Tag Archives: stars

Totally Eclipsed

The traffic notwithstanding, it couldn’t have gone better. This past Monday, in Seneca, South Carolina, my wife, my son, and one of my daughters witnessed three minutes and thirty seven seconds of totality.

The journey began last summer when I decided, without consulting my wife Kathleen, that we had to make the trip to see the eclipse. We had seen partial eclipses before, but never a total eclipse, and here it was, passing just a day’s drive south of us. In terms of weather, South Carolina wasn’t the best choice. It probably had the highest chance of clouds of any part of the path, not to mention the potential for a hurricane or tropical storm. But in this case, closeness counted, because I only had limited time I could take off from work. After selecting Seneca and finding an available hotel, I sprang the surprise on Kathleen and booked the rooms.

In January, I bought a pack of solar filters–not the glasses, but the cheaper cards that you hold in front of your face. I also constructed a cheap projection viewer the weekend before the eclipse. (See the photo at the top).  This was based on plans found online by one of my colleagues and made use of lenses he purchased. He got two sets for $6 and kindly gave me one set.

The morning of August 21, clouds began to drift over Seneca, but by the time the eclipse began, the sun was in the clear and remained that way the entire time. While the moon’s disk bit into the sun, I monitored it using the projection viewer and took some time to watch the goings on here on Earth. The light became noticeably dimmer by the halfway point. Gaps in the leaves of nearby trees projected images of the eclipse on the asphalt parking lot. Shortly before totality, streetlights and security lights switched on.

We watched through our filters as the last sliver of sunlight shrank and winked out, then lowered them and looked into the inky dark of the moon surrounded by the blaze of the solar corona. Venus shone brightly to the west. Kathleen saw another object, probably Jupiter, to the east, although I missed it. To the northeast, the only part of the horizon we could see, the orange-red of sunrise/sunset appeared although the sun was high in the sky. As the moon continued its crawl across the face of the sun, sparkles winked on and off in the gaps between the lunar mountains. Near the end of totality, a couple of them sparkled ruby red on the trailing edge of the moon.

You try to take in everything in those brief moments, but there is too much. It is the longest/shortest two and a half minutes of your life. And there is something else, something you can feel rather than see, something born of the whole complex of phenomena that make up a total solar eclipse: a sense that this is organic, alive, intimately connected with your own life.  We know the sun is the source of all life on our planet, but for those couple of minutes when it isn’t there in the middle of the day, this knowledge becomes tangible. The whole world changes. The temperature drops. The light diminishes. Animals prepare for the coming of night even though it’s nowhere near nightfall. It is as though the universe is reminding us that we, ultimately, are not in charge.

Being an amateur astronomer, I don’t think people ever really feared that the sun might not return following an eclipse. Eclipses don’t happen that often in any one place, but they happen somewhere on Earth every two or three years, and people have long understood the reason: the passage of the moon in front of the sun. Nothing happens to the sun itself, and the moon never stops in its orbit. So no eclipse ever lasts more than three or so hours, and no total eclipse lasts more than a few minutes. But witnessing a deep eclipse, and especially totality, does bring our dependency upon the sun home in a way nothing else can.

 

Celestial Fireworks

They night sky is a fascinating place, particularly if you live under reasonably dark skies.  If you’re blitzed by light pollution, as are those who live in or near major cities, however, it can seem a pretty barren place, devoid of all but the brightest of stars.  In that case you might almost never look up, because what is there to see?

Sometimes, though, nature puts on a show that cuts through even the worst light pollution.  Such a show is in progress right now.  If you go outside just after sunset and look to the west, you’ll see two bright objects very close together and getting closer each day.

The brightest of the pair is Venus, the most brilliant object in Earth’s sky except for the moon and the sun.  No star and no other planet ever shines as brightly as Venus, so it’s instantly recognizable, even if you don’t know anything about astronomy.  Have a look tonight (or on the next clear night) and you’ll see what I mean.

The other object, roughly to the south (left) of Venus is giant Jupiter.  Aside from Venus itself, no planet is brighter than Jupiter, and no star is as bright.  So it, too, is instantly recognizable.  If it’s brighter than anything except Venus, it’s Jupiter.

JupiterVenus20150624The image above shows the evening sky at about 9:00 PM in Baltimore, Maryland on June 24, 2015, the day I’m writing this.   If you trace a line from Venus through Jupiter you’ll come to Regulus, the brightest star in the constellation of Leo, the lion.  Regulus is bright as stars go; it’s the 21st brightest star in the sky.  The two brightest stars in the sky right now are Arcturus, an orange star high up in the sky, and Vega, to the east and one of the three bright stars in the well-known “summer triangle.”  Finding them and comparing them to Jupiter and Venus can be interesting.

But here’s the really neat part: as the month wears on, Venus and Jupiter will grow closer and closer together, until on June 30th they are only about one-third of a degree apart.  How big is one-third of a degree?  Well, the full moon is roughly half a degree in diameter, so on the last day of June, Venus and Jupiter will be closer together than the full moon is wide.

In case you’re interested, this phenomenon–the closest approach of two celestial objects in the sky–is called appulse.  Another term sometimes used is conjunction, but technically conjunction occurs when two objects are at the same right ascension, which is essentially longitude projected onto the sky.  Venus and Jupiter will reach conjunction on July 1st, but they will be slightly farther apart than on June 30th.

By the by, “closeness” in this context is only how the objects appear in our sky.  In reality, Venus and Jupiter are nowhere near each other in space.  They just happen to line up along about the same line of sight from Earth.  Venus is 59 million miles away, while Jupiter is 561 million miles away.  The current positions of the inner planets and Jupiter are shown below.

SolarSystem2015-06-30

An event of this brilliance doesn’t happen too often, so be sure to get outside and have a look as often as possible between now and the end of the month.  And keep looking after that, as Venus and Jupiter continue their dance, gradually separating again in early July.