SKY REPORTER: Record Setting Asteroid Encounter

by Steve Beyer on

Hayden Planetarium Blog

Record Setting Asteroid Encounter

Meteor Crater
 
Credit: Shane Torgerson

NASA predicts that on Friday, February 15th, a space rock designated 2012DA14, half as big as a football field, will pass just 17,200 miles over Earth’s surface. Orbit calculations indicate there is no danger of a collision with Earth. 

At about 2:26 pm Eastern Time Friday February 15, asteroid 2012 DA14 will pass about 17,200 miles above Earth. It will then be nearer to the planet than the zone of geo-synchronous satellites used for communications, but no collisions with Earth or any of these satellites are predicted.

Don Yeomans of NASA’s Near Earth Object Program at the Jet Propulsion Laboratory described the event in the following terms: "This is a record-setting close approach. Since regular sky surveys began in the 1990s, we've never seen an object this big get so close to Earth." "2012 DA14 will definitely not hit Earth", Yeomans emphasizes. "The orbit of the asteroid is known well enough to rule out an impact."

This rocky visitor appears to be similar in size to an iron asteroid that blasted out famous 4,000 ft. wide Meteor Crater in Arizona 50,000 years ago, and also in the size range of an object that disintegrated high over Siberia in 1908 causing the immense "Tunguska Event" blast.

Sky Data

On Friday February first, sunrise in New York City is at 7:05 a.m. Eastern Time. That evening the Sun, located in Capricorn, sets at 5:13 p.m.

Friday February 15th, sunrise is at 6:49 a.m. and sunset occurs at 5:31 p.m.

On the last day of the month, Thursday the 28th the Sun is in Aquarius, rising at 6:31 a.m. and setting at 5:46 p.m. The altitude of the sun at solar noon, its maximum daily elevation, increases during February from 33 degrees of arc on the first to 42 degrees on the 28th. The duration of daylight during February increases by one hour and seven minutes.

During February average overnight temperatures recorded by Belvedere Castle in Central Park rise from 27 degrees Fahrenheit on the first to 31degrees on this month’s last day.

Principal Phases of the Moon are:

Last Quarter Sunday February 3 at 8:56 a.m.
New Moon Sunday February 10 at 2:20 a.m.
First Quarter Sunday February 17 at 3:31 p.m.
Full Moon Monday February 25 at 3:26 p.m.

Sky Cast

Mercury is low in the twilight sky of evenings at the start of February. It sets at 6:01 p.m. in Capricorn on the first of the month, 48 minutes after sunset. It is at greatest eastern elongation on the 16th. On the last day of February Mercury is within boundaries of the constellation Aquarius and sets at 6:25 p.m., 39 minutes after the Sun.

Venus is in southeastern predawn skies of February, rising in Sagittarius 37 minutes before the Sun at the start of the month. On the 28th it rises in Aquarius at 6:21 a.m., just 10 minutes before the Sun.

Mars, in Aquarius, may be seen low in the southwest briefly during early evenings throughout February. On the first of the month it sets at 6:35 p.m. and by month’s end Mars exits the sky at 6:37 p.m.

Jupiter, still in Taurus, is a bright beacon to unaided eyes and a wonderful telescopic sight during evenings throughout this month. On February first the Solar System’s largest planet sets at 2:47 a.m. and at month’s end sets one hour and eight minutes after midnight.

During February Saturn is in Libra. On the first of the month it rises above the east-southeastern horizon at 12:30 a.m. and on the morning of the 28th rises at 10:36 p.m.

Uranus is in Pisces all month. On the first night of February it sets at 9:36 p.m. and at month’s end it will set at 7:56 p.m.

Neptune remains in Aquarius setting at 6:47 p.m. on February 1st, and is in conjunction with the Sun on February 21, thereafter moving into the predawn sky and rising at 6:18 a.m., 13 minutes before the Sun, on February 28th.

During the post-midnight hours of Saturday February second the waning gibbous moon is between first magnitude star Spica in Virgo and somewhat brighter Saturn in Libra.

Early the next morning the Moon may be seen about four degrees south of Saturn.

Low in the west-southwestern sky of early evening Monday February fourth first magnitude Mars is about half a degree of arc to the left of eighth magnitude Neptune.

At 2:09 am on Thursday February 7th the waning crescent Moon is at perigee, closest point in its orbit to Earth.

The early evening of Friday the 8th Mercury is just one-third of a degree of arc from Mars. This is less than the apparent diameter of the Moon’s disk.

Monday the 11th at about 5:30 pm the thin crescent Moon may be seen about six degrees to the upper right of Mercury, with that planet being in turn 2.5 degrees directly above Mars.

During the nights of February 17th and 18th the Moon, just past its first quarter phase, is in the vicinity of Jupiter as well as the Pleiades and Hyades star clusters, and also Aldebaran the brightest star in Taurus.

Sunday evening February 24th, just after the fading of evening twilight, Mercury may be seen low in the west-southwest about four degrees of arc to the upper right of Mars.

February’s Full Moon, known traditionally as the Snow Moon, appears just south of the constellation Leo on the night of Monday the 25th.

Early on the morning of February the 28th Venus is located less than one degree of arc from Neptune.

Sky Lore

Evenings of February present us with some of the most vivid star gazing opportunities of the year. Star fields around Orion are centered in the middle of the southern sky during hours soon after sunset. Constellations related to Orion the Hunter in classical sky mythology include his faithful dogs Canis Major and Canis Minor, the charging Bull Taurus, and Lepus, the Hare. By the middle of this month the coldest weeks of the winter usually have passed and we are more inclined to linger outdoors watching celestial highlights.

This year, except for the Moon, Jupiter is the brightest member of this bright display. A quick glance upward, providing buildings or trees don’t get in the way is usually all that is needed to spot that planet, looking much like a vivid non- twinkling star. Jupiter’s disk is big enough so as to provide a constant beam of light that reaches our eyes despite minute atmospheric disturbances that make actual stars appear to twinkle. Nevertheless, the Jovian disk is still too small to appear as anything but a point of light to our unaided eyes.