Week of February 3, 2014

This is the Saint Louis Science Center’s NIGHT SKY UPDATE for the week of Monday, February 3.  All times are given as local St. Louis time (Central Standard Time).  For definitions of terminology used in the night sky update, click the highlighted text.

Information updated weekly or as needed.

Join us for our next star party, Friday, February 7, 2014 held in association with the St. Louis Astronomical Society. For details, see the information at the bottom of this page.

The Sun and the Moon

Sunrise is at 7:05 a.m. on Monday, February 3 and sunset is at 5:25 p.m. providing us with over 10 hours of daylight.  Even after sunset, the light from the Sun will still illuminate our sky for about one hour and 30 minutes.  This period of time is called twilight, which ends around 6:56 p.m. this week.  For those with a sun dial, solar transit or local noon occurs around 12:15 p.m. this week. 

Moonrise for Monday, February 3 occurs at 9:11 a.m.  Moonset will occur at 10:12 p.m.  On Monday the 3rd the Moon will be exhibiting a waxing crescent phase with roughly 20% of the lunar disk illuminated.  First quarter moon occurs on Thursday, February 6.

International Space Station (ISS) Observing

The next visible passes of ISS over St. Louis are all evening passes.  The best passes are on the evenings of February 6, 8 and 9.  Learn more about the passes and others this week in the table below.

Catch ISS flying over St. Louis in the evening hours starting Monday, February 3. 

Date

Mag

Starts

Max. altitude

Ends

Time

Alt.

Az.

Time

Alt.

Az.

Time

Alt.

Az.

04 Feb

-1.3

18:45:28

10

S

18:47:09

17

SE

18:47:09

17

SE

05 Feb

-1.4

19:32:31

10

SW

19:34:15

29

WSW

19:34:15

29

WSW

06 Feb

-3.1

18:44:11

10

SW

18:47:26

55

SE

18:48:18

40

E

07 Feb

-2.1

17:56:09

10

SSW

17:59:05

29

SE

18:02:02

10

ENE

07 Feb

-1.4

19:32:48

10

W

19:35:11

28

NW

19:35:11

28

NW

08 Feb

-2.5

18:44:00

10

WSW

18:47:14

48

NW

18:49:01

23

NNE

09 Feb

-3.2

17:55:23

10

SW

17:58:43

86

NW

18:02:04

10

NE

09 Feb

-0.7

19:33:42

10

WNW

19:35:40

16

NNW

19:35:40

16

NNW

10 Feb

-1.2

18:44:30

10

W

18:47:10

SS

NNW

18:49:18

13

NNE

 

Magnitude (Mag): The Measure of brightness for a celestial object.  The lower the value is, the brighter the object will be.

Altitude (Alt):  The angle of a celestial object measured upwards from the observer’s horizon.

Azimuth (Az):  The direction of a celestial object, measured clockwise from an observer’s location with north being 0°, east being 90°, south being 180° and west being 270°.

For information about ISS flyovers and other visible satellites, visit www.heavens-above.com

Detailed information regarding all unmanned exploration of our universe, missions past, present, and planned, can be found at Jet Propulsion Laboratories:

http://www.jpl.nasa.gov/

The Planets Visible Without A Telescope

Mercury

The closest planet to the Sun has started another evening apparition.  About 30 minutes after sunset Mercury will be about 10 degrees above the horizon.  Take a look at the elusive planet while you can as it now headed back towards the Sun in the sky.

Mars

Mars is now in the constellation Virgo and will rise around 11:00 p.m. this week.  For those awake around 12:00 a.m. look to the east and you will see a reddish-orange object low in the eastern skies.  Mars will be seen earlier each week as we start to catch up with it in our orbit.  Mars will be close to us again in 2014 reaching opposition on April 8, 2014.  Fans of Mars rejoice it is back and on its way to another close approach.

Jupiter

Jupiter is now rising as the Sun is setting.  For those with a clear eastern horizon look east roughly 30 minutes after sunset and you should see Jupiter shining brighter than any star in the sky.  As twilight fades you will see the bright stars Castor and Pollux just north of Jupiter.  Looking at these stars and then comparing them to Jupiter you will see that the stars are twinkling and Jupiter is not.  The twinkling you see is called scintillation which is a distortion of the stars light by Earth’s atmosphere.  Testing for scintillation is how you can distinguish stars from planets. 

