While a lot of the eye final week was on space lasers, one thing else caught my eye. Do you bear in mind the Wisconsin pharmacist who destroyed over 500 doses of vital COVID-19 vaccines? According to the Washington Post, this pharmacist additionally believes the Earth is flat. Unfortunately, different individuals do too whilst that has been debunked repeatedly. There was one thing tucked away in the identical article that triggered one of many greatest eye rolls of 2020 for me. Andrea Salcedo wrote, “In another interview with authorities, Sticker said Brandenburg sent her text messages promoting false beliefs he supported, including that the sky was not really the sky but a ‘shield put up by the government to prevent individuals from seeing God,’ court records show.” I by no means envisioned penning this, however let’s focus on why the important thing sky is actual.
When defining one thing, I often like to begin with the dictionary. Merriam-Webster Online dictionary defines the sky as, “the upper atmosphere or expanse of space that constitutes an apparent great vault or arch over the Earth.” The first definition at Dictionary.com says the sky is, “the region of the clouds or the upper air; the upper atmosphere of the Earth.” We lookup on the sky all the time however actually could by no means take into consideration its precise definition.
As an atmospheric sciences professor, I usually ask college students, “How high is the sky?” This query offers me a possibility to clarify the ambiance of the planet and its transition to area. If we function from this angle, the thickness of Earth’s atmosphere varies from about 60 to 6000 miles, relying on the way you body the reply (see dialogue beneath). In the image above, the skinny blue layer is looks like the pores and skin of an onion in comparison with the planet beneath it, which has a diameter of roughly 8000 miles.
Weather, the ozone layer, and lots of different fascinating issues are discovered inside this comparatively skinny layer. According to NASA’s website, the ambiance is damaged into 6 distinct layers (graphic above):
- The troposphere extends from the Earth’s floor to roughly 5 to 9 miles (8 to 14.5 km) excessive. It is the layer of the ambiance most of us will spend our whole lives inside. It additionally incorporates most climate processes and density.
- The stratosphere is the following area, and it stretches 31 miles (50 km) excessive. It incorporates the vital ozone layer that protects us from dangerous ultraviolet (UV) radiation from the solar.
- The mesosphere extends one other 53 miles (85 km) above the stratosphere and is the place many meteors meet their demise.
- The thermosphere can lengthen 372 miles (600 km) above the mesosphere and should function the Aurora “light show.”
- The ionosphere is a layer of ionized particles stretching from the floor to the sting of area. Radio communications are doable due to this layer.
- The exosphere is the layer earlier than the transition to area and extends from the highest of the thermosphere a further 6,200 miles (10,000 km).
My dialogue of the sky has been relatively “Earth atmosphere-centric” given the aforementioned definitions. However, it’s price mentioning that different views are doable. According to q-files.com, their reply to “How high is the sky?” could be framed from the angle of a broader context. The web site factors out, “Yet another answer is the distance of the stars we can see in the night sky.” Many of those objects are measured by way of mild years.
In a world of wacky conspiracy theories, the science assures us that the sky is actual whilst how we outline its higher boundary could range.