EYES ON THE NIGHT SKY: APRIL 2019
Welcome to our April edition of Eyes on the Night Sky, where we will select some night-time highlights for this month. As the clocks have gone forward, darkness will not descend until at least 9.30pm at the beginning of the month and around 11.30pm at the end. True darkness, where the Sun is more than 18 degrees below the horizon, is ideal for viewing distant galaxies, star clusters and nebulae.
If you haven’t yet seen the Zodiacal Light, the first six days of April is the last opportunity you will catch it. You will see it at least 1.5 hours after sunset in the West. You will also need a dark sky and dark adapted eyes to discern the beautiful, cone-like beam of light. The photograph above has been enhanced to show the structure but to the unaided eye it is at least 20% less bright.
A Stunning Conjunction
There are some planets to study this month – the two most notable ones are Mars and Jupiter. Throughout this month, Mars climbs higher into the western sky. On 8th April, from 9pm, look out for a lovely sight; the Red Planet will lie 8° almost directly above the waxing crescent Moon in the western sky. In addition to this, look for a fan-shaped conjunction of Mars, the Moon, the Seven Sisters Star Cluster at the 2 o’ clock position to the Moon and bright Aldebaran and a v-shaped asterism which forms part of the Constellation of Taurus at the 11 o’ clock position. A spectacle for the unaided and those wanting to photograph it.
If you want to study Jupiter it is visible in the morning sky as it rises at 2am at the beginning of the month and 12.30am at the end. This gas giant is a wonderful planet to study, with the dance of its many moons and the brief glimpses of cloud formation on its surface. For those wanting to study the Great Red Spot, here are the times you will be able to see it in the UK.
The New Moon falls on 5th April and the Full Moon is on 19th April.
Although at low declination, Saturn can still be studied. It rises at 3am at the beginning of the month and around 1am at the end. Through a small telescope, try to pick out detail in the rings which a currently open.
Sombrero Galaxy (M104 or NGC 4594)
April is a great month to study many galaxies, as the Constellation of Virgo can be seen in the South east to southern sky at around 10pm. Situated just below the right hand side of the ‘body’ or Virgo is the Sombrero Galaxy, which can be seen with binoculars in a dark sky. It was named, as such, because the shape of the galaxy resembles a sombrero hat. Look at the star Spica and raise your binoculars to meet your eyes. Scan slowly a short distance to the right until you see an oval smudge of light. Through small telescopes, it will appear to be brighter and you may be able to see a hint of the dark dust lane but in dark skies, through larger telescopes of 8 inches and above, the dust lane will become more apparent.
This spiral galaxy is 29 million light years away from us and is 50,000 light years in diameter. This galaxy is 4/5ths the solar mass of the Milky Way, which is around 1 trillion solar masses. The Sombero Galaxy contains around 2000 globular clusters and a massive black hole, which may be the most massive discovered in a galaxy so far. From our perspective, we are unable to see the spiral shape of the galaxy as it is edge on.
Constellation of the month: Virgo
The second largest constellation, Virgo is an impressive constellation with many wonders and myths. What we know about this constellation is that 20 of its stars have been discovered to have planets within its systems, the most so far in all the constellations. The image below can be enlarged by clicking it - but an even larger image (zoomable) can be viewed.
Virgo cluster of galaxies image taken with the Palomar Observatory 48-inch Schmidt telescope as part of the Digitized Sky Survey. Credit:NASA, ESA, and the Digitized Sky Survey Acknowledgment: Z. Levay (STScI) and D. De Martin (ESA/Hubble)
This constellation also contains a massive cluster of galaxies called the Virgo Cluster. It contains nearly 2000 galaxies and is in the heart of the Virgo Supercluster. The Local Group, which contains the Milky Way, is a member. The short video below will hopefully assist you in making sense of it!
In Greek mythology, the Virgo Constellation is associated with Dike, the goddess of justice and daughter of Zeus. She is located by the constellation of Libra which represents the scales of justice. Dike was born a mortal and lived among humans, ruling over them in the area of justice. She lived during the Golden Age of mankind, where peace of prosperity reigned in a never-ending spring and humans were perpetually young.
Zeus overthrew his father Kronos and the silver age commenced, bringing in the four seasons. Humans lost interest in the gods and Dike warned them not to abandon the traditions of their fathers and allow mankind to deteriorate.
In utter frustration, she left them and fled to the mountains, watching from afar. When she observed the Bronze and Iron age civilisations fighting against each other in tribal warfare, she gave up on earth and flew to the heavens.