Vernal Equinox (long)

[M3Vert]

Orbital Objectivity

The Vernal Equinox is upon us; the first day of the season called spring. Five days ago we were warned, as Julius Caesar was, to, “Beware the Ides of March.” Although that soothsayer’s dire prediction became all too true for Caesar, it need not taint our modern understanding of the Ides. The Roman calendar is defined by the Kalends, the Nones and the Ides. They are quite simply the days of the months; Kalends being the first day of all the months, Nones being the seventh day of March, May, July and October or the fifth day of all the other months, and Ides being the fifteenth of March, May, July and October or the thirteenth day of all the other months. It really has nothing to do with danger except in our fanciful mind’s interpretation of a Shakespearean classic. Unfortunately, the grandeur of Sir William will forever be more attractive than the perceived banality of science and so most of this is lost on most of us. So what is the Equinox anyway? Most would probably say it marks the beginning of spring (in the Northern hemisphere) and even, perhaps, that it is the day when light and darkness are equal due to the sun passing over the equator of the earth. And they would be correct in saying both but the real story is in the details; isn’t it always?

Even though the Vernal Equinox is the exact point when the Earth is half way along the journey from winter to summer in the Northern Hemisphere, our measure of the equality between night and day is skewed by human perception. The difference between sunrise and sunset is not exactly 12 hours on this March 20th, or any other day for that matter. As the sun makes its way to the horizon, the Earth’s atmosphere refracts the rays and we “see” light before the sun breaches. Our perception of the sunrise is a trick of light that allows us to experience it before the sun truly rises so we record it earlier than it actually occurs. That makes the difference between sunrise and sunset 12 hours and 9 minutes instead of exactly half of a 24 hour day. Science got it right but we recorded it incorrectly; that’s probably not the first time human perception failed us and it certainly won’t be the last.

The other fascinating part of the Equinox is the impact it has had on Astronomy. The First Point of Aries, also called the vernal equinox point, is one of the two points on the celestial sphere where the celestial equator intersects the ecliptic. Simply put, it is defined as the position of the sun on the celestial sphere at the time of the vernal equinox – which it was when originally defined. The interesting part is that due to precession, the point gradually moves around the ecliptic so that, in today’s sky, it no longer falls in Aries but somewhere between Pisces and Aquarius – where it will fall squarely around the year 2600.

Let’s take a look at precession for a minute so we all understand exactly what that means. It refers to a change in direction of the axis of a rotating object; in this case the Earth. Of the two types of precession, torque-free and torque-induced, the latter is what refers to our discussion of orbital objects. The axis of the Earth undergoes precession due to its non-spherical shape and the gravitational tidal forces of the Moon and the Sun. Because the Earth has an equatorial bulge, much like that spare tire around your waist, the tidal forces attempt to pull it into the plane of the ecliptic. The result is called lunisolar precession and it slowly moves the Earth (along with other precessionary powers) about 1 degree in 180 years.

So what? I asked my self the very same question, while listening to The Stars Look Down by Rush, and I came up with some very simple answers. There’s much at work around us. There are forces of nature we can only hope to understand that continually influence our reality. The shame of it is that too many of us believe our own perception is reality. We forget there is so much out there that we don’t care to, or even try to understand. For me, and maybe for you, I want to look at life more than just “in the available light”.

Brutus

The Stars Look Down

Lyrics by Neil Pearl

Like the fly on the wheel, who says,

"What a lot of dust we're raising."

Are you under the illusion

That you're part of this scheme?

Seems like a lifetime ago

You could look with pride

On your world of dreams

What is the meaning of this`?

And the stars look down

What are you trying to do?

And the stars look down

Was it something I said

And the stars look down

Like the rat in a maze who says

"Watch me choose my own direction."

Are you under the illusion

The path is winding your way?

Are you surprised by confusion

When it leads you astray?

Have you lived a lifetime today -

Or do you feel like you just got carried away?

What is the meaning of this?

And the stars look down

What are you trying to do?

And the stars look down

Was it something I said?

And the stars look down

Something you'd like me to do?

And the stars look down

[ryyannon]

You're urgently needed in the 'Question and Answer' Thread, M3Vert...

[M3Vert]

On my way . . .