See you later February, you’ve been a wonderful month, but now it is time to welcome March. Something we delight in here at Armagh Planetarium is how the months got their names. March is a particularly nerdy one. March got its name after the Roman god of war, Mars. Not only was Mars considered the god of war, he was also thought to be a guardian of agriculture, and an ancestor of the Roman people through his sons Romulus and Remus. While the month of March is the third month in the Gregorian (and even the Julian) calendar, it was seen as the first month of the early Roman calendar, and the beginning of the season for both farming and warfare. In the northern hemisphere, the meteorological beginning of spring occurs on the first day of March. The March equinox on the 20th or 21st marks the astronomical beginning of spring in the northern hemisphere and the beginning of autumn in the southern hemisphere.
An excellent thing to look out for this month is Jupiter, the biggest of the planets in our solar system. On 8th March it will be at opposition, meaning it will be at its closest approach to the Earth and its face will be illuminated by the Sun. Because of this, Jupiter will be brighter than it has been at any other time this year and will be visible all night long. This will be your best opportunity to see Jupiter, so why not break out the telescope, or a decent pair of binoculars and try and catch a glimpse of the gas giant. Using a medium sized telescope should allow you to see some of the details in Jupiter’s cloud bands, and a good pair of binoculars should permit you to see Jupiter’s four largest moons (Io, Europa, Ganymede and Callisto). The moons will appear as tiny dots on either side of the planet.
There will be a New Moon in the sky on 9th March, so no moon light will flood the sky and we will be able to see many of the stars. Have you ever wondered how long a lunar month really is? A lunation or synodic month is the mean (average) time from one new moon to the next. The average length of a lunation is 29.530588 days (or 29 days, 12 hours, 44 minutes, and 3 seconds). However, the length of any one synodic month can vary from 29.26 to 29.80 days due to the effects of the Sun’s gravity on the Moon’s eccentric orbit. In a lunar calendar, each month corresponds to a lunation. Each lunar cycle can be assigned a unique Lunation Number to identify it.
There will be a total solar eclipse this month on the 9th, however unfortunately we can’t get as excited about this one, as we did for the eclipse last year. The reason for this is that we won’t be able to see it. Sad faces all around. The path of totality for this eclipse will only be visible in parts of central Indonesia and the Pacific Ocean. A partial eclipse will be visible in most parts of northern Australia and Southeast Asia. So if you’re lucky enough to be travelling to any of these parts of the world on 9th March, please do look out for the eclipse. We here in Northern Ireland will just have to view any photographs that will be taken on the day.
Don’t forget to check out the stars in the night sky. Take full advantage of the New Moon in the sky and gaze upward at all of the celestial goodness. Here is what we recommend:
Leo the Lion is in the southern sky at around about 11:00pm. Orion and Taurus are starting to move out of the sky, and with Leo being one of the main spring time constellations, signaling the end of the winter night sky. The name Leo is Latin for lion, and to the ancient Greeks, Leo represented the Nemean Lion. The monstrous Nemean lion’s rampage ended when the beast was killed by the hero Hercules as one of his twelve labours. Leo was one of the 48 constellation described in the 2nd century Almagest by Ptolemy and remains one of the 88 constellations that adorn the night sky. The constellation has an iconic shape that is easy to recognise. The lion’s mane and shoulders form an asterism known as “the Sickle,” which to modern observers may resemble a backwards “question mark.”
We can also see Hydra, the largest constellation in the sky at this time, measuring 1303 square degrees. It is also one of the longest at over 100 degrees. Despite its size, Hydra contains only one reasonably bright star, Alphard, designated Alpha Hydrae. It is an orange giant with a magnitude 2.0, 177 light-years from Earth. Its traditional name means “the solitary one”. Beta Hydrae is a blue-white star of magnitude 4.3, 365 light-years from Earth. Gamma Hydrae is a yellow giant star of magnitude 3.0, 132 light years from Earth and if Star Trek is to be believed will by Stardate 3478.2 be the site of a United Federation of Planets starbase near the Neutral Zone with the Romulan Star Empire. The constellation of Hydra is commonly said to represent a water snake or a multi-headed mythological monster which like the Nemean Lion was slain by Hercules.
Spring is here! Spring is here! On 20th March we will have the March Equinox. The equinox will occur at roughly 04:30 UTC (Coordinated Universal Time). The March equinox marks the moment the Sun crosses the celestial equator, the imaginary line in the sky above the Earth’s equator, from south to north. Conventional wisdom suggests that on the equinox everybody on Earth gets to experience a day and night of equal lengths, 12 hours of daylight and 12 hours of night time. In fact, the name equinox is derived from the Latin words aequus, meaning equal and nox, meaning night. In reality though, most places on Earth get to see more daylight than night time on the equinoxes. This is because of two reasons: how sunrise and sunset is defined and atmospheric refraction of sunlight.
There will be a full moon on 23rd March, so the night sky will be flooded with moon light. As always this full moon has a name, in fact it has several. The Native Americans called this the Full Worm Moon, as it symbolised the time when the ground would become softer, and earthworms would begin to appear. Its other names include the Full Sap Moon, because maple sap would begin to flow from the maple trees. It also had the names of the Full Crow Moon and the Lenten Moon, and these names were given to signal the end of winter time.
The 23rd March will also see a penumbral lunar eclipse, however like the solar eclipse earlier on in this month, we won’t be able to see it unless we are visiting eastern Asia, eastern Australia or the west coast of America including Alaska.
(Article by Heather Taylor, Education Support Officer)