The Night Sky This Month: January 2015

Quadrantids Meteor Shower

Moon Phases

Here’s a convenient new tool which quickly shows the Moon phases for your time and location. Give it a click and see what Selene will be up to in your area.

Quadrantids Meteor Shower

The Quadrantids is viewable from the 1st to the 6th; although it peaks on the night of the 3rd-4th, radiating from a point in the constellation Bootes, close to the tail of the nearby Big Dipper. This meteor shower can manage 50-100 meteors per hour, so it can be quite spectacular, but the Full Moon is going to be bright around this time so I suggest looking in the direction of Polaris (the North Star) and using a magazine or star chart to block the Moon out of your vision so you can see the fainter meteors. In Britain it peaks on the 4th at 02:00 GMT, but folks in the United States might miss the peak at 8 p.m.CT. However, the peak time is not always accurate and can miss by as much as a third of a day, so keep an eye out!

Comet Lovejoy

Originating from the Oort cloud, Comet Lovejoy is now naked-eye visible in the Southern sky, near the horizon, below Orion. It’s not much more than a smudge right at this moment, but with a telescope, you should be able to see the tail (or tails, both dust and ion) and it will likely reach mag 4 during the month. Binoculars would certainly help, but a telescope would be very revealing in the colder, dense, still air of winter. Just remember to take the telescope out early to let it cool down before you use it. It will be at closest approach to Earth on the 7th.

Planet Watch

In January, the planets Mercury, Venus, Mars, Jupiter and Saturn will all be visible in the celestial heavens, given a clear night sky.

Venus

The Evening Star (the planet Venus) is visible about 3 finger-widths (5 degrees) above the horizon on the first day of the year as evening begins, but should be about 12 degrees by the end of the month. It will, of course be stunningly bright at a magnitude of -3.9. (explanation of magnitude below).

Mercury, Mars

Mercury will be 19 degrees away from the Sun on the 14th, so if you’re looking to catch a glimpse, it’ll have to be pre-dawn before morning glow overwhelms it, or post-sunset, as the glow fades. It’s not the most elusive planet, but it does have the shortest window for observations since it is always so close to the Sun. In this case just 19 degrees of separation. You should take the opportunity to go and have a look. Mars can also be seen for a few short hours after Mercury sets, and on the 21st January there will be a great opportunity to view a crescent Moon in the south western sky, with Mercury, Venus and Mars all very close nearby.

Saturn

Early in the month, Saturn will be visible in the south east sky two hours before dawn near the constellations of Libra and Scorpius, but by the end of the month the ringed planet can be viewed four hours predawn.

Jupiter In Leo Jupiter

If you can find the constellation of Leo, Jupiter will be located to the right of its Sickle and obvious at mag -2.5. The four Galilean Moons (three of which are even larger than Earth’s Moon) are close to edge-on to us right now, and are playing a game of hide and seek as they zip around our largest neighbour. They have periods of less than two (Earth) days to 17 days, so sometimes they hide behind Jupiter and sometimes they are widely separated. Look for their shadows traveling across Jupiter’s face.

And since Jupiter rotates in just 10 hours or so you can watch all the geometry of the various permanent storms scrolling by (like the Great Red Spot, etc.) along with the varying bands of colour. It would take less than 10 hours to see the entire planet if you wanted to spend the whole night outside… This is because Jupiter is the fastest spinning planet in our whole solar system and doesn’t mind showing off for observers.

What Is Magnitude?

The ancients classified stars according to their apparent size (the meaning of the word “magnitude” is size). They thought their appearance was related to their physical dimensions, rather than their distance and luminosity (brightness). We know better today, of course, They used a system where Magnitude (mag) 1 was the biggest star, and mag 6 was the smallest that the eye could see. With the invention of telescopes many more objects were visible and we can see to the 32nd magnitude with the Hubble Space Telescope.

Over the years we have modified the system to include all visible objects, some of which are brighter than stars, such as Mercury, Venus, Jupiter, The International Space Station (ISS), the Moon, and even the Sun. These are measured in negative orders of magnitude with the Sun (brightest) at mag -27, our Moon at -13, ISS -6, Venus -5, Jupiter -3, Mercury -2, with Saturn and Vega both sitting on the mag 0 mark.

Conclusion

So that’s what’s up for January. Make some cocoa, get a warm hat and gloves, and go take a look at what the Universe wants to show you.