Night sky guide for March 2017

Night sky guide for March 2017

The Sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world - March equinox - on March 20. This is the first day of spring (vernal equinox) in the northern hemisphere and the first day of fall (autumnal equinox) in the southern hemisphere. 

On March 10, Comet 2P/Encke will make its closest approach to the Sun, at a distance of 0.34 AU. On the same day, it is forecast to reach its brightest, at around magnitude 2.9.

The Moon will reach its full phase at 14:55 UTC on March 12. At this time in its monthly cycle of phases, the Moon lies almost directly opposite the Sun in the sky, placing it high above the horizon for much of the night. 

The Moon will pass close to the Sun on March 28 - New Moon - and become lost in the Sun's glare for a few days. This is the best time of the month to observe faint objects such as galaxies and star clusters because there is no moonlight to interfere. Over coming days, the Moon will rise and set an hour later each day, becoming visible in the late afternoon and dusk sky as a waxing crescent which sets soon after the Sun. By first quarter, in a week's time, it will be visible until around midnight.

  • March 1 - Close approach of the Moon and Mars - 21:22 UTC. The Moon and Mars will make a close approach, passing within 4°07' of each other.  The Moon will be at mag -10.6, and Mars at mag 1.3, both in the constellation Pisces. The pair will be too widely separated to fit within the field of view of a telescope but will be visible to the naked eye or through a pair of binoculars. The Moon will be 3 days old.

  • March 2 - IC2602 well placed for observation. Across much of the world the theta Carinae open star cluster (IC 2602, also known as the southern Pleiades) will be well placed for observation. It will reach its highest point in the sky at around midnight local time. At a declination of -64°24', it is easiest to see from the southern hemisphere but cannot be seen from latitudes much north of 5°N. At magnitude 1.9, IC2602 is visible to the naked eye, but best viewed through a pair of binoculars.

  • March 2 - Conjunction of the Moon and Eris - 00:52 UTC. The Moon and 136199 Eris will share the same right ascension, with the Moon passing 8°35' to the north of 136199 Eris. The Moon will be at mag -10.7 in the constellation Pisces, and 136199 Eris at mag 18.8 in the neighboring constellation of Cetus. The Moon will be 4 days old.

  • March 2 - Neptune at solar conjunction - 02:46 UTC. Neptune will pass very close to the Sun in the sky as its orbit carries it around the far side of the Solar System from the Earth. At closest approach, Neptune will appear at a separation of only 0°50' from the Sun, making it totally unobservable for several weeks while it is lost in the Sun's glare. At around the same time, Neptune will also be at its most distant from the Earth – receding to a distance of 30.94 AU – since the two planets will lie on opposite sides of the solar system. If Neptune could be observed at this time, it would appear at its smallest and faintest on account of its large distance. It would measure 2.2 arcsec in diameter. Over following weeks and months, Neptune will re-emerge to the west of the Sun, gradually becoming visible for ever-longer periods in the pre-dawn sky. After around six months, it will reach opposition, when it will be visible for virtually the whole night. 

  • March 2 - Conjunction of the Moon and Ceres - 22:44 UTC. The Moon and 1 Ceres will share the same right ascension, with the Moon passing 0°50' to the south of 1 Ceres. The Moon will be at mag -11.1, and 1 Ceres at mag 9.0, both in the constellation Cetus. The pair will be a little too widely separated to fit comfortably within the field of view of a telescope, but will be visible through a pair of binoculars.

  • March 4 - Conjunction of Mercury and Neptune - 05:25 UTC. Mercury and Neptune will share the same right ascension, with Mercury passing 1°07' to the south of Neptune. Mercury will be at mag -1.6, and Neptune at mag 8.0, both in the constellation Aquarius. The pair will be too widely separated to fit within the field of view of a telescope but will be visible through a pair of binoculars. 

Video courtesy NASA/JPL

  • March 5 - Moon at First Quarter - 11:34 UTC. The Moon will be prominent in the evening sky, setting around midnight. At this time in its monthly cycle of phases, it appears almost exactly half illuminated. Over coming days, the Moon will set later each day, becoming visible for more of the night. Within a few days, it will not make it very far above the eastern horizon before nightfall. By the time it reaches full phase, it will be visible for much of the night, rising at around dusk and setting at around dawn.

