Seeing Stars with James Wooten: March 2013

Jupiter is almost overhead at dusk, but now a little toward the west. Face high in the west at dusk and look for the brightest thing there (unless the Moon is also there), as Jupiter outshines all stars we ever see at night.

Saturn remains in the morning sky this month.  Look for it in the south/southwest at dawn.

Venus and Mars are on the far side of the Sun and out of sight this month. Venus passes behind the Sun (at superior conjunction) on March 28.

Sky Map: March 2013

Brilliant winter stars shift toward the southwest during March. Dazzling Orion is almost due south at dusk. His three-starred belt is halfway between reddish Betelgeuse and bluish Rigel. Orion’s belt points up to Aldebaran in Taurus the Bull. This winter and spring the Bull also contains Jupiter.

To Orion’s upper left are the twin stars Castor and Pollux, marking the heads of Gemini, the Twins. You can find Sirius, the brightest star we ever see at night, by drawing a line from Orion’s belt towards the horizon. To Orion’s left, about level with Betelgeuse, is Procyon, the Little Dog Star.

From Sirius, look a little bit to the right and then straight down to the horizon. If your southern horizon is clear of clouds and tall earthly obstacles, you’ll see Canopus, the second-brightest star ever visible at night. This star is so far south that most Americans never see it and many star maps made in the USA omit it. (You must be south of 37 degrees north — the latitude of the USA’s Four Corners — for Canopus to rise). As you view Canopus, keep in mind that the sky we see depends on our latitude as well as on time of year and time of night.

Joining the winter stars are stars of spring rising in the east.  Look for Leo, the Lion at dusk. Later in the evening, extend the Big Dipper’s handle to ‘Arc to Arcturus’ and then ‘speed on to Spica’; these stars rise at about 10 p.m. in early March but by 9 p.m. on the 31st.

March 2013 evening skies feature an extra special object — comet Pan-STARRS, our first naked-eye comet since Hale-Bopp back in 1997!  Observers south of the equator have already been observing Pan-STARRS, but the comet has been invisible to us because it has been south of the Sun in our sky. That is beginning to change as Pan-STARRS nears its closest approach to the Sun late on March 9.

Like all comets, Pan-STARRS will be at its brightest as it comes closest to the Sun.  At the same time, Pan-STARRS will be coming up through the plane where the planets orbit and thus will be much easier for us to see in mid-March. You can start looking in western twilight as early as March 7 if you have a low, unobstructed horizon. The comet may be slightly easier to see on March 12 and 13, when the crescent Moon is nearby. Once Pan-STARRS appears in the western dusk sky, it shifts towards the north (to the right as you face west) each night, until it fades and returns to the Sun’s glare in April.

As always, scientists are unsure how bright Pan-STARRS will get.  It now seems that it won’t be as spectacular as was Hale-Bopp in 1997. However, southern observers are seeing it naked-eye, and so should we. The comet could be about as bright as average stars such as those in the Big Dipper, but may be dim enough that you need a dark site to see it, especially once the Moon gets bigger.

Ultimately, though, we’ll have to wait and see. Sky and Telescope has a helpful finder chart here.

Moon Phases in March 2013:
Last Quarter                  March 4, 3:54 pm
New                               March 11, 2:53 pm
1st Quarter                    March 19, 12:26 pm
Full                                March 27, 4:29 am

At 6:01 a.m. on Wednesday, March 20, the Sun is directly overhead at the equator.  This therefore is the vernal (spring) equinox, a day when everyone on Earth has the same amount of daylight. After this date, our gradually lengthening days become longer than our nights, and we go into springtime. South of the equator, days have been shortening.  For them, this equinox marks the point when night becomes longer than day, and the onset of autumn.

Sunday, March 10, is the second Sunday of this month. Therefore, Daylight Saving Time begins at 2 a.m. this morning (the time officially goes from 1:59 to 3 a.m.)  Don’t forget to spring forward by advancing all clocks one hour on Saturday night, March 9!

On most clear Saturday nights at the George Observatory, you can hear me do live star tours on the observation deck with a green laser pointer.  If you’re there, listen for my announcement. This Spring Break, the George will be open to the public on Tuesday night, March 12, and Thursday night, March 14.

To enjoy the stars in any weather from the comfort of the HMNS Planetarium, click here for a full schedule.

Go Stargazing! March Edition

Saturn is up all night long by month’s end.  On Mar. 21, Earth passes between the sun and Saturn.  This alignment is called opposition because it puts Saturn and the sun on opposite sides of the Earth.  As a result, Saturn rises at dusk and sets at dawn on this date.  Look for Saturn to rise due east around 8:00 p.m. tonight. It will rise just a little bit earlier each night.

Venus enters the evening sky by the end of March.  As March opens, Venus is still setting during twilight, making it hard to notice at dusk.  By the end of the month, though, Venus has come out from behind the sun far enough for us to notice it clearly.  Face west at dusk and look for a point of light that outshines everything in the sky but the sun and the moon.

Mars has become an evening object.  It is now already up in the east-northeast by dusk.  On Jan. 29, Mars came to opposition as Earth passed between Mars and the sun, putting Mars in our sky all night long.  Earth is now pulling ahead of Mars on its faster orbit.  As a result, Mars is slightly dimmer each night for the rest of 2010.  However, during March, Mars remains brighter than average, and thus remains easy to see.  Look high in the southeast as dusk (due south by the end of the month) for a reddish point of light sort of in line with the two Dog Stars 

Jupiter is mostly out of sight this month.  Viewers with a very clear east-southeast horizon may notice Jupiter low in the sky at dawn by the end of March.  

