Two bright beacons hold centre stage in our night sky during February. In the beautiful pastel hues of an Australian summer sunset.

Two bright beacons hold centre stage in our night sky during February. In the beautiful pastel hues of an Australian summer sunset, you’ll find the brilliant planet Venus shining like a celestial lighthouse low in the western sky. Over in the north-eastern sky, you’ll find another bright star. That is the planet Jupiter, the largest of all the planets.
Venus, the “evening star”, is our closest planetary neighbour. It’s coming closer to us in its smaller, faster orbit around the Sun. At the beginning of the month it will be 76 million kilometres from Earth.
As it does so, sunlight illuminates less of the hemisphere that faces our way. The combination of the closing distance and therefore larger size are such that Venus will continue to gain an even greater brilliance in coming weeks. A view in a telescope will show Venus to look like a crescent Moon only a few days old.
Venus’s phases were discovered by the famed Italian astronomer Galileo Galilei. He was the first to turn a telescope toward the heavens. Among other wonders, he saw that Venus went through a cycle of phases, just as the Moon does. His discovery confirmed that Venus orbits the Sun, placing our star at the centre of the solar system instead of Earth.
Turn your gaze further to the north, and you’ll be greeted by the colossus of the solar system, Jupiter. You can find it amongst the stars of Taurus, the Bull. Not as bright as Venus, the giant planet dominates that part of the sky. It’s reflecting sunlight from a whopping distance of 760 million kilometres.
We calculate distances across the solar system, and with authority proclaim that Jupiter is currently 760 million kilometres away. But do we appreciate that distance? To try and put it in some perspective, imagine that the Sun is represented by a soccer ball in the middle of an oval. Put the ball down and walk ten paces in a straight line. Stick a pin in the ground. The head of the pin stands for the planet Mercury. Take another 9 paces beyond Mercury and put down a peppercorn to represent Venus. Seven paces on, drop another peppercorn for Earth. Twenty five millimetres from Earth, another pinhead represents the Moon. Fourteen more paces to little Mars, then 95 paces to giant Jupiter, a ping-pong ball. Saturn is a marble, a further 112 paces. You’ve now reached the goal posts.
But, how far would you have to walk to reach the nearest star, Proxima Centauri? Pick up another soccer ball to represent it, and set off for a walk of 6720 kilometres to Hong Kong! Enjoy your walk!
Now, for the permanent stars in our sky. Orion is a big summer constellation that dominates the evening sky. It’s associated with a big Greek myth; one that spans several other constellations. Some of them surround the hunter, while another is on the opposite side of the sky, a separation designed to keep two mortal enemies apart.
Orion is high in the northern sky as night falls. The bright orange star Betelgeuse marks his shoulder, with brighter blue-white Rigel as his foot, and his three-star belt between them.
In mythology, Orion was one of the big celebrities of his day. He was strong, handsome, and a great hunter. Two of his hunting dogs follow him across the sky; Canis Major and Canis Minor. They’re pursuing Lepus, the rabbit, which bounds below Orion’s feet.
But Orion’s celebrity eventually went to his head, and it cost him his life.
There are different versions of his demise, but they end the same way. One says that Orion boasted that he could kill any animal on Earth. That didn’t sit well with the Earth goddess, who sent a giant scorpion after him; a scorpion that stung him to death. Another version of the story says he was pursuing the goddess Diana a little too vigorously. So her brother, Apollo, dispatched the scorpion to protect her virtue. Either way, Orion met his fate through the scorpion’s sting.
The gods placed both Orion and Scorpius in the stars, but halfway around the sky from each another. So, Orion dominates the summer sky, while his mortal enemy, the scorpion, rules the nights of winter.

Sirius, the brightest star in all the night sky lies almost overhead at the beginning of February. It’s the brightest star of the constellation Canis Major, the big dog, so it’s also known as the Dog Star.
Like all the stars that twinkle in the night, Sirius’s brightness is a combination of two factors: its true brightness and its distance.
In fact, Sirius really is a bright star, about 25 times brighter than the Sun. That’s because it’s about twice as massive as the Sun. It “burns” the nuclear fuel in its core in a hurry, so it produces lots of radiation. That energy pushes outward on the surrounding layers of gas, making Sirius bigger than the Sun. It also heats the gas to higher temperatures, so any given area on Sirius radiates more energy into space than the same-size area on the Sun. The combination of the size and surface temperature makes Sirius a real shiner.
The other reason Sirius shines so brightly in Earth’s night sky is its proximity, just 8.6 light-years away. That makes it the fifth-closest star system to our own. And thanks to the relative motions of Sirius and the Sun, Sirius is inching closer, at about 27,000 kms per hour, about as fast as the International Space Station orbits Earth. It’ll continue to close in for tens of thousands of years. But the distances between the stars are so huge that even at that speed, Sirius won’t get much brighter.
The Moon is at First Quarter on February 5th, Full on the 12th, at Last Quarter on the 21st, and New on February 28th.

Happy observing!