  • March 6 - Conjunction of Mars and Eris - 17:14 UTC. Mars and 136199 Eris will share the same right ascension, with Mars passing 13°11' to the north of 136199 Eris. Mars will be at mag 1.3 in the constellation Pisces, and 136199 Eris at mag 18.8 in the neighboring constellation of Cetus.

  • March 7 - Mercury at superior solar conjunction - 00:15 UTC. Mercury will pass very close to the Sun in the sky as its orbit carries it around the far side of the Solar System from the Earth. This occurs once in every synodic cycle of the planet (116 days), and marks the end of Mercury's apparition in the morning sky and its transition to become an evening object over the next few weeks. At closest approach, Mercury will appear at a separation of only 1°41' from the Sun, making it totally unobservable for several weeks while it is lost in the Sun's glare. Mercury will also pass apogee – the time when it is most distant from the Earth – at around the same time, since it will lie exactly opposite to the Earth in the Solar System. It will move to a distance of 1.36 AU from the Earth, making it appear small and very distant. If it could be observed, it would measure 4.9 arcsec in diameter, whilst appearing completely illuminated.

  • March 7 - Mercury at greatest brightness - 21:37 UTC. In the southern hemisphere Mercury will be well placed for observation in the evening sky, shining brightly at mag -1.9. Mercury's orbit lies closer to the Sun than the Earth's, meaning that it always appears close to the Sun and is very difficult to observe most of the time. It is observable only for a few days each time it reaches greatest separation from the Sun – moments referred to as greatest elongation.

  • March 8 - NGC 3532 well placed for observation. Across much of the world the wishing well open star cluster (NGC 3532) in Carina will be well placed for observation. It will reach its highest point in the sky at around midnight local time. At a declination of -58°40', it is easiest to see from the southern hemisphere but cannot be seen from latitudes much north of 11°N. At magnitude 3.0, NGC3532 is tricky to make out with the naked eye except from a dark site, but is visible through a pair of binoculars or small telescope.

  • March 10 - 2P/Encke at perihelion. Comet 2P/Encke will make its closest approach to the Sun, at a distance of 0.34 AU.

  • March 10 - 2P/Encke reaches its brightest. Comet 2P/Encke is forecast to reach its brightest, at around mag 2.9. It will lie at a distance of 0.34 AU from the Sun, and at a distance of 0.66 AU from the Earth.

  • March 12 - 73P/Schwassmann-Wachmann reaches its brightest. Comet 73P/Schwassmann-Wachmann is forecast to reach its brightest, at around mag 11.7. It will lie at a distance of 0.98 AU from the Sun, and at a distance of 1.41 AU from the Earth.

  • March 12 - Full Moon - 14:55 UTC. At this time in its monthly cycle of phases, the Moon lies almost directly opposite the Sun in the sky, placing it high above the horizon for much of the night. The sequence of full moons through the year are often assigned names according to the seasons in which they fall. This month's will be the third to fall in winter 2017 – the Lenten Moon. Over the nights following 12 March, the Moon will rise around an hour later each day, becoming prominent later in the night. Within a few days, it will only be visible in the pre-dawn and early-morning sky. By the time it reaches last quarter, a week after full moon, it will rise at around midnight and set at around noon. At the exact moment when the Moon reaches full phase, it will lie at a declination of +04°44' in the constellation Leo, and so will appear high in the sky at all but the most extreme latitudes. It will be visible at all latitudes between 84°N and 75°S. Its distance from the Earth will be 388 000 km (241 083 miles). This full moon was known by early Native American tribes as the Full Worm Moon because this was the time of year when the ground would begin to soften and the earthworms would reappear. This moon has also been known as the Full Crow Moon, the Full Crust Moon, the Full Sap Moon, and the Lenten Moon.

  • March 14 - Conjunction of the Moon and Makemake - 09:48 UTC. The Moon and 136472 Makemake will share the same right ascension, with the Moon passing 27°45' to the south of 136472 Makemake. The Moon will be at mag -12.6 in the constellation Virgo, and 136472 Makemake at mag 17.0 in the neighboring constellation of Coma Berenices. The Moon will be 16 days old.

  • March 14 - Close approach of the Moon and Jupiter - 21:36 UTC. The Moon and Jupiter will make a close approach, passing within 2°19' of each other. The Moon will be at mag -12.5, and Jupiter at mag -2.4, both in the constellation Virgo. The pair will be too widely separated to fit within the field of view of a telescope, but will be visible to the naked eye or through a pair of binoculars.

