Skywatchers Guide

Skywatcher's Guides

Flandrau’s Observatory is operated entirely by volunteers. Please call ahead to see if the observatory is open (generally Thurs-Sat 7pm – 10pm). Our astronomer volunteers will help you experience the 16-inch telescope as well as answer your questions about the night sky.

Written by: Lucas Snyder (Flandrau Planetarium Operator)
Images contributed by: Tim Van DevenderAlistair Symon (Flandrau Telescope Operators), Nine Planets, and Students for the Exploration and Development of Space (SEDS)

Navigationphoto by Tim Van Devender

Stars and Constellations

In December, the summer constellations are still visible for the first few hours of the night towards the west.  The Summer Triangle is still fairly high, with Vega heading to the west-northwest, Deneb closest to the zenith, and Altair in the west-southwest.  The center of the Milky Way is now below the horizon, but there is still a good portion of our galaxy we can see streaking high across the sky. The fall sky is now very prominent, getting high in the eastern sky.  The "W" of Cassiopeia is very high in the north-northeast. In the absence of the Big Dipper (part of our spring sky) Cassiopeia can be used to locate the north star: The top (open side) of the "W" faces to the north, so in that direction look for a star about the same brightness as the main stars in Casssiopeia, and that will most likely be Polaris.  Next, the Great Square of Pegasus is nearly in the middle of the sky.  Andromeda is nearby in the northeast, with Perseus just below.  There is also a fairly bright star called Fomalhaut in the south, though its constellation Piscis Austrinus is not easy to distinguish.  Finally, the winter sky is beginning to come up along the eastern horizon.  Taurus the bull is now up in the east with the bright star Aldebaran and the Pleiades (aka the seven sisters or Subaru) star cluster.  Auriga the charioteer is also up in the northeast, with the bright star Capella.

 

In January, the summer constellations are now very low in the west.  Deneb is the highest point of the Summer Triangle in the northwest, with Vega below near the horizon, and Altair more towards the west.  The Milky Way continues to streak across the sky, though the summer portion is now giving way to the winter portion.  The fall constellations are now right in the middle of the sky.  More of the winter constellations are now up, most notably Orion the hunter in the east below Taurus.  Gemini the twins are also up in the east-northeast just below Auriga.

 

 Interesting Stars Visible in December and January (during observatory hours)

 

Name / Designation

Apparent Magnitude
(lower = brighter)

Distance

(light-years)

Notes

Sirius

-1.44

8.6

 

Vega

0.03

25

 

Capella

0.08

42

 

Rigel

0.18

770

 

Procyon

0.4

11

 

Betelgeuse

0.45

427

 

Altair

0.76

17

 

Aldeberan

0.87

65

 

Pollux

1.16

38

 

Markab

1.25

140

 

Deneb

1.25

3230

 

Castor

1.58

52

 

Polaris

1.97

431

 

Alpheratz or Sirrah

2.07

97

 

Mirach

2.07

199

 

Algol

2.09

93

variable star

Enif

2.38

670

 

Almak

2.1 / 5.0 & 6.3

355

 triple star system w/ 64 yr orbit

Albireo

3.2 / 5.8 & 5.1

390 / 380

 possibly a triple star system

Eta Cassiopeiae

3.5 / 7.4

19

480 yr orbit

 

Solar System

Mercury is visible in the evening after sunset at the beginning of December, but will be passing between us and the sun by the end of the month.  It will then be visible in the morning sky before sunrise by mid-January.

 

Venus continues rising higher in the west each evening after sunset, reaching its highest point in mid-January.

 

Mars remains visible in the southwest after sunset, but will set earlier and earlier each night..

 

Jupiter rises earlier and earlier each morning, eventually rising at midnight by the end of January.

 

Saturn passes behind the sun in December and will again be visible in the morning sky in January.

 

Calendar of Night Sky Events

 

12/07/16

First Quarter Moon.

12/10/16

Saturn at conjunction. On the far side of the sun.

12/10/16

Mercury at greatest eastern elongation. Visible in the evening after sunset.

12/13/16

Peak of Geminids meteor shower.

12/13/16

Full Moon.

12/20/16

Last Quarter Moon.

12/21/16

Southern Solstice. Official beginning of our winter.

12/28/16

Mercury at inferior conjunction. Passing between us and the sun.

12/28/16

New Moon.

12/31/16

Appulse of Mars and Neptune. Separated by only 0.02°.

01/03/17

Peak of Quadrantids meteor shower.

01/04/17

Earth at perihelion. Our closest approach to the sun for the year.

01/05/17

First Quarter Moon.

01/09/17

Appulse of Mercury and Saturn. Separated by 6.8°.

01/12/17

Full Moon.

01/12/17

Venus at greatest eastern elongation. Visible in the evening after sunset.

01/12/17

Appulse of Venus and Neptune. Separated by 0.4°.

01/19/17

Mercury at greatest western elongation. Visible in the morning before sunrise.

01/19/17

Last Quarter Moon.

01/27/17

New Moon.

01/29/17

Comet Honda-Mrkos-Pajdusakova at brightest. Expected to be visible in the morning before sunrise.

 

Deep Sky

The summer Milky Way is now partially below the horizon at the beginning of the night, but the winter Milky Way is getting more and more prominent.  There are many open star clusters that can be seen with only binoculars scanning this part of the sky.  For example we have the asterism of the Coathanger between Aquila and Cygnus in the fainter constellation of Vulpecula.  The Pleiades (M45) is visible naked-eye in the east just above the face of Taurus which itself is another cluster called the Hyades.  We also have the Double Cluster in Perseus high in the north-northeast.  Finally, the constellation of Auriga in the northeast contains M36, M37, and M38 in close proximity.

