Earth - "Un-Flattened"

There is a hefty price to pay for, *profound*, scientific illiteracy, as is demonstrated here, by the person who contrived the 'info'-graphic below...

In attempting to 'prove' that the Earth is flat, the creator of this image doesn't seem to know that the Sun's apparent movement across the sky, due to the rotation of a round, roughly, spherical Earth, is from East to West and NOT from North to South. Two people making observations, from two different points along a line of longitude (in this case, early in the morning, separated by a few thousand miles), are not going to see the Sun in the sky in the same position in latitude; in fact--they're within the only one-time zone from each other! They will, however, see it at approximately the same elevation from the horizon--and in the case of the graphic, are, in fact, within the one-time zone from each other!

Here's a simple way to demonstrate that the Earth is a globe--or, at least, that it is NOT a flat, linear field.

Take, a sheet of cardboard or poster board--or, even an 8-1/2" x 11" sheet of paper--outside, when the sun is low in the sky, at, or very near the eastern horizon just after sunrise. I should mention, here: you need to know a person who is well West of you, preferably, on the West Coast, but any place considerably West of you will do. (This person should also be of pleasant demeanor - and not mind being awakened in the middle of the night!)

Now, holding the sheet in your hands, in front of you, level to the ground and facing the sun, imagine the sheet to be the flat Earth, and, imagine that a tiny you are standing on the end of the sheet nearest the Sun (farthest from your body) and, you're, also, a tiny friend on the west coast is standing at the end of the sheet farthest from the Sun - the end closest to your body.

Note that the sheet is evenly illuminated by sunlight when it is level with the ground, and that, both you and your friend are standing in daylight - both of you can see the sun in the sky at the same time and at the same elevation. You have just created a scale model of a "flat" Earth, and the sun's position relative to it.

Okay--now, with one hand holding the end of the sheet farthest from you, take the end of the sheet closest to you and bend it, slowly, downwards, toward the ground, with your other hand until you have formed, roughly, a 90° arc. Note that the sun is now shining only on the segment of the arc farthest from you (our "East Coast", in this demonstration). The segment of the arc curved downwards, away from the Sun - the West Coast, is now in shadow. You have just created a scale model of the "curved" surface of the Earth, and the Sun's position relative to it. 

Which scenario works best in explaining why it is daylight at some points on Earth, while, at the same time, it is dark at other points--the 'flat-Earth' model or the 'curved-Earth' model?

OK - now, if you thought that was tricky - let's test this hypothesis by getting some data from your friend to the west.

Give your friend a call on the phone - apologizing, and explaining that you are, "on an important mission of 'scientific discovery', to prove the non-linear, non-'flat'- field properties of the Earth as an 'oblate spheroid'!".... [yeah, uh-huh - you just go ahead and try that!]

When all the yelling, accusations, and humiliation (on your part), have subsided, ask him, or her, this: "Where is the sun, in the sky, right at this moment?"... 

(After another, hopefully brief, round of biting, acerbic, accusatory statements regarding the level of your sanity), he or she will tell you that, it is dark - the sun has not yet risen - and that you should go back to bed! 

This scenario is, of course, best explained because of the curved surface of the Earth, and your friend's perspective (of both the Earth - and of you), relative to the Sun, and it corresponds exactly to the cardboard curvature demonstration.

You have proven the surface of the Earth to be a curve, rather than a plane. That is an excellent thing!
The demonstration works just as well, at or near sunset, where you will get the opposite results, with your friend out west, this time, in daylight, while you are at dusk.

But, to get back to the price paid: it is in the self-betrayal - in front of the entire, civilized, online world, that -- you don't know what the h*ll you're talking about! 

A little common sense--and a demonstration--go a long way, folks!

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Observing the Crescent Nebula

The dark skies of Pie Town, New Mexico allowed me to have one of (if not the best) visual observing experiences of my life. While my colleague, Muir Evenden and I were installing the Astronomical Telescope for Educational Outreach (ATEO) in the mountains of western New Mexico, we had the chance to do a few nights of visual observing.

One of the staff members at SkyPi Remote Observatories, Michael, was generous enough to invite us to his home not far from the observatory to observe through his 20" Obsession Dobsonian Telescope. The views through this fine instrument complemented by the dark clear skies along with his 2" Nagler eyepieces were simply breathtaking. I could go on in this post about every single object I observed in detail due to how amazing they all looked. However, I wanted to share my experience with observing a new object for the first time... NGC 6888, otherwise known as the "Crescent Nebula".

NGC 6888 - The "Crescent Nebula in Cygnus - T.A. Rector (NRAO/AUI/NSF and NOAO/AURA/NSF).

