Before Monday’s solar eclipse happens, eagle eyed skygazers will have a once-in-a-lifetime opportunity to see a rare green comet, dubbed the ‘Mother of Dragons’, in the night’s sky. According to astronomers, Comet 12P/Pons–Brooks is viewable at night from the northern hemisphere in early April.
Larger than Mount Everest, it should appear as a green blob with a hazy tail as it makes its first visit to the inner solar system in 71 years. To see Comet 12P/Pons-Brooks, look westwards in the night’s sky and find the constellation of stars known as Aries the Ram, which forms a loose V-shape.
Over the next few weeks it will keep moving west towards Orion, the constellation that looks like the great mythical hunter. ‘The comet can now be found in the constellation of Aries which is visible in the early evening, over in the west,’ Gregory Brown, astronomer at the Royal Observatory Greenwich, told MailOnline.
‘It will only become visible after twilight and sets by around 10pm BST. ‘While it may be possible to see with the unaided eye, it is best to try and observe with a pair of binoculars or a small telescope.’ The public should look out for what looks like ‘an irregularly shaped dirty snowball’, or a faint star-like blob with a hazy tail and a green tint.
It looks green due to the presence of a molecule called dicarbon, which emits a greenish glow from sunlight. At the moment, it is getting progressively closer to the sun and the Earth as it’s pulled by the gravity of our star.
On April 21, it will come as close as 72.5 million miles (116.8 million km) to the sun, while a close approach with Earth of 144 million miles (232 million km) will happen on June 2. But by this time it will be too late to view in the northern hemisphere, according to Jessica Lee, astronomer at the Royal Observatory Greenwich.
‘From June onwards, after the comet has passed the sun, it will only be visible to observers in the southern hemisphere,’ she told MailOnline. ‘It will grow fainter and fainter again as it travels towards the outer solar system and won’t approach the Earth again until 2095.’
12P/Pons-Brooks is what is known as a cryovolcanic – or cold volcano – comet, which means it exhibits volcanic activity. But instead of spewing out molten rock and lava like a volcano on Earth, a cryovolcanic comet releases a mixture of gases and ice.
When a cryovolcanic comet gets closer to the sun – like 12P/Pons-Brooks is doing now – it heats up and builds pressure in the nucleus. The pressure continues to build until nitrogen and carbon monoxide explodes and flings out icy debris through large cracks in the nucleus’s shell.
These gaseous streams can form distinctive shapes when viewed through a telescope, such as devil horns, also described as a horseshoe or the Millennium Falcon from Star Wars.