We have our fundamental needs. I want to shiver with awe and wonder at the Universe.
Last week I was walking in a relatively dark area around home and found myself looking towards Sagittarius - one of the most beautiful regions of the night sky. On clear dark nights the Northern Hemisphere Summer Milky Way is particularly rich -you're looking towards the center. At the center is a supermassive black hole with about four million solar masses and a diameter about seventeen times that of the Sun.1 There is a lot going on in the region, but it is about 26,000 light years away with a lot of dust preventing imaging it - at least in visible wavelengths. Exotics aside - looking at this area with binoculars or just the naked eye on the right sort of night stirs something in us.
The problem is finding a proper night sky. Sky brightness prevents a third of the world's population from seeing the Milky Way - a number that rises to eighty percent in the US. Living in New Jersey I have to travel for real darkness. I was able to travel to some very dark areas just outside the city and, on moonless nights, being in the mountains would show a sky so rich with stars that finding constellations was an impossible task. The zodiacal light and gegenschein were easy and the Milky Way casts shadows. Finding your way around was difficult - and the only things visible were mountains cutting their blackness into the starry sky.2
Some years ago a fellow traveler forwarded a proposal for rating seeing conditions. It isn't as empirical as some of the scientific measurements of sky brightness and turbulence that you would use for observatory siting, but they're a good way for amateur astronomers to describe the sky:
Class 1: Excellent dark-sky site. The zodiacal light, gegenschein, and zodiacal band are all visible - the zodiacal light to a striking degree, and the zodiacal band spanning the entire sky. Even with direct vision, the galaxy M33 is an obvious naked-eye object. The Scorpius and Sagittarius region of the Milky Way casts obvious diffuse shadows on the ground. To the unaided eye the limiting magnitude is 7.6 to 8.0 (with effort); the presence of Jupiter or Venus in the sky seems to degrade dark adaptation.3 Airglow (a very faint, naturally occurring glow most evident within about 15 degrees of the horizon) is readily apparent. With a 32-centimeter (12½) scope, stars to magnitude 17.5 can be detected with effort, while a 50-cm (20-inch) instrument used with moderate magnification will reach 19th magnitude. If you are observing on a grass-covered field bordered by trees, your telescope, companions, and vehicle are almost totally invisible. This is an observer's Nirvana!
Class 2: Typical truly dark site. Airglow may be weakly apparent along the horizon. M33 is rather easily seen with direct vision. The summer Milky Way is highly structured to the unaided eye, and its brightest parts look like veined marble when viewed with ordinary binoculars. The zodiacal light is still bright enough to cast weak shadows just before dawn and after dusk, and its color can be seen as distinctly yellowish when compared with the blue-white of the Milky Way. Any clouds in the sky are visible only as dark holes or voids in the starry background. You can see your telescope and surroundings only vaguely, except where they project against the sky. Many of the Messier globular clusters are distinct naked-eye objects. The limiting naked-eye magnitude is as faint as 7.1 to 7.5, while a 32-cm telescope reaches to magnitude 16 or 17.
Class 3: Rural sky. Some indication of light pollution is evident along the horizon. Clouds may appear faintly illuminated in the brightest parts of the sky near the horizon but are dark overhead. The Milky Way still appears complex, and globular clusters such as M4, M5, M15, and M22 are all distinct naked-eye objects. M33 is easy to see with averted vision. The zodiacal light is striking in spring and autumn (when it extends 60 degrees above the horizon after dusk and before dawn) and its color is at least weakly indicated. Your telescope is vaguely apparent at a distance of 20 or 30 feet. The naked-eye limiting magnitude is 6.6 to 7.0, and a 32-cm reflector will reach to 16th magnitude.
Class 4: Rural/suburban transition. Fairly obvious light-pollution domes are apparent over population centers in several directions. The zodiacal light is clearly evident but doesn't even extend halfway to the zenith at the beginning or end of twilight. The Milky Way well above the horizon is still impressive but lacks all but the most obvious structure. M33 is a difficult averted-vision object and is detectable only when at an altitude higher than 50 degrees. Clouds in the direction of light-pollution sources are illuminated but only slightly so, and are still dark overhead. You can make out your telescope rather clearly at a distance. The maximum naked-eye limiting magnitude is 6.1 to 6.5, and a 32-cm reflector used with moderate magnification will reveal stars of magnitude 15.5.
Class 5: Suburban sky. Only hints of the zodiacal light are seen on the best spring and autumn nights. The Milky Way is very weak or invisible near the horizon and looks rather washed out overhead. Light sources are evident in most if not all directions. Over most or all of the sky, clouds are quite noticeably brighter than the sky itself. The naked-eye limit is around 5.6 to 6.0, and a 32-cm reflector will reach about magnitude 14.5 to 15.
Class 6: Bright suburban sky. No trace of the zodiacal light can be seen, even on the best nights. Any indications of the Milky Way are apparent only toward the zenith. The sky within 35 degrees of the horizon glows grayish white. Clouds anywhere in the sky appear fairly bright. You have no trouble seeing eyepieces and telescope accessories on an observing table. M33 is impossible to see without binoculars, and M31 is only modestly apparent to the unaided eye. The naked-eye limit is about 5.5, and a 32-cm telescope used at moderate powers will show stars at magnitude 14.0 to 14.5.
Class 7: Suburban/urban transition. The entire sky background has a vague, grayish white hue. Strong light sources are evident in all directions. The Milky Way is totally invisible or nearly so. M44 or M31 may be glimpsed with the unaided eye but are very indistinct. Clouds are brilliantly lit. Even in moderate-size telescopes, the brightest Messier objects are pale ghosts of their true selves. The naked-eye limiting magnitude is 5.0 if you really try, and a 32-cm reflector will barely reach 14th magnitude.
Class 8: City sky. The sky glows whitish gray or orangish, and you can read newspaper headlines without difficulty. M31 and M44 may be barely glimpsed by an experienced observer on good nights, and only the bright Messier objects are detectable with a modest-size telescope. Some of the stars making up the familiar constellation patterns are difficult to see or are absent entirely. The naked eye can pick out stars down to magnitude 4.5 at best, if you know just where to look, and the stellar limit for a 32-cm reflector is little better than magnitude 13.
Class 9: Inner-city sky. The entire sky is brightly lit, even at the zenith. Many stars making up familiar constellation figures are invisible, and dim constellations such as Cancer and Pisces are not seen at all. Aside from perhaps the Pleiades, no Messier objects are visible to the unaided eye. The only celestial objects that really provide pleasing telescopic views are the Moon, the planets, and a few of the brightest star clusters (if you can find them). The naked-eye limiting magnitude is 4.0 or less.
I've probably had a dozen nights of Class 1 (mostly above 3000 meters) and a few hundred of Class 2 - the last Class 2 was in the Arizona mountains a few years ago.4 Sadly Class 7 or worse dominates my local seeing. The aurora is a very rare sight and the Milky Way is impossible . There is a certain quality of life associated with real darkness - like being around frogs and insects in the Summer.
1 The size of a black hole is usually described by its Schwarzschild radius- the radius of a sphere such that, if all the mass of an object were to be compressed within that sphere, the escape velocity from the surface of the sphere would equal the speed of light. It turