Bakersfield Night Sky - March 16, 2013

By Nick Strobel

Tickets went on sale yesterday for the William M Thomas Planetarium's last show of the spring semester, the ever-popular Black Holes on April 18th. Since tickets can now be purchased online, if you want to see the show, then buy your ticket TODAY from the link posted on the Planetarium's homepage.

This past week, the Student Government Association at Bakersfield College sponsored a blood drive at the college.

Their blood drive was a huge success, but if you weren't able to donate then and would like some stars with your blood donation, then come to the Houchin Community Blood Bank star party sponsored by the Kern Astronomical Society on Monday, March 18th. The blood drive will be at Houchin's new facility at 11515 Bolthouse Drive (west of Buena Vista Road and south of White Lane across from St John's Lutheran Church).

The blood drive is from 5 to 7 PM with star-gazing through the KAS telescopes continuing until 8 PM.

One pint per person please, or you may be seeing stars without the telescopes!

The following Wednesday on March 20th marks the official start of the season of spring with the vernal equinox.

The spring equinox for the northern hemisphere is when the Sun crosses the celestial equator (projection of the Earth's equator onto the sky) heading northward. Since the equinox happens when the Sun reaches a particular point with respect to the celestial equator, we have that nailed down very precisely: 4:02 AM Pacific Daylight Savings Time.

For the rest of the spring season, the Sun will move further and further north of the celestial equator, getting higher and higher at mid-day with each passing day and the amount of daylight will grow ever longer up to the June solstice.

As I write this, Comet PanSTARRS (C/2011 L4) is becoming visible for us in the northern hemisphere. As shown in the first star chart below, it is very low in the west just after sunset.

To the naked eye it will look like a faint jet contrail with the tail pointing away from the Sun. Its orbit is nearly at a right angle with respect to the Earth's orbit so those in the southern hemisphere have been able to see it approach the Sun and we'll see it when it is at perihelion (closest point to the Sun) and then moving on out away from the Sun.

Perhaps by then, the comet's dust tail will become more prominent and distinct from the ion tail. The comet will, of course, be much better through a good pair of binoculars or the KAS telescopes at the KAS star party/blood drive.

Comet PanSTARRS (C/2011 L4) on March 13th at 7:52 PM at an altitude of about 11 degrees through the lovely Bakersfield air.

If you would like to see views of the the comet's orbit from various vantage points just outside the Earth's orbit, go to the Comet PanSTARRS Orbit page on the Planetarium's website.

On that page, you will see how the comet's orbit is oriented with the Earth's position at the time it passes near the Sun and why we in the northern hemisphere have to wait until near its perihelion passage and afterward for us to have a good view of the comet.

Tonight the Waxing Crescent Moon will be below the Pleiades star cluster that is at the shoulder of Taurus - see the first star chart below. Tomorrow night the Moon will be just below very bright Jupiter - a nice view through binoculars.

On the night of the KAS star party, the Moon will be one day before first quarter phase at Taurus' horn. The Moon will be full on the night of March 26/27.

Jupiter is already high up in the southwest at sunset just right of the west horn of Taurus. By the end of the month it will have moved eastward so that it is just left of the west horn.

Jupiter takes almost twelve years to orbit the Sun, so it does appear to drift slowly with respect to the stars, roughly one zodiac constellation per year.

Saturn rises up in the east just before 11 PM. It is near the western tip of Libra and it is undergoing retrograde motion, or slowly moving westward back toward Virgo over the next few months. In tonight's sky Saturn and Libra will be in the south at around 4 AM.

The second star chart below shows that view.

Want to see more of the stars at night and save energy? Shield your lights so that the light only goes down toward the ground. Visit the Dark Sky International website for more info.

• Nick Strobel
• Director of the William M Thomas Planetarium at Bakersfield College
• Author of the award-winning website www.astronomynotes.com