  • March 15 - Conjunction of the Moon and Haumea - 22:24 UTC. The Moon and 136108 Haumea will share the same right ascension, with the Moon passing 25°28' to the south of 136108 Haumea. The Moon will be at mag -12.4 in the constellation Virgo, and 136108 Haumea at mag 17.3 in the neighboring constellation of Bootes.

  • March 17 - Conjunction of Venus and Mercury - 23:12 UTC. Venus and Mercury will share the same right ascension, with Venus passing 9°32' to the north of Mercury. Venus will be at mag -4.3, and Mercury at mag -1.4, both in the constellation Pisces. The pair will be too widely separated to fit within the field of view of a telescope or pair of binoculars, but will be visible to the naked eye.

  • March 20 - March equinox - 10:21 UTC. The Sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world. This is also the first day of spring (vernal equinox) in the northern hemisphere and the first day of fall (autumnal equinox) in the southern hemisphere. Equinoxes occur twice a year – in March and September – once when the Sun is travelling northwards, and once when it is travelling southwards. The position of the Sun at the moment of the March equinox is used to define the zero point of both right ascension and declination. In practice this is not exactly the case, however, because of a phenomenon called the precession of the equinoxes. Over hundreds of years, the direction of the Earth's spin axis in space changes because it acts like a gyroscope. This means that the location of the equinoxes creep across the sky at a rate of around 50 arcseconds each year. Astronomers quote right ascensions and declinations based on the configuration of the Earth's path around the Sun on January 1, 2000. Even in the years that have passed since the year 2000, the precession of the equinoxes has moved them by several arcminutes.

Video courtesy National Geographic

  • March 20 - Close approach of the Moon and Saturn - 10:54 UTC. The Moon and Saturn will make a close approach, passing within 3°25' of each other. The Moon will be at mag -11.9, and Saturn at mag 0.2, both in the constellation Sagittarius. The pair will be too widely separated to fit within the field of view of a telescope, but will be visible to the naked eye or through a pair of binoculars. The Moon will be 22 days old.

  • March 20 - Moon at Last Quarter - 16:00 UTC. The Moon will be prominent in the dawn sky, rising at around midnight. Over coming days, the Moon will rise later each day, so that it is visible for less time before sunrise and it less far above the eastern horizon before dawn. By the time it reaches new moon, it will rise at around dawn and set at around dusk, making it visible only during the daytime. Over the next few days, the distance between the Moon and the Sun will decrease and it will rise later each day. By the time it disappears into the Sun's glare as it approaches new moon, it will only be visible very shortly before sunrise.

  • March 22 - Conjunction of the Moon and Pluto - 06:17 UTC. The Moon and 134340 Pluto will share the same right ascension, with the Moon passing 2°43' to the north of 134340 Pluto. The Moon will be at mag -11.4, and 134340 Pluto at mag 15.1, both in the constellation Sagittarius. The pair will be too widely separated to fit within the field of view of a telescope but will be visible through a pair of binoculars. The Moon will be 24 days old. 

  • March 23 -  136472 Makemake at opposition - 08:02 UTC.  136472 Makemake will be well placed for observation, in the constellation Coma Berenices. It will be visible for much of the night, reaching its highest point in the sky at around midnight local time.

  • March 25 - Venus at inferior solar conjunction - 10:12 UTC. Venus will pass very close to the Sun in the sky as its orbit carries it between the Sun and Earth. This occurs once in every synodic cycle of the planet (584 days), and marks the end of Venus's apparition in the evening sky and its transition to become a morning object over the next few weeks. At closest approach, Venus will appear at a separation of only 8° from the Sun, making it totally unobservable for several weeks while it is lost in the Sun's glare. Venus will also pass perigee – the time when it is closest to the Earth – at around the same time, since it will lie on exactly the same side of the Sun as the Earth in the Solar System. It will move to within a distance of 0.28 AU from the Earth, making it appear with its largest angular size. If it could be observed, it would measure 59.4 arcsec in diameter, whilst appearing completely unilluminated.

  • March 27 - Conjunction of Mercury and Uranus - 05:57 UTC. Mercury and Uranus will share the same right ascension, with Mercury passing 2°24' to the north of Uranus. Mercury will be at mag -0.8, and Uranus at mag 5.9, both in the constellation Pisces. The pair will be too widely separated to fit within the field of view of a telescope but will be visible through a pair of binoculars.