Saturn

Saturn is now out of the glare of the Sun.  It rises by 1:27 a.m. and will be an easy target by 2:30 a.m.  Saturn is currently in the constellation Libra.  It forms a nice triangle in the sky with Libra’s two brightest stars Zubenelgenubi and Zubeneschamali.

Additional Solar System Object of Interest

Comet Lovejoy (C/2013 R1): Comet Lovejoy has been a treat for binocular observers since October 2013.  It reached perihelion on December 22, 2013 brightening to about 4.3 magnitude.  It still remains an object of interest for those with binoculars or small telescopes and can be seen in the morning skies by 5:00 a.m.

To locate Comet Lovejoy you will need to find the summer constellation Hercules in the eastern skies.  An easy way to find Hercules is to locate the Big Dipper, follow the curve of its handle to the bright star Arcturus.  This star marks the bottom of the kite shaped constellation Bootes.  Look to the east of the widest part of Bootes kite shape and you first find a U-shape of stars and further down you will see a bowtie shape of stars.  This bowtie shape is the body of Hercules.  Next locate the star Sarin also named Delta Herculis and the star Rasalhague in Ophiuchus.  Comet Lovejoy will be following a path between these stars through most of January 2014.  For a detailed map follow the link below. 

Now that Comet Lovejoy has passed perihelion it will continue to fade becoming more difficult to see each night.  It is currently listed at between 7.4 and 8th magnitude.  At 8th magnitude it has become a target for telescope users and will continue to get more difficult to see.  At 7.4 magnitude it may still be visible in large binoculars.  Either way good viewing conditions will be important for a chance to view this comet now.  Take a look at this comet before it fades from view. 

 

General Comet Information

http://cometchasing.skyhound.com/

http://cometography.com/

 

Star Charts Showing Comet Locations in the Sky

http://www.aerith.net/comet/weekly/current.html

http://freestarcharts.com/images/Articles/Month/Dec2013/Comet_Lovejoy/C2013_R1_Lovejoy_Jan_Finder_Chart.pdf

Constellation of the Month

Each month we will highlight one constellation and some of the objects that can be found within the boundaries of that constellation.  At the start of the month we will list only a few of these objects and each week we will add another to the list.  Some objects will be visible to the unaided eye and some may require a telescope.  Many of the objects listed will require a map of the sky to find or may require repeat observations to notice various properties.  Links to star charts and other information that will be useful in identifying the objects listed will be given at the end of each week’s section. 

For February the constellation we will highlight is Auriga the Charioteer.  Auriga is the northern most constellation in the asterism known as the Winter Triangle.  The brightest star in Auriga is Capella which is the 6th brightest star in the sky.  This time of the year Auriga has already begun to rise once the Sun has set and will be visible shifting from east to west.  Look for a home plate shaped grouping of stars north of Orion.

One story in Greek myth had Auriga representing Erichthoneus the lame son of Hephaestus and the Mother Earth.  It was believed the Erichthoneus invented the four horse chariot so he could get around easier.  Zeus admired Erichthoneus for his ingenuity and placed him in the heavens for eternity.    

The first object we will explore in Auriga is the open star cluster M37.  This is an open cluster that lies about 4,400 light years away containing roughly 500 stars that are about 300 million years old.  M37 has a Trumpler classification of I,1,r.  This is as good as it gets as this classification means M37 is a (I) bright detached globe of stars, (1) has numerous bright members and (r) has a rich field of stars. 