STEAL ME FOR YOUR DESKTOP!! (The Bokeh Galaxy)
Creative Commons License photo credit: kevindooley

Dazzling Orion is high in the south.  His belt points up to Aldebaran, the eye of Taurus, the Bull.  The Dog Stars Sirius and Procyon are to Orion’s left.  Sirius is the brightest star we ever see at night.  Gemini, the Twins, are to Orion’s upper left.  Look for two stars of equal brightness less than 5 degrees (three fingers at arms’ length) apart.  These are Castor and Pollux, marking the twins’ heads.  High in the northwest is Capella, the sixth brightest star ever seen at night.  At dusk on March evenings, look below Sirius and a bit to its right for Canopus, the second brightest star we ever see at night. This star is in the keel (bottom) of the legendary ship Argo.  Canopus is so far south that most Americans never get to see it.  We, however, are far enough to the south that it barely rises for us, remaining low on the southern horizon.  

Meanwhile, spring stars are rising in the east.  A distinct backwards question mark shape outlines the mane and forepaws of Leo, the Lion.  Three stars forming a right triangle rise underneath; they mark Leo’s hindquarters.  The Big Dipper is once again fully risen at dusk. Later in the evening, you can extend its handle to ‘arc to Arcturus’ and then ‘speed on to Spica’.  These stars will be along the eastern horizon by 9:30 tonight, and even earlier later in the month.

Transit Lune/Saturne du 22 mai 2007
Creative Commons License photo credit:
ComputerHotline

Moon Phases in March 2010:

Last Quarter                  March 7, 9:43 p.m.

New Moon                      March 15, 4:02 p.m.

First Quarter                  March 23, 5:59 a.m. 

Full Moon                        March 29, 9:25 p.m.

At 12:33 p.m. on Saturday, Mar. 20, the sun is directly overhead at the equator.  This, then, is the vernal equinox. On this date, everyone in the world has the same amount of daylight and the same amount of night.  After this date, daytime is longer than night in the Northern Hemisphere, while night is longer than daytime in the Southern Hemisphere. 

Sunday, Mar. 14, is the second Sunday in March.  Accordingly, we spring forward into Daylight Saving Time at 2 a.m. that morning (1:59:59 a.m. is followed by 3:00:00 a.m.).  Don’t forget to set your clocks forward by one hour before going to bed Saturday night!

Go Stargazing! October Edition

Jupiter is the brightest thing in the evening sky this month, unless the Moon is out.  Face south-southeast and look for the brightest point of light there.  Remember, Jupiter outshines everything in the sky except the Sun, the Moon, and Venus, so if you’re looking in the right direction, you can’t miss it.

Conjonction Lune/Vénus
The Moon and Venus
Creative Commons License photo credit: ComputerHotline

Venus is still a dazzling morning star this month, but it’s now getting lower in the pre-dawn sky.  Look east right as day begins to break for the brightest thing unless the Moon is nearby.  Venus remains the ‘morning star’ for the rest of 2009.  Mars is now high in the east-southeast dawn. It is also brightening as the Earth approaches it. Saturn begins to emerge from behind the Sun, joining Venus in the morning sky.  Venus and Saturn are in conjunction on October 13. Look for Saturn between Venus and the horizon at dawn before that date, and slightly above Venus afterwards.  Elusive Mercury is also below Venus at dawn during the first half of the month.

The Big Dipper happens to be to the lower left of the North Star at dusk this month; you’ll need a clear northern horizon to get a good look at it.  Sagittarius, the Archer, known for its ‘teapot’ asterism, is in the southwest (Jupiter is in Sagittarius).  Look for the enormous Summer Triangle, consisting of the stars Deneb, Vega, and Altair, high in the west.   As familiar summer patterns shift to the west, the constellations of autumn take center stage.  The Great Square of Pegasus is high in the east at dusk.  The star in its upper left hand corner is also the head of Andromeda.  Facing north, you’ll see five stars in a distinct ‘M’ like shape—this is Cassiopeia, the Queen.  Her stars are about as bright as those in the Big Dipper, and she is directly across the North Star from that Dipper.  In fall, while the Dipper is low, Cassiopeia rides high.

Moon Phases in October 2009:

Full                                    October 4, 1:11 am
Last Quarter                  October 11, 3:56 am
New                                   October 18, 12:32 pm
1st Quarter                     October 25, 7:41 pm

Harvest Moon
Creative Commons License photo credit: Jay Scott Photography

The Full Moon of October 4 is the Full Moon nearest to the fall equinox.  Therefore, it is the Harvest Moon.  The ecliptic, which is the plane of the solar system set against the background stars, makes a very shallow angle with the horizon on late summer and early fall evenings.  Since the Moon orbits us in almost the same plane where Earth orbits the Sun, we see the Moon near the ecliptic.  When the ecliptic makes a shallow angle with the horizon, a shift in position along the ecliptic translates into less height above (or distance below) the horizon.  As a result, around the start of fall we see the Moon rise at about the same time for several days around Full Moon.  Harvesters often took advantage of this to keep working deep into the night.

November 1 is the first Sunday in November.  Therefore, Daylight Saving Time ends at 2:00 am that morning. (The time goes from 1:59:59 back to 1:00, such that the 1:00 am hour occurs twice.)  On Halloween night, remember to set your clocks back one hour and enjoy your extra hour of sleep!

Our annual Astronomy Day at the George Observatory is Saturday, October 24 this year.  From 3 p.m. to 10:30 p.m., we’ll be celebrating 400 years of modern astronomy and 20 years of the George Observatory.  Surf to www.astronomyday.org to read about all about the events going on that day.