january 2016-aca-sky

Astronomy Club of Asheville

January 2016 Sky Events

The Planets this Month - page 2

Planet Highlights - page 7

All 5 Naked-Eye Planets in the Dawn Sky - page 10

Moon Phases - page 11

Earth Reaches Perihelion on Jan. 4 - page 12

Quadrantid Meteor Shower Peaks - page 13

Comet Catalina in the Early Morning Sky - page 14

Lunar Occultation of the Star Aldebaran - page 18

www.AstroAsheville.org

http://www.astroasheville.org/

The only naked-eye planet visible in the early evening sky this month is Mercury, and its twilight appearance will last for only the first week of the January.

Find Mercury very low in the SW at dusk; use binoculars to assist you in spotting it.

Mercury reaches inferior conjunction (passing between the Earth and the Sun) on January 14th.

At its next inferior conjunction on May 9th, Mercurywill pass directly across the Sun’s disk for its first “transit” in 10 years. With clear skies, this 7½ hour event will be visible in its entirety from Asheville.


January 2016 Sky Events – the Planets

Uranus and Neptune continue to be visible in the early evening sky. Find them shortly after dark -Uranus in the constellation Pisces and Neptune in the constellation Aquarius. You will need to observe these two planets early, before they set this month. Neptune is best viewed just after dark during the first two weeks of the month, and Uranus is best viewed after dark but before 9:00 p.m. all month.

You will need a telescope to easily observe these two faint planetary disks.

Find a location chart for Uranus and Neptune at this link.



http://www.skyandtelescope.com/wp-content/uploads/WEB_UrNep_Finders.pdf



The planets Jupiter, Mars, Saturn and Venus can be found all month in the south to southeast pre-dawn and dawn skies.

All 4 bright planets should be very easy to spot in this early morning lineup along the ecliptic.

Moving to the west side of the Sun (following its January 14th inferior conjunction), Mercury will join Jupiter, Mars, Saturn and Venus at dawn by month-end. Find Mercury rather low in the east-southeast twilight zone during the last week of the month.

This will be the first time in 11 years that all 5 visible planets will be observable simultaneously!



The bright stars Spica and Antares are located 263 and 604 light years, respectively,

behind the planets.

All month in the dawn skies, find 4 bright naked-eye planets aligned along the ecliptic.

The view from Asheville, NC about one hour before sunrise on Jan. 15th

Horizon



Venus Passes Saturn in the Dawn Skies

At dawn on January 9th, the bright planet Venus will appear close to the fainter planet Saturn.

In another week, Venus will appear well below Saturn, as it orbits toward the back side of the Sun, while Earth’s solar orbit will cause Saturn to appear higher in the sky.

Saturn is some 883 million miles behind Venus! Image courtesy of Sky & Telescope

Conjunction of Venus and Saturn


January 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 0.8

AUs

Sagittarius & Capricornus

8.4 0.7 Reaches inferior

conjunction on

Jan. 14th

Venus 1.2

AUs

Scorpius, Ophiuchus & Sagittarius

13.3 -4.0 Prominent as

the “morning

star” this month

Mars 1.4

AUs

Virgo & Libra

6.2 1.1 Positioned in

the morning sky

all month




Constella-tion(s)


Avg. Mag-

nitude

Comments

Page 2 of 3

Jupiter 4.8 AUs Leo 40.7 -2.3 Rising in the east

by 9:05 p.m. at

month end.

Saturn 10.7

AUs

Ophiuchus 15.6 0.5 Can be found in

the SE dawn sky

all month

Uranus 20 AUs Pisces 3.5 5.8 Observe it early

in the evening

this month




Constella-tion(s)


Avg. Mag-

nitude

Comments

Page 3 of 3

Neptune 31 AUs Aquarius 2.2 7.9 Sets soon after

dusk this

month


January 2016 Sky EventsCatch all 5 Naked-eye Planets and the Moon in the Dawn Skies

The view from Asheville, NC at 6:45 a.m. EST on Sunday, January 31st, about 46 minutes before sunrise. Notice the gibbous Moon above Mars. Use binoculars to help you locate fainter Mercury near the horizon.

Horizon

Dawn on Jan. 31st

5 planets from left

to right along the

ecliptic: Mercury,

Venus, Saturn,

Mars & Jupiter.


