Aug 01

What’s Up in the Sky

What’s Up in the Sky – August, 2014

King and Queen at Dawn

August’s best observing is usually the Perseid meteors.  This year, though, the bright Moon will drown out all but the brightest streaks so I recommend a different pre-dawn party this month.

Starting on the morning of August 15th,  pay attention to the two brightest objects above the eastern horizon.  That would be Venus and Jupiter.  Now watch at the same time each morning and you will notice the separation between the two decrease each day until the 18th when they will appear to be less than one half degree apart, a distance roughly equal to the apparent diameter of a full Moon or about half a pinky finger held at arm’s length.  That’s really close for planets!  Five days later the separation will have increased and the two will be joined by a thin crescent Moon making a lovely trio in the pre-dawn sky.

Sunrise is a little before 7 a.m. this time of year so the best time to observe this pairing is between 6 and 6:30 a.m.  The later you look, the higher in the sky they will be but the sky will also become brighter so you will need to find a balance.  Use binoculars if it is too bright out.

Regular readers will know that this is one of my favorite types of observation because you get to witness the motion of objects in space.  All the planets move against the background stars from night to night, but it is difficult to notice unless they happen to appear close to another object such as a star or, as in this case, another planet.  And this time the separation changes a lot each day and is therefore easily noticeable.

Back to the Perseids.  Since the Moon will be bright on the night of August 12, rather than trying to see as many meteors as possible, why not try to see a few really cool bright ones that streak across the entire sky from horizon to horizon.  These are called “earthgrazers” and can last for up to a minute as opposed to regular meteors that streak across in a second or two.  Earthgrazers are meteor that skim through the earth’s atmosphere rather than plunge directly into it.  And early in the evening of a meteor shower is the best time to observe them.

So whether you’re a morning or late night person, there’s good stuff to see this month up in the sky.

This month in history:
August 01: Production of Saturn V rocket ends – 1968
August 06: Mars Science Laboratory rover lands on Mars – 2012
August 12: Echo 1 satellite launched – 1960
August 18: Helium discovered in the Sun – 1868
August 25: Voyager 2 flies past Neptune – 1989
August 28: Galileo spacecraft flies past asteroid Ida – 1993