To find M37 look north of Orion for Auriga’s home plate shape of stars.  Once you can find this look between the two stars Beta Taurii and Theta Aurgae.  Grab a pair of binoculars and look about halfway between these two stars.  Just east of this midpoint you will see a faint cotton ball shaped source of light; this is M37.  Through a telescope you can start to resolve the 150 or so stars that are 12th magnitude or brighter.  With an age of 300 million years there are roughly 12 red giant stars in the cluster that have evolved off the their main sequence.  See if you can spot any of them

M37 is the brightest of a trio of star clusters that span across the southeast corner of Auriga.  The next few weeks we will cover the other two of the great open clusters in Auriga.  All three are great binocular targets.  For help finding M37 follow the link below.

http://iau.org/static/public/constellations/pdf/AUR.pdf

http://iau.org/static/public/constellations/gif/TAU.gif

http://messier.seds.org/m/m037.html

Supernova in M82

Recently a supernova was discovered in a neighboring galaxy called M82 or The Cigar Galaxy.  This galaxy is roughly 12 million light years away and is a member of the M81 group of galaxies.  The first to realize a star exploded in this galaxy were some astronomy students and their teacher who were exploring how to use a CCD camera to image the night sky.  There was a bit of astronomical serendipity as their observing session was being encroached upon by a bad weather.  Due to the approaching weather they had limited options for what to observe.  They chose M82 and were pleasantly surprised when they saw a star like object that normally is not seen in the galaxy.  Upon investigation they realized they had discovered a new supernova which is now designated Supernova 2014J.

Spectral analysis of the supernova shows a strong signature of silicon.  What this tells astronomers is that this is a Type Ia supernova.  This type of supernova involves two stars one of which is on its main sequence and the other is a white dwarf star.  White dwarf stars are the dense core of a star like the Sun that has evolved off its main sequence and is now fusing carbon and oxygen.  The byproduct of this is silicon.  As the white dwarf star orbits with its partner star it siphons material from its partner.  Due to the temperatures and pressures that develop, only 1.4 solar masses can be taken in this way.  Once it reaches this limit the star will explode in a supernova.  Type Ia Supernova like Supernova J2014 are useful to astronomers for measuring the distances to objects in space.  Since there is a set amount of mass that is gathered before the supernova there is a known amount of energy that is released.  With this they can determine the absolute luminosity and there for measure how far away the event is. 

To find M82 first locate the Big Dipper.  Follow a line from the stars Phecda to Dubhe and continue another roughly 10 degrees along this path.  Through a small telescope you will see two faint and fuzzy objects which are the galaxies M81 and M82.  Once you have located M82 you will need to carefully observe the fuzzy light source and you will see a faint star like object on its right side.  This is Supernova J2014.  Right now it is a safe bet that you will likely need a 6-inch telescope but the supernova may brighten enough to be within reach of 4-inch instruments.  If you find the supernova you will be looking at light from an explosion that occurred 12 million years ago as M82 is 12 million light years away.  Follow the links below for more information and a map of Ursa Major to help you locate M82 and Supernova J2014.

Update 2/3/2014

The supernova in M82 has reached its peak brightness at magnitude 10.5.  This puts the supernova within reach of backyard instruments.  The light from the 12 million year old explosion will eventually fade from view so see if you can spot this supernova before is fades forever.  

http://iau.org/static/public/constellations/gif/UMA.gif

http://www.skyandtelescope.com/observing/home/Bright-Supernova-in-M82-241477661.html

Our next Star Party will be held on Friday, February 7, 2014, from dusk until 10 p.m.

Weather permitting, the St. Louis Astronomical Society and the Science Center will set up a number of telescopes outdoors and be on-hand to answer your questions.  Telescope viewing begins at 8:00 p.m.  Regardless of the weather on February 7, join us indoors in our planetarium theater for “The Sky Tonight”.  Showtime is at 7 p.m.  There will also be two Laserium shows this night at 8:30 p.m. and 10:00 p.m.  Information for laser shows can be found at slsc.org/laserium

This free, indoor star program will introduce you to the current night sky, the planets, and the seasonal constellations. Doors open 15 minutes before show time. Shows begins at 7 p.m. Sorry, no late admissions due to safety issues in the darkened theater.

The St. Louis Astronomical Society hosts the monthly Star Parties at the Science Center which are held on the first Friday of each month. Our Monthly Star Parties are open to the public and free of charge.  For more information about the St. Louis Astronomical Society visit their website at www.slasonline.org

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