. It's filled with fast-moving stars, big clouds of gas, and turbulent magnetic fields; all surrounding a supermassive black hole that's at least two million times heavier than the Sun.

The black hole contributes to the chaos around it; both by pulling in stars and gas, and by spitting some of them back out again. It's encircled by a spinning disk of very hot gas that's spiralling into the black hole. This spinning gas produces huge amounts of X-rays. The gravity of the black hole is so powerful that anything that enters it is trapped - including light.
As darkness falls on the night of August 2nd, look high up the western sky. The first quarter Moon passes by a star with one of my very favourite star names - Zubenelgenubi.

The Arabic name "Zubenelgenubi" means the "the southern claw." Thousands of years ago, it and the star that stands above it and to the right; Zubeneschamali, the northern claw; were part of Scorpius, the scorpion. But later, they were stripped away and assigned to a new constellation: Libra, the balance scales.

If you have clear skies and good eyesight, you might notice that Zubenelgenubi consists of two stars that are quite close together. The stars are bound to each other by gravity, so they travel through the galaxy as a pair. They are 288 light years from Earth. The light arriving now, left when the first successful appendectomy was performed by English surgeon William Cookesley in the early 1730’s.
What you can't see, though, is that each of these stars is actually a pair on its own. So, the entire system consists of four stars. Three of them are bigger and hotter than the Sun, while the fourth is smaller and cooler. All four appear to be around 200 million years old.
Look to the south-east, and using this month’s starchart locate the flock of birds that make up many of the constellations in this part of the sky. Make sure you’re observing from a dark spot, as all of these constellations are faint. You’ll find Tucana, the toucan, Grus, the crane and Pavo, the peacock. Within the constellation of Tucana is located one of the finest examples of a globular star cluster in the sky.
Using binoculars, locate the object labelled 104 (also known as 47 Tucanae) on the star chart. In binoculars it resembles an out-of-focus star. You can just make it out with the naked eye from the city. It's actually a vast aggregation of some 1 million stars, all arranged in a spherical ball, about 15,000 light years away. The average distance between stars in this cluster, known as a globular cluster because of its shape, is 1 light year. This is about 4 times greater than the star density we are used to in our neighbourhood. Imagine a sky filled with thousands of stars all shining brighter than Sirius. What a sight that would be! If you’re looking at this through binoculars or a telescope, make sure to breathe. Holding your breath, and starving your body of oxygen reduces the sensitivity of your eyes to see faint objects.

Oxygen is one of the most important elements on Earth. It makes up about one-fifth of the mass of the atmosphere, nine-tenths of the mass of water, and two-thirds of the mass of the human body. It’s a by-product of plant life, and a necessity for animal life. And it combines with other elements to make everything from water to rocks.
All of the oxygen atoms on Earth, and throughout the universe, for that matter, were made by stars.

When a star is born, it’s made mainly of hydrogen, the simplest chemical element, which was forged in the Big Bang. For most of its life, the star fuses the hydrogen in its core to make helium. At the end of its life, a star as massive as the Sun or heavier fuses the helium to make heavier elements. A star like the Sun makes carbon and oxygen, while heavier stars make even more elements, all the way up to iron.

Over the 14-billion-year history of the universe, stars have made more oxygen than any other element, so it now accounts for about one percent of all the atoms in the universe.

When a star dies, it expels much of its gas into space. Stars like the Sun do so in a fairly gentle process, creating beautiful clouds that eventually dissipate. More massive stars do it more explosively, blasting out debris at a few percent of the speed of light. This mixture of elements can then be incorporated into new stars and planets, and at least in the case of our own Earth, into living organisms as well.
The Moon is at First Quarter on August 1st, Full on the 9th, at Last Quarter on the 16th, New on the 23rd, and at First Quarter again on August 31st.

Happy observing!