April Lyrids Meteor Shower
April 2008 :
Note: This article may contain outdated information
This article was published in the April 2008 issue of The Skyscraper and likely contains some information that was pertinent only for that month. It is being provided here for historical reference only.
The eclipsed Moon was still quite bright. It showed subtle hues of red and orange, but did not vanish from the sky. The Moon was a beautiful sight to see nestled within the stars of Leo, with bright Regulus shining above and even brighter Saturn to the lower left.
More than 200 folks braved the chilly weather and visited Ladd Observatory in Providence to catch a glimpse of this wonderful lunar eclipse through a variety of telescopes and binoculars.
There is one event I would like you to view during early April, and that's the passage of the Moon through the Pleiades star cluster. This pattern of stars is also known as the Seven Sisters or Subaru. Check out the emblem on the cars of the same name!
On April 8 observers here in the northeast can watch the three- day old crescent Moon pass in front of a few of the stars in the Pleiades cluster before moonset. You'll need a good west north-west horizon for the best viewing advantage.
After sunset look westward and locate the Moon. Once it gets dark you'll see the star cluster up and to the left of the Moon. Beginning around 9:45 pm EDT the earthshine (reflected sunlight from the Earth projected onto the lunar surface) edge of the Moon (not the sunlit crescent side) begins to pass in front of some of the cluster's stars. A pair of binoculars or a small telescope often provides the best view during this astronomical event called a stellar occultation.
A note of interest: whatever phase the Moon is in, if you were on the Moon's surface looking back at the Earth, the Earth would be in the opposite phase. In the above scenario, from the Moon the Earth would be three days past full. Therefore, the earthshine on the lunar surface not illuminated by the Sun is the reflected light from a very large and bright Earth in the lunar sky.
If you are a meteor observer I don't need to tell you that either the weather or Moon has conspired to bring meteor observing to a standstill during the last few months. And besides those factors, there were no major meteor streams visible to us during February and March.
While I wish I could say that April will reverse these poor observing trends, bright moonlight will certainly spoil the view of the Lyrids meteor shower, which peaks this year on the night of April 21 to the morning of the 22nd.
Unfortunately the bright gibbous Moon, only two days past full, will drown out all but the brightest of the April Lyrid meteors. This shower peaks around midnight, so I would suggest starting your observing program an hour before. Face the eastern sky and try to use a building to shield your eyes from direct moonlight. The constellation Lyra, from where the meteors will appear to radiate, will be well up in the eastern sky.
The swift and bright Lyrid meteors disintegrate after hitting our atmosphere at a moderate speed of 29.8 miles per second. They often produce luminous trains of dust that can be observed for several seconds. Some recent observations indicate increased activity during the last few years.
Because moonlight will interfere by brightening the sky, an observer can expect to see perhaps 10 or less meteors per hour (below the normal peak rate of 15 to 20 per hour). Since the Lyrids are a narrow stream of particles, the nights before and after the peak will display even less meteors, given the ever present moonlight.
So despite less than ideal observing conditions, I still encourage you to make an effort to catch a glimpse of a few shooting stars during the April Lyrids display. It will be good to get out under the stars once again after the poor winter weather we've experienced. We can also do without Mother Nature's April rain showers thank you very much!
Seagrave Observatory on Peeptoad Road in North Scituate is open to the public every Saturday night, weather permitting of course. Check the web site at http://www.theskyscrapers.org for times and any closure notice.
You can also visit Ladd Observatory (http://www.physics.brown.edu/physics/commonpages/ladd/) located on Hope Street on Providence's East Side on any clear Tuesday night (8-10pm).
Keep your eyes to the skies.