The Moon – January 2016

Unless otherwise indicated, all times are EST

** The “Wolf Moon”

Last Quarter 2nd 12:30 a.m.

New Moon 9th 8:30 p.m.

First Quarter 16th 6:26 p.m.

Full Moon** 23rd 8:46 p.m.

Last Quarter 31st 10:28 p.m.



On January 2nd, Saturday, the Earth reaches “perihelion” -closest approach to the Sun for the year.The word “perhelion” is from the Greek: “peri” meaning near and “helios” meaning Sun.Earth is some 3 million miles closer (or one part in 30 closer) at perihelion than at the farthest point in its elliptical orbit (aphelion) in early July.Yet we experience our coldest weather in the northern hemisphere during January.

It’s the Earth’s 23½° axial tilt combined with its orbit, not its distance from the Sun, that causes the seasons.In January the northern hemisphere is pointed away from the warmth of the Sun.



Quadrantid Meteor Shower Peaks

Image courtesy of Sky & Telescope

This year’s Quadrantid Meteor Shower is predicted to peak in the Asheville area during the early pre-dawn hours of Monday - January 4, 2016.

Under clear dark open skies, you can expect from 60 to 200 meteors per hour, but these numbers are difficult to predict reliably.

A 30% illuminated waning crescent Moon will rise about 2:26 a.m. on Jan. 4th, but it should not create a significant problem for the meteor observing.

The source of this meteor shower is the debris from an object labeled 2003 EH1 – an asteroid or possibly an extinct comet.

Comet Catalina in the early morning skies all month



• Discovered in 2013 by observations of the Catalina

Sky Survey, Comet C/2013 US10 (Catalina) has

steadily brightened. This new comet comes from

the Oort Cloud in the outer regions of the solar

system.

• Will it become visible to the unaided eye?

• Comet predictions are challenging, but Catalina is

presently brightening and forecasted to reach

magnitude 4.8 this month – visible to the naked

eye under clear dark skies.

• Its closest approach to Earth (some 67 million

miles) occurs on January 12th.

• Observing Catalina will require an early rise as it

will be visible in our pre-dawn/dawn skies.

• Comet Catalina passes very close to the bright star

Arcturus in the constellation Bootes on Jan. 1.

Telescopic image of

Comet Catalina taken in early

August 2015

Comet Catalina’s path as viewed from the ecliptic plane on Jan. 12, 2016



Image courtesy of Sky & Telescope

Having rounded the Sun below the Earth’s orbital plane, Comet Catalina continues its journey back to the Oort Cloud in the outer reaches of our solar system.

Sun


January 2016Sky Events

Comet Catalina’s Path

through the January

Pre-Dawn Skies

Chart courtesy of Sky & Telescope

In January Comet Catalina is leaving the inner solar system, as it continues its long journey back toward the Oort Cloud. Follow this comet through our northeast skies this month.

be


January 2016Sky Events

Comet Catalina near the zenith in the early morning

of January 12th

Horizon

Comet Catalina

The 4 planets Jupiter, Mars, Venus & Saturn join Comet Catalina in the dawn skies. Using binoculars or a small telescope will help in locating this faint comet.

The comet is located just off the end star (Alkaid) in the handle of the Big Dipper.

On January 12th Catalina is at its closest approach to Earth –about 67 million miles away.

Horizon

The view from Asheville, NC looking southeast about 6:00 a.m. EST on January 12th

Horizon



The Moon Occults the Star Aldebaran

The waxing gibbous Moon will occult (pass in front of) the bright, orange, giant star Aldebaran on the night of January 19th – Tuesday.

Aldebaran (in the constellation Taurus) is the brightest star that the Moon can pass across;Aldebaran shines at magnitude +0.9.

With binoculars or a small telescope, watch this star disappear from view behind the dark limb of the Moon about 9:21 p.m. EST, and reappear on the other side, from the illuminated limb, about 10:17 p.m. EST – a 56 minute stellar “blackout”. These times are for Asheville, NC.



The Gibbous Moon Occults the Star

Aldebaran on Tuesday, January 19th

Look to the south-southwest into the constellation Taurus to observe this event.

All times are approximate for Asheville, NC using EST.

Aldebaran is 65 light years behind the Moon!

Aldebaran

Aldebaran

Disappearance

about 9:21 p.m.

Reappearance

about 10:17 p.m.

january 2016-aca-sky

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