April Sky Notes
Written by John StapletonImage Credit: Popular Science
All Eyes on the “Devil Comet”
In earlier times, comets were seen as portents of disaster and this has continued with the tendency to attach names based on superstition to comets and to view comets as potential threats, especially in the media. The comet depicted in the Bayeux Tapestry, which has proved to be an early record of Halley’s Comet, was said to foretell the Norman invasion and the death of Harold. The same comet was seen to return in 1911, when scientists at the time predicted that the Earth would actually pass through the tail of the comet and certain noxious gases may be spread throughout the Earth’s atmosphere. This caused many people to seek shelter underground in mines and caves.
Comet 12P/ Pons-Brooks has been a binocular object through March. The comet has undergone an outburst that has made it considerably brighter than originally predicted and the hope is that this visitor from the outer Solar System will reach naked-eye magnitudes in early April. The outburst also changed the visual appearance of the comet, as seen through telescopes, from a fuzzy blob to a horseshoe shaped object with two streamers, or “horns” from the ends. This has earnt the comet the nickname “The Devil Comet” although other observers have likened its appearance to that of the Millennium Falcon from Star Wars!
During the first half of April the comet can be seen low in the North-Western sky just after sunset. With the change to British Summer Time having taken place on March 31st there is only a brief window of opportunity to spot the comet before it is lost in the brightening evening sky. Fortunately the comet will be close to, and below, the bright planet, Jupiter on April 13th, and 14th so the giant planet will provide a useful marker to help find the comet. By this time, Pons-Brooks should be bright enough to be seen with the naked-eye, however, the brightening twilight may make this difficult and the use of binoculars is recommended.
Sky Notes
Please note all times given in this article are in GMT so remember to add an hour to get the time in BST which started on Sunday 31st March.
See April Sky Schedule
Sun: On the 1st April, the Sun rises at 06:47 and remains in the sky for 13 hours. This means that it does not get truly, astronomically, dark until about q quarter to ten. By the end of the month, the sun rises at 05:48 and remains in the sky for 14 ½ hours so that astronomical darkness does not fall until around 11 o’clock. On April 8th there is a total solar eclipse visible in North America. Residents of the extreme West of Britain (West Wales, West Cornwall and the Western Isles of Scotland) may see a small partial eclipse just minutes before the Sun sets, if they have a low enough horizon.
Mercury: Mercury may be seen at the beginning of the month but it reaches inferior conjunction (between the Earth and the Sun) on 11th and so is not visible.
Venus: Venus also lies close to the Sun and is not visible this month.
Mars: Mars is poorly placed in the morning sky and will become more easily visible towards the end of the month.
Jupiter: The largest planet is a bright early evening object in the Western sky as the sun sets. It lies in the constellation of Aries and will be a useful marker helping to locate Comet Pons-Brooks. The change to British Summer Time, however, means that by the middle of the month, both the comet and Jupiter will be lost in the increasing daylight.
Saturn: The ringed planet rises just before the Sun but remains too close to our star to be easily seen this month.
Uranus and Neptune: Uranus is still visible in the constellation of Aries but, like Jupiter, is lost to the evening glare by the middle of the month. Neptune is not visible this month.
Meteor Shower: April is our first chance of the year to see shooting stars, or more formally meteors. The Lyrid meteor shower falls in April. It appears to come from a point in the sky lying in the direction of the background constellation of Lyra and so is known as the April Lyrids. Look out for these meteors between April 16th – 25th. The peak time falls on the night of 22nd -23rd. Meteors are the remnants left in the path of comets as they orbit the Sun. We see them when the Earth passes through a cloud of these remnants. The April Lyrids are the remnants of Comet Thatcher. This year the Moon is nearing Full and so its light will drown out all but the brightest meteors. The Lyrid meteors are relatively slow-moving and can include some bright shooting stars.
Comet: Comet 12P/Pons-Brooks will be visible at the beginning of the month.
ISS: The International Space Station will be visible on the 7th April for an early evening pass with a duration of 5 minutes starting at 19:00, Coming in from North-North-West and leaving North-East at 19:05. Then on the 12th April an early morning pass with a duration of 6 minutes starting at 04:57, Coming in from the South-South-West and leaving South-East at 05:03.
Moon: The Last Quarter Moon occurs on April 2nd with New Moon following on 8th. The First Quarter Moon is then on 16th with Full Moon occurring on April 23rd. The next Last Quarter then falls on May 1st .