SKY REPORTER: Comet PanSTARRS Visits main content.


by Steve Beyer on


Sky Highlight

Comet PanSTARRS Map
Path of comet PanSTARRS in March 2013 for Northern Hemisphere observers.
Credit: Sky & Telescope

Comet PanSTARRS (C/2011 L4) is due in our western evening skies and should be worth looking for as evening twilight is fading about a half hour after sunset during middle weeks of March.

Early evenings from about March 7 through the 19th are expected to offer the best opportunities to view comet PanSTARRS. Binoculars are a definite plus as we pan across areas of western sky within 10 degrees of the horizon looking to spot the comet’s tail extending up from the direction of the recently set Sun. During the early evening of March 12th the comet is several degrees of arc to the left of a thin crescent moon. Early the following evening the wider lunar crescent is about 10 degrees above PanSTARRS.

Some estimates predict the comet’s extended tail will range in brightness between magnitudes zero and one during this period. That would make it about as vivid at maximum as stars such as Rigel, Capella, and Procyon, then fade somewhat to the brightness of first magnitude Betelgeuse and Aldebaran by mid-March. Other predictions suggest the comet will only be as bright as second magnitude stars of the Big Dipper. That being said, and keeping in mind the unpredictable nature of comets, we look forward to judging for ourselves the success of these predictions.

The following NASA video tells what we might expect from this comet:


Sky Data

Friday March first sunrise in New York City is at 6:29 a.m. Eastern Standard Time. That evening the Sun located in Aquarius sets at 5:47 p.m.

Friday March 15th, sunrise is at 7:07 a.m. and sunset occurs at 7:03 p.m., Eastern Daylight Time.

On the last day of the month, Sunday the 31st, the Sun is in Pisces rising at 6:41 a.m. and setting at 7:20 p.m. The altitude of the sun at solar noon, its maximum daily elevation, increases during March from 42 degrees of arc on the first to 54 degrees on the 31st. The duration of daylight this month increases by one hour and 21 minutes.

During March average nighttime temperatures recorded at Central Park increase from 31 degrees Fahrenheit on the first to 40 degrees on the 31st.

Principal Phases of the Moon are:

Last Quarter March 4
New Moon March 11
First Quarter March 19
Full Moon March 27

Sky Cast

At the start of the month Mars, Mercury, Venus, and Neptune are all close to the direction of the Sun and difficult to see due to twilight. On the other hand, Jupiter remains a vivid feature in Taurus, and Saturn is rising progressively earlier during evening hours.

Mercury, in Pisces, sets at 6:17 p.m. on March 1st. On the last day of the month it will have moved into the pre-dawn sky within boundaries of the constellation Aquarius and rises at 5:45 a.m.

Venus rises shortly before the Sun at 6:21 a.m. at the start of March. On the 31st it sets with the Sun in Pisces.

On the first of March Mars is in Aquarius, setting at 6:37 p.m. By month’s end it exits the sky at 6:36 p.m. in Pisces.

Jupiter sets at 1:04 a.m. on March 1st and by month’s end sets at 12:26 a.m.

During March Saturn is in Libra. On the first of the month it rises above the southeastern horizon at 10:36 p.m., and on the night of the 31st it rises at 9:32 p.m.

Uranus is in Pisces. On the first night of March it sets at 7:53 p.m. At month’s end it sets at 7:03 p.m.

Neptune remains in Aquarius rising at 6:14 a.m. on March 1st, and rises at 5:19 a.m. on March 31st.

During hours after midnight Monday March 4th, the Third Quarter Moon is in the vicinity of Antares and stars at the western part of the constellation Scorpius.

Daylight Saving Time starts at 2 a.m. the morning of Sunday March 10, when we set our clocks springing forward one hour.

During the night of Sunday March 17th, the waxing crescent Moon is near Jupiter in Taurus, when about two degrees of arc separate these bright objects.

The evening of Tuesday the 19th, the first quarter moon is in the constellation Gemini, near the most northerly point on the ecliptic. This night the Moon is also near the direction of comet ISON. Our ISON monitoring continues with that potentially brilliant comet still faint at 16th magnitude. During March it’s in the northern part of Gemini, about half way between brilliant stars Capella in Auriga and Procyon in Canis Minor.

Spring begins in the Northern Hemisphere at 7:02 a.m. the morning of Wednesday March 20th. At that time the Sun is directly over a point in the Republic of the Congo, on the equator at 16 degrees five minutes east longitude.

Tuesday March 26 our colleague Joe Rao will be at the Hayden Planetarium Space Theatre for his Astronomy Live lecture presenting “Spring Skies - A Comet is Coming!”

Wednesday the 27th the Full Moon is in the constellation Virgo, seven degrees west of first magnitude star Spica. March’s Full Moon is variously called the Full Storm, Sap, or Worm Moon, allusions to terrestrial goings on at this time of year.

During the nights of March 28th and 29th, the waning gibbous Moon will be near Saturn.

On the last day of March Mercury is at its greatest western elongation from the Sun, at an angular distance of 28 degrees.

Sky Lore

March brings the passing of magnificent constellations of winter as they settle towards the western horizon during hours after evening twilight. At these times decidedly less vivid constellations that typify springtime evenings are rising in the east. Stars currently in that portion of the sky are generally in a direction away from the disk of the Milky Way Galaxy and dramatic stellar concentrations in and around Orion.

Rather than dwelling on the end of one celestial season, let’s celebrate the return of beautiful although moderately bright star patterns such as the Sickle of Leo, the Big Dipper, and the rise of brilliant Arcturus, what I call the star of springtime!