astronomy club of asheville august 2016 sky events

Astronomy Club of Asheville

August 2016 Sky Events

The Planets this Month - page 2

See 5 Planets Simultaneously - page 3

Very Close Conjunction or Jupiter & Venus - page 4

Planet Highlights - page 8

Moon Phases - page 11

Sirius and the Dog Days of Summer - page 12

August 11/12 – Perseid Meteor Shower- page 13

www.AstroAsheville.org

http://www.astroasheville.org/

August 2016 provides an opportunity to see all 5 naked-eye planets in the early evening skies. Jupiter, Mercury and Venus will dominate the west while Mars and Saturn will reign in the south-southwest.

Although Mercury will be above the horizon at sunset all month, it is best viewed during the first 2 weeks of August when it is highest for the month –only 13º above the horizon at sunset and appearing lower as the month progresses. Binoculars will help in locating faint Mercury in the twilight.

Mercury reaches greatest elongation east of the Sun on August 16th, some 27º from the Sun but less than 13º above the western horizon due to the low angle of the ecliptic at dusk during the northern hemisphere summer.

Bright Jupiter and even brighter Venus will appear to be on a collision course all month with a very close conjunction occurring just after sunset on August 27th. That night the 2 planets will be separated by less than 1/10th of a degree! Here’s a great opportunity to put both of them in the same telescope eyepiece field-of-view. Use low power, as the 2 planets will be very near the western horizon (less than 8º above). Or, perhaps try observing them just before sunset when they are higher up.


August 2016 Sky Events – the Planets

All three planets, Jupiter, Mercury &

Venus, easily outshine the bright star

Regulus in the constellation Leo.



Locate all 5 Naked-Eye Planets Simultaneously

You may see all 5 naked-eye planets at the same time in the early evening during the first 2 weeks of August.This is the scene for the nights of August 4th & 5th, about 8:49 p.m. EDT.

Both the planets Saturn

and Mars, located on the

border of the constellation

Scorpius, outshine the

bright red giant star

Antares.

Looking high in the S-SW Looking low to the Western horizon

Leo

Scorpius

Image courtesy of

Sky & Telescope



A Very Close Conjunction of Jupiter & Venus

On the evening of August 27, 2016 the bright planets, Jupiter and Venus, will appear closest during their “approaching encounter” this month. On this evening, Jupiter and Venus will be separated by less than 1/10th

of a degree!

Although the 2 bright planets appear close, in reality (3 dimensions), Jupiter is some 450 million miles behind Venus!Locating faint Mercury (about 5º below & left of Jupiter) will be challenging, as it is even lower toward the horizon. Using binoculars should help.

Looking very low to the Western horizon

Saturday evening,

August 27, 8:33 p.m.

EDT (about 30 minutes

after sunset).________________________________

Jupiter (lower of the two)

and Venus are only 5½º

above the horizon at this

time.

Venus

Jupiter

Mercury

Mars and Saturn, well past their spring oppositions, are fading. They both remain in great viewing position this month – high in the sky at sunset. But view them early in the night before they descend too low into the W-SW horizon.

On the nights of August 20-25, watch Mars as it passes (from right to left) between the planet Saturn and the bright red giant star Antares.

Saturn’s rings are currently tilted a wide 26˚ toward us (near their maximum angle of 27˚); so the rings will look spectacular in the telescope eyepiece. You will be looking at Saturn’s rings from above on their northern face; not until the year 2025 will you be able to catch a glimpse of the rings from the planet’s southern face!

Neptune rises at 10:00 p.m. on August 1st and by 8:00 p.m. at month-end. It can be found this month in the constellation Aquarius.

Uranus rises in the late night hours all month. It can be found this month in the constellation Pisces.

You will need binoculars or a telescope to locate and observe the small distant disks of Uranus and Neptune.





Conjunction of the Moon with Mars & Saturn

On the evenings of August 11 - 12, the waxing gibbous Moon appears to glide past the planets Mars and Saturn.

The two planets easily outshine the red giant star Antares in the constellation Scorpius.

The Perseid meteor shower will also be at its best on these dates in the pre-dawn hours.