After Michael showed me the Veil Nebula through his telescope, he asked me if I wanted to look at the Crescent Nebula in the constellation of Cygnus. I have read and seen images regarding this object, however, I have never actually observed it. After Michael slewed the telescope to the object, I climbed the ladder to take a glimpse and I was truly speechless! Michael had an Oxygen III filter (which is a necessity for this object) attached to the eyepiece that allowed me to see the emission nebula in detail very much like the image above. Michael said some of his guest observers will say "it looks like an ear".

The Crescent Nebula is about 5000 light-years away from Earth. It was discovered by Friedrich Wilhelm Herschel in 1792. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 colliding with and energizing the slower-moving wind ejected by the star when it became a red giant around 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward-moving shock wave heats the stellar wind to X-ray-emitting temperatures.

After observing this object, I have added it to the list of deep-sky objects to image through the ATEO when it goes online within the next few weeks. We have an Oxygen III filter in the filter wheel attached to the telescope.

A special thank you to Michael from SkyPi Online Observatories for introducing this fine object to me! It brought back great memories of what it was like looking at deep-sky objects through a telescope for the first time.

Source: Wikipedia - Crescent Nebula

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"Hey Rocky - Watch Me Pull an Asteroid Out of My Hat!"

In Feb of 2012, Earth collided with a 65ft. in diameter asteroid, which exploded over the Russian town of Chelyabinsk. We all know the fortunate outcome there--they were extremely lucky, in that, the sonic boom, created by the disintegrating rock (at a height of 15 miles as it careened through our atmosphere toward the ground at 45,000 miles per hour), caused thousands of injuries, partially demolished buildings and shattered windows. Had the asteroid entered the atmosphere at a steeper angle, the results would have been catastrophic.

This is the trail of the Chelyabinsk asteroid which exploded about 14 miles above the ground
with a force nearly 30 times more powerful than the Hiroshima atomic bomb in 2013.
Credit: Neuromainker via YouTube/Screenshot by Irene Klotz for Discovery News.

And we never saw it coming. This meteor snuck right upon us from the direction of the sun, out of sight in the blinding light of day, as if some celestial magician had pulled it out of a hat--then threw it at us.

But, guess what? There's more to this celestial magic act...  

Let's start here...

This past April, Earth's orbit intersected the orbit of an asteroid debris field--the debris train, left in the wake of an orbiting, cometary, or, asteroidal body. This particular field is several times the Earth's diameter, and we were right in the thick of it for the entire month of April, as well as the end of March and the beginning of June. Earth's atmosphere encounters this field, and others somewhat like it, on occasion, every April, which, due to the pull of gravity produces 'fireballs' (unusually bright) and 'bolides' (exploding) meteors. But, parts of the field have been increasing in density over time.

Astonishingly, we've had 16 near-misses by asteroids, since January of this year, some within just a quarter of the distance to the moon, and one, actually, at an altitude of less than our GPS satellites! Most of these objects were just a few meters across, with the exception of one, which was a few kilometers in diameter!

So, is this kind of thing common? Could we experience another collision, similar to the Chelyabinsk event?

Well, it isn't a matter of, "If". Rather--I'm afraid--it's a matter of "When". And, that's not just an 'alarmist'' opinion, either; here's the deal:

Space--particularly interplanetary space--is not, entirely, empty. At any given time, there is an assortment of asteroidal and cometary debris surrounding the Earth, and in its orbital path around the Sun. Most of this debris is particulate. But, the process of the formation of our solar system, left behind a wide range of sizes of fragmented rock and iron. In our immediate neighborhood, there are asteroids composed of this material ranging in size from bits of dust, to rocks---to boulders---to school buses---even to 5-story apartment buildings! The Chelyabinsk meteorite was the size of the latter. And, there are a few asteroids out there--- the size of small moons!

On an average day, Earth's atmosphere encounters two basketball-sized asteroids. In any two-week period, we get slammed, by one SUV-sized asteroid. Some burn up, entirely in the atmosphere--and, some, make it to the ground.

In the early days after the formation of our solar system, there was much more of this material, which ended up on the surfaces of Earth and the moon and other planets. Here on Earth, the processes of weathering and erosion have erased most of the evidence for those impacts. However, there is plenty of left-over for orbital physics to play with.

Earth--and, ourselves--are moving through space, on our annual revolution around "Sol", our star--our sun (counterclockwise, viewed from the Sun's North Pole), at a speed of 33,000 mph. At the same time, we're rotating on our axis, eastward, at a speed of 1,000 mph.

Here's a very fitting analogy: We're driving down the freeway, blindfolded--with the pedal to the floor; eventually, we're going to crash---unless we can prevent it from happening, altogether, with an early detection/warning and response system.

Become a member of the NASA Center for Near-Earth Object Studies (CNEOS), a program that keeps track of these objects by monitoring and plotting their positions, trajectories, and velocities. You could--literally--save the world.

**The title, some of you may remember, is a take-off on the 60's cartoon style, "Rocky and His Friends" ("Bulwinkle" was, undoubtedly, his closest!).

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