  • March 27 - Conjunction of the Moon and Venus - 12:42 UTC. The Moon and Venus will share the same right ascension, with the Moon passing 11°19' to the south of Venus. The Moon will be 29 days old. The Moon will be at mag -7.0, and Venus at mag -4.1, both in the constellation Pisces. The pair will be too widely separated to fit within the field of view of a telescope or pair of binoculars but will be visible to the naked eye.

  • March 28 - New Moon - 02:59 UTC. The Moon will pass close to the Sun and become lost in the Sun's glare for a few days. The Moon's orbital motion carries it around the Earth once every four weeks, and as a result its phases cycle from new moon, through first quarter, full moon and last quarter, back to new moon once every 29.5 days. This motion also means that the Moon travels more than 12° across the sky from one night to the next, causing it to rise and set nearly an hour later each day. Click here for more information about the Moon's phases. At new moon, the Earth, Moon and Sun all lie in a roughly straight line, with the Moon in the middle, appearing in front of the Sun's glare. In this configuration, we see almost exactly the opposite half of the Moon to that which is illuminated by the Sun, making it doubly unobservable because the side we see is unilluminated. Over coming days, the Moon will rise and set an hour later each day, becoming visible in the late afternoon and dusk sky as a waxing crescent which sets soon after the Sun. By first quarter, in a week's time, it will be visible until around midnight.

  • March 29 - Conjunction of the Moon and Mercury - 07:17 UTC. The Moon and Mercury will share the same right ascension, with the Moon passing 6°35' to the south of Mercury.  The Moon will be at mag -8.6, and Mercury at mag -0.6, both in the constellation Pisces. The pair will be too widely separated to fit within the field of view of a telescope or pair of binoculars but will be visible to the naked eye.

  • March 29 - Conjunction of the Moon and Eris - 09:34 UTC. The Moon and 136199 Eris will share the same right ascension, with the Moon passing 8°35' to the north of 136199 Eris. The Moon will be at mag -8.7 in the constellation Pisces, and 136199 Eris at mag 18.8 in the neighboring constellation of Cetus.

  • March 30 - Mercury at dichotomy - 05:32 UTC. Mercury will be well placed for observation in the evening sky, shining brightly at mag -0.5. Mercury's orbit lies closer to the Sun than the Earth's, meaning that it always appears close to the Sun and is very difficult to observe most of the time. It is observable only for a few days each time it reaches greatest separation from the Sun – moments referred to as greatest elongation. Mercury's phase varies depending on its position relative to the Earth. When it passes between the Earth and Sun, for example, the side that is turned towards the Earth is entirely unilluminated, like a new moon. Conversely, when it lies opposite to the Earth in its orbit, passing almost behind the Sun, it appears fully illuminated, like a full moon. However, at this time it is also at its most distant from the Earth, so it is actually fainter than at other times. Mercury shows an intermediate half phase – called dichotomy – at roughly the same moment that it appears furthest from the Sun, at greatest elongation. The exact times of the two events may differ by a few hours, only because Mercury's orbit is not quite perfectly aligned with the ecliptic.

  • March 30 - Conjunction of Mercury and Eris - 12:30 UTC. Mercury and 136199 Eris will share the same right ascension, with Mercury passing 15°29' to the north of 136199 Eris. Mercury will be at mag -0.4 in the constellation Pisces, and 136199 Eris at mag 18.8 in the neighboring constellation of Cetus.

  • March 30 - Conjunction of the Moon and Ceres - 20:25 UTC. The Moon and 1 Ceres will share the same right ascension, with the Moon passing 2°14' to the south of 1 Ceres. The Moon will be 2 days old. The Moon will be at mag -10.3, and 1 Ceres at mag 9.0, both in the constellation Aries. The pair will be too widely separated to fit within the field of view of a telescope, but will be visible through a pair of binoculars.

Video courtesy Hubble Space Telescope

Sources: InTheSky by Dominic Ford, NASA

Featured image background by Solar System Scope. Edit: TW

Comments

No comments yet. Why don't you post the first comment?

Post a comment

Your name: *

Your email address: *

Comment text: *

The image that appears on your comment is your Gravatar