Image courtesy of Sky & Telescope



Linear Conjunction of Saturn, Mars & Antares

On the evening of August 23rd, the planets Saturn and Mars form a nice linear conjunction with the bright red giant star Antares.

The name “Antares” comes from the ancient Greek meaning “rival of Mars” (it rivals Mars in orange brightness).So, on this night, Mars is less than 2º from its orange stellar rival.

Although these 3 celestial objects appear close in our 2-dimensional view, Antares is some 604 light years behind the planets!

Image courtesy of

Sky & Telescope


August 2016 Planet Highlights

Planet Avg. Distance from Earth

Constella-tion(s)

Avg. Diameter in arc seconds

Avg. Mag-nitude

Comments

Page 1 of 3

Mercury 0.91

AUs

Leo & Virgo 7.7 0.5 Reaches greatest

elongation east on

August 16th

Venus 1.6

AUs

Leo & Virgo 10.5 -3.8 Forms nice

conjunction

with Jupiter

Mars 0.8

AUs

Libra, Scorpius & Ophiuchus

11.7 -0.5 Continues to be

in great viewing

position




Constella-tion(s)


Avg. Mag-

nitude

Comments

Page 2 of 3

Jupiter 6.3 AUs Leo & Virgo 31.5 -1.7 Forms nice

conjunction with

Venus

Saturn 9.7 AUs Ophiuchus 17.1 0.4 Continues to be

in great viewing

position

Uranus 19 AUs Pisces 3.6 5.8 Best viewed

after midnight

this month




Constella-tion(s)


Avg. Mag-

nitude

Comments

Page 3 of 3

Neptune 29 AUs Aquarius 2.4 7.8 Find it in the

late night sky

this month


The Moon – August 2016

Unless otherwise indicated, all times are EDT

** The “Grain Moon”

New Moon 2nd 4:45 p.m.

First Quarter 10th 2:21 p.m.

Full Moon** 18th 5:27 a.m.

Last Quarter 24th 11:41 p.m.


August 2016 Highlight:Sirius and the “Dog Days” of Summer

The ancient Romans and other cultures were aware that the brightest star in the nighttime skies, Sirius (nicknamed the Dog Star because it is located in the constellation Canis Major – the Greater Dog), rose in conjunction with the Sun during the period from July 3 to about August 11 each year.

They felt that the combination of the Sun and Sirius, rising and crossing the daytime skies together, was responsible for the extreme heat at the height of summer!

Some say that summer's "dog days" signify hot sultry days not fit for a dog.

On August 11th and the next few mornings, look low in the east-southeast about 20 minutes before sunrise for the helical rising (first dawn visibility) of Sirius as it emerges from the Sun’s glare.


August 2016 Highlight:Perseid Meteor Shower

On the night of August 11/12 the predictably great performing, annual Perseid meteor shower “peaks”.

Because the waxing gibbous Moon sets about 1:40 a.m. on Friday, August 12th, this year’s shower should be, with the help of some clear skies, a very dark and wonderful event during the prime meteor observing hours from 2:00 a.m. to dawn.

Earth orbits through the debris trail of Comet 109P/Swift-Tuttle in August (the source of the meteors), and the “shooting stars” appear to radiate from the direction of the constellation Perseus -- hence its name the "Perseid" meteor shower.

Several meteor shower experts are predicting this year’s (2016) Perseid meteor shower to reach a rate count as high as 150 meteors per hour!


August 2016 Highlight:

Perseid Meteor Shower

If you hope to see these meteors at their best, seek out a very dark site with clear views to all directions.

Viewing late at night is best; dress warmly and wear a hat; and recline in a lawn chair or on the ground with a blanket.

Look straight overhead or angled toward the radiant in the northeast.

Don’t let clouds on the night of August 11th/12th end your chances to see these meteors.

This meteor shower goes strong for several nights before and after August 11th/12th. So go out and observe them on any clear, dark night in that time frame!


August 2016 Highlight

Perseid Meteor Shower Peakson August 11/12 – Thursday night & Friday morning (pre-dawn)

The meteors appear to radiate from the direction of the constellationPerseus --hence the name "Perseid" meteor shower. They are best observed pre-dawn this year.

astronomy club of asheville august 2016 sky events

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