 

There aren't as many globular clusters we can see this time of year, but there are still a few.  M15 is visible near the head of Pegasus in the west-southwest.  The next brightest one is M2 in Aquarius to the southwest.

 

For nebulae, we have several in the plane of the galaxy, one of which is the North America Nebula (C20) to the west-northwest in Cygnus.  The spectacular Orion Nebula (M42) is now just rising at the beginning of the night in the east. For planetary nebulae we have the Ring Nebula (M57) in Lyra, the Dumbell Nebula (M27) in Vulpecula, and the Blue Snowball (C22) in Andromeda.

 

And now the galaxies:  Our neighbor the Andromeda Galaxy (M31) is now very high in the middle of the sky and is visible on dark nights with the naked eye.  Also nearby is the Triangulum Galaxy (M33), visible with binoculars.

 Interesting Deep Sky Objects to Observe during December and January (during observatory hours)

Designation

Name

Apparent

Magnitude

Apparent Size

Distance

(light-years)

Type

Messier 45

Pleiades

1.6

110'

440

open cluster

Messier 31

Andromeda Galaxy

3.4

3° x 1°

2,900,000

spiral galaxy

Messier 44

Beehive Cluster

3.7

95'

577

open cluster

Messier 42

Orion Nebula

4

85' x 60'

1400-1600

diffuse nebula

Messier 33

Triangulum Galaxy

5.7

67' x 42'

3,000,000

spiral galaxy

NGC 7293

Helix Nebula

7.3

16'

450

planetary nebula

Messier 27

Dumbbell Nebula

7.4

8' × 6'

1,250

planetary nebula

NGC 7009

Saturn Nebula

8

36"

2,400

planetary nebula

Messier 81

Bode's Galaxy

8.5

21'

1,200,000

spiral galaxy

Messier 57

Ring Nebula

8.8

1'

2,300

planetary nebula

Messier 82

Cigar Galaxy

9.5

14'

1,200,000

galaxy

 

Frequently Asked Questions – What's all the hype about gravitational waves?

Several months ago you may have heard about the first direct observation of gravitational waves.  It was the result of two black holes merging together, sending ripples out through space.  The event was actually detected in September 2015 by the LIGO and Virgo collaborations, and it was announced about five months later.  So why is this such a big deal?

Since Einstein's formulation of general relativity in 1916, the possibility of gravitational waves has been theoretically considered.  But even Einstein himself doubted that we would ever be able to detect them due to their astonishingly miniscule effect.  But if they could be detected, they would allow us to "see" events that may not emit any visible light.  So for many years we have been working on improving the precision of our instruments to be able to detect this tiny signal.

The signal detected was indeed small:  The ripple amounted to only a 25-quintillionth of a percent change in the length of the detector arm, approximately equivalent to the with of a human hair compared to the distance to Proxima Centauri.  The signal has been determined to have come from the merger of two black holes about 1.4 billion light years away.

Right now we don't have the ability to determine exactly what direction these waves came from, but certainly now that we know these waves can be detected we will build more and better detectors which will give us the ability to resolve this information.

If you have any questions you'd like me to answer in the next issue of SWG, please let me know.  I'm also happy to take suggestions or comments, and also pictures if you'd like to send them.  Happy viewing!

 

Table of Images (Click on an image to expand)

Sketches and Images - Image Credit (Tim Van Devender)

Mars

Mars

Saturn

Saturn

Jupiter

Jupiter

The Moon

The Moon

Jupiter and Io Moon Shadow

Jupiter and Io Moon Shadow

Messier 45 (Pleiades)

M45

NGC 884 and NGC 869 - Perseus Double Cluster

NGC 884 and NGC 869 - Perseus Double Cluster

NGC 2024 - The Horsehead and Flame Nebulae

NGC 2024 - The Horsehead and Flame Nebulae

NGC 2237 - The Rosette Nebula

NGC 2237 - The Rosette Nebula

NGC 2264

NGC 2264

Images from Alistair Symon
Messier 27 (Dumbbell Nebula)

M27

Mssier 31 (Andromeda Galaxy)

M31

Messier 33 (Triangulum Galaxy)

M33

Messier 45 (Pleiades)

M45

Messier 57 (Ring Nebula)

M57

Images from Nine Planets
Jupiter

Jupiter

The Moon

The Moon

Images from SEDS
Messier 13 (Hercules Globular Cluster)

M13

Messier 15

M15

Messier 27 (Dumbbell Nebula)

M27

Messier 31 (Andromeda Galaxy)

M31

Messier 33 (Triangulum Galaxy)

M33

Messier 44 (Beehive Cluster)

M44

Messier 45 (Pleiades)

M45

Messier 57 (Ring Nebula)

M57

NGC 7009 (The Saturn Nebula)

NGC 7009

NGC 7293 (The Helix Nebula)

NGC 7293

 

Bibliography

Cornelius, Geoffrey. The Starlore Handbook: an Essential Guide to the Night Sky. San Francisco, CA: Chronicle, 1997. Print.

Ottewell, Guy. Astronomical Calendar 2012. Raynham, Mass: Universal Workshop, 2011. Print.

Ottewell, Guy. Astronomical Calendar 2013. Raynham, Mass: Universal Workshop, 2012. Print.

Ottewell, Guy. The Astronomical Companion. 2nd ed. Raynham, Mass: Universal Workshop, 2010. Print.

 

Astronomy Magazine. February 2013. Volume 41, No 2.

Astronomy Magazine. February 2013. Volume 41, No 3.

Sky & Telescope. February 2013. Volume 125, No 2.

Sky & Telescope. March 2013. Volume 125, No 3.