What Does the Night Sky Have to Offer? Finding the Good Stuff…

What Does the Night Sky Have to Offer? Finding the Good Stuff…

Once upon a time… when humanity still hadn’t invented electricity—when oil-lamps and candles were still all-the-rage—people would go to bed shortly after sunset, wake up at sunrise, and then go about their business.  Candles and oil for lamps were expensive items few could afford, and were needed in dark places in the daytime—nighttime was for sleeping. 

Why?  Except for a couple of bonfire festivals celebrating the change of seasons, there was almost nothing else to do in the dark.

 Even as recently as the 1500s, the ability to read was the domain of the wealthy, or those apprenticed to religious orders to become scribes, nuns, and monks.  The latter group were destined to hand-write the religious texts of the day, so they had to be able to read.

The only people that have reliably stayed up all night throughout history were shepherds protecting livestock from nocturnal predators.  Other than cows lowing and sheep bleating, it was a pretty dull occupation.

          The only thing the least bit fascinating was the sky above—the television of its day—with its constant trackable changes.  But every once in a while, it would do something dramatic, and people would pay particular attention.

November 1833

People knew about "falling stars," or as we call them now, meteors.  These are tiny particles shed from passing comets, generally the size of a grain of sand, but occasionally as large as a compact car.  They burn up in our atmosphere in just seconds, leaving a trail of hot plasma (ionized gas) in their wake.

People treated them as clues, telling us the will of invisible gods up in the sky, so we'd know when to sacrifice virgins or whatever weird custom prevailed at the time.  Others saw them as good luck or an opportunity for wishing.

          Most intellectuals felt they were harmless, but the Leonid Meteor Storm of 1833 frightened a lot of people.  The biggest on record, it ranged from 100,000 to a quarter of a million meteors per hour—4,000 per minute—67 per second, for nine straight hours!

          That would have been a sight to see.  Historians at the time reported that it was so bright outside that you could easily read a newspaper, almost like daylight.

Using your Bare Eyes

          Not all meteor showers are like this, of course—few ever gain the official title of "storm."  Some are quite modest, with just a few per hour, and others might give us 16 meteors per minute (1,000/hour), which is great fun to watch.  And the best thing is that they are predictable, happening at the same time each year, each with the potential to be wholly dull or wildly spectacular, and so it's a fun gamble.

Some showers are known for their big objects, that race across the sky, leaving a massive fiery trail behind them.  They may not be quite as big as a Volkswagen Beetle—perhaps a rock just the size of your fist—but the trail sits there in the sky for many seconds, causing us to give them the name Fireballs

It makes you truly appreciate the value of our atmosphere as it protects us from all these incoming rocks moving at 40,000-260,000 kph (25,000-160,000 mph).  Between the years 2000 and 2019, we’ve had 26 “atom-bomb scale” events that our atmosphere tossed aside to protect us.  Most recently, it happened in June 2019 close to Puerto Rico (shown here as seen from orbit).  Measuring 4 meters, or 13 feet in diameter, it was ¼ the power of the Hiroshima atomic bomb of Aug 6th, 1945.

Constellations

          Some constellations are visible in the sky all year.  In the Northern Hemisphere, for example, the Big Dipper and the Little Dipper spin around the star Polaris that never sets.  On the top half of our planet, towards the east, south, or west, you'll find constellations that are only visible at certain times of the year. 

In the Southern Hemisphere it is just the opposite—all-year constellations such as the Southern Cross travel around the southern pole, with transient constellations in the east, west, and north.

The Moon

          This is a great target, too, because the unaided eye can see interesting details.  Add in a pair of binoculars, and the Moon becomes much more interesting.  You can make out individual craters, and study lunar geography (though technically it would be selenography on the Moon).

Due to positioning, there are events called eclipses, where all the shadows between Sun, Earth, and Moon align.  Total Solar eclipses occur approximately once every six years and total lunar eclipses every three years.  Lunar eclipses are visible over a wide geographic area, but solar eclipses require you to be in an exact strip where the shadow will travel.  However, we get partial eclipses much more frequently, at least four per year, and sometimes up to seven events.  The last seven eclipse year was in 1982, and the next one is in 2038.

Using a Telescope

Planets

          Planets are always a fun target.  If you pick Jupiter or Saturn, you can try to see how many of their 79 or 62 moons (respectively) that you spot and identify.  Mars has two moons, too, but they are so tiny that they will be nearly impossible to spot—good luck!  Venus, on the other hand, has no moons, but it does have phases, just like our Moon.

          Taking pictures of planets is covered in our article Astrophotography, [Author's note: insert a link to Astrophotography article in preceding link] describing how you can obtain photos of planets for your collection.  Here's Neptune, assembled from hundreds of individual shots like “image 1” and computer-processed and composited to “image 2”.  Neptune is the furthest planet in our solar system, 2.78 billion miles, or 30 times the distance to the Sun from Earth.

Deep Sky Objects (DSOs)

          There are far fainter things to see.  For example, if you have heard of the constellation Orion (the Hunter), it is relatively easy to spot from January until March in the Northern Hemisphere.

The Horsehead Nebula

The leftmost of the three stars that form his “belt” is called Alnitak.  Just below it is the Orion Nebula.  Hidden inside is a nebula made of dark, unlit stellar gasses that looks like a horse head.  Guess what it is called…

The Takeaway

          We have only scratched the surface, of course.  There are 400 billion stars in just our galaxy.  If you focused a telescope on the smallest, blackest part of the sky at the highest stable magnification, you’d find dozens of entire galaxies where you thought there was nothing at all.  Look here to see just the nearest 400,000 galaxies (not individual stars), which is only 1/250000th of the Universe.

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