This Month’s Sky – May 2015

What’s Up in the Sky
AAA Observers’ May Guide
By Tony Faddoul



May’s Evening Planets:

Mars is visible until about 8 PM in Taurus the Bull. Venus can be found in Gemini the Twins until 11 PM. Bright Jupiter will be in Cancer the Crab until 2 AM, setting earlier every morning until midnight by the end of the month. Find Saturn between Scorpius the Scorpion and Libra the Scales at 9 PM, and then earlier every evening; it will be up all night. Mercury is in Taurus the Bull during the first half of May for about two hours after sunset.


May’s Evening Stars: Spot Spica in Virgo the Virgin, Arcturus in Boötes the Herdsman, Vega in Lyra the Harp, and Castor and Pollux in Gemini the Twins. Also find the stars of constellations Cassiopeia, Cepheus, Draco, Virgo, Hercules, Ophiuchus, Leo, Cancer, Corona Borealis, and the two Dippers during the month.


May’s Morning Planets: Saturn is up between Scorpi-us the Scorpion and Libra the Scales until sunrise. Neptune will be in Aquarius the Water Bearer as of 4 AM, rising earli-er every morning by 2 AM at the end of May. Uranus rises in Pisces the Fish about an hour after Neptune. Dwarf planet Pluto will be in Sagittarius the Archer by 1 AM, rising earlier every night through the month



May’s Morning Stars: Spot the Summer Triangle of Vega in Lyra the Harp, Deneb in Cygnus the Swan, and Altair in Aquila the Eagle as of midnight and rising earlier every night. Look for reddish Antares in Scorpius the Scorpion,Arcturus in Bootes the Herdsman, along with the stars of constellations Lyra, Hercules, Libra, Corona Borealis, Scorpius, Sagittarius, Capricornus, Ophiuchus, Cassiopeia, Cepheus, Draco, and the two Dippers.


May Skylights

May 3   Full Moon at 11:40 PM

May 6   Eta Aquarid meteor shower peaks (dawn)

May 11 Last Quarter Moon at 6:35 PM

May 14 Moon at perigee (227,435 miles from Earth)

May 18 New Moon at 12:15 AM

May 19 Mercury is 6° north of the moon (morning)

May 22 Saturn is at opposition, brightest in 2015 shining at 0.0 magnitude

May 24 Jupiter is 5° north of the moon (morning)

May 25 First Quarter Moon at 1:15 PM

May 26 Moon at apogee (251,185 miles from Earth)



Times given in EDT.



Eta Aquarids Meteor Shower Peaks May 5-6

The Eta Aquarid meteor shower peaks this month, and the best viewing opportunity will be in the early morning hours of May 6, from around 2:00 AM until dawn. Its shooting stars will be more frequent at peak, but many can still be seen in the few days before and after.


Who can see the shooting stars?

This meteor shower favors the skies of the southern hemi-sphere. Those who live further south will see more meteors.

The southern hemisphere has the chance to see over 20 meteors per hour at peak under dark skies. However, a waning gibbous Moon on May 6 will reduce the visibility of many shooting stars. The southern U.S., most of Europe, and Central Asia will see about 10 per hour; the northern U.S., Cana-da, North Europe, and North Asia will see about 5 per hour.


What causes the Eta Aquarids?

Meteor showers are created when the Earth passes through the trail of a comet. Comet Halley is responsible for the Eta Aquarids display. As debris from the comet enters Earth’s atmosphere at high speed, the meteors burn up, creating a spectacle of shooting stars.

Halley orbits the sun every 76 years and it will be back in 2061. The Earth passes through Halley’s orbit in October too creating the Orionid meteor shower.


What is a Radiant?

In a meteor shower, the shooting stars appear to strike everywhere in the sky, but their paths trace back to one region in the sky. The spot where they originate is called the radiant.

Meteor showers are named for the constellation that coincides with their radiant. Hence, Eta Aquarids originate from the star Eta in the constellation Aquarius.


How to view the meteor shower?

Looking east to southeast, the meteors will seem to originate from the Y-shaped Water Jar in the constellation Aquarius. Find a dark spot, far away as possible from light pollution, and hope for clear skies. There is no need for any equipment to view the meteor shower, and you don’t need to know the constellations. Just look up, and enjoy!