Did you know you can check out telescopes at the Library?

Orion StarBlast 4.5" TelescopeThanks to a generous donation from the Louisville Astronomical Society, LFPL is excited to offer telescopes for check out at the Southwest Regional Library. The lending period is for one week and is limited to Louisville Free Public Library cardholders in good standing, 18 years or older. Signing a Telescope User Agreement at the time of checkout is required. Go to the Library Catalog to reserve one today.

For more information on the telescope lending program, visit the Southwest Regional Library or call (502) 933-0029.

May in the Sky
By Frank Nelson, Sidewalk Astronomy Coordinator for the Louisville Astronomical Society

We have hit the middle of spring, when the temperatures are warming up, the sun sets around 9PM, and it gets dark early enough that we can do some stargazing in the middle of the week and still go to bed at a reasonable hour!  With the start of May, we are now into Galaxy season.  This is the prime time of year to see an island universe, or several all at once.  Get to the darkest sky you can find, like Bernheim Forest, the Parklands, or any of the Louisville Astronomical Society events at our dark sky site and Tom Sawyer Park.  Check our Facebook and website for dates and times.  The darker your sky, the better the views.

We will start with where to look.  As the sun sets in the west, look in the opposite direction, towards the Southeast.  Due east is a bright red star called Arcturus.  Lower on the horizon is a white/blue star named Spica.  And high in the sky due south is the bright white star Regulus.  These three stars will be the first three that you see as the sky gets dark.  This triangle is where we are aiming our telescopes and binoculars.  In the center of this larger triangle is a smaller triangle of not-as-bright stars.  These are Porima, a double star, and Vindemiatrix in Virgo, close to Spica along with the brighter Denebola in the tail of Leo.  Inside this triangle of stars you will find the Virgo Super Cluster.  Finding the Virgo galaxies, as they are sometimes called, is not that hard.  Start at either Denebola or Vindemiatrix and slowly move toward the other star.  Inside this invisible line in the sky are some fifty to sixty galaxies visible in an amateur telescope.  From the city and its light pollution some 20-25 of these objects are viewable in a 10” telescope.  Do you see a “star” that does not seem to come to a focus? Congrats! You just found a galaxy some fifty million light years away!  The star charts below will help you identify what fuzzy patch of light is which galaxy.  Write down what you see, then compare your observation with the charts and image below.  I am also including a link to the free program Stellarium, a planetarium program.  Enter in your city under locations, then zoom in to see the red ovals for all the galaxies in this area.  All told, there are THOUSANDS of island universes in this patch of sky, most of which require a camera and long exposures to find. 

In the Virgo cluster, as a beginner, don’t worry too much about which object you are observing.  Instead, spend some time and learn to tell the difference between a spiral and an elliptical galaxy.  Is there a core of light surrounded by a fainter halo? Is the circle distinct all the way to the edge? If the moon is out, do you see more or fewer points of light? This is a great part of the sky to really hone your ability to observe a faint patch of light.  Here is one last trick to use for this part of the sky: use as big of a field of view at a lower magnification you can.  If you have a 40mm eyepiece, use that to start, then move to a 30-34mm to increase magnification.  When you can see a bigger part of the sky it is easier to star hop.  Once you see a fuzzy patch of light switch to a higher magnification (a lower number on the eyepiece).  As you increase magnification the background sky will darken a bit making the galaxies a little easier to see.  When I drift through this area of sky I rarely use more than 100x magnification.  Take your time and enjoy knowing that every smudge is a whole island universe just like our Milky Way.

And finally, for those of you up early at sunrise, we have planets to look at.  Venus is a very bright “star” low on the horizon at sunset, soon to be lost in the glare of the sun.  As the sun comes up in the east, Jupiter is a bright point of light in the South/Southwest.  In a simple pair of 50mm binoculars, the four large moons can be seen in a straight line; watch night by night as these points move relative to the planet.  Saturn is closer to due south at sunset this month.  With a 3” telescope or larger, the rings are very visible.  In 50mm binoculars I can make out that the planet is not round, more oval in shape.  At the end of the month, the moon will get very close to Jupiter, then very close to Saturn.


May star map

Last Updated: 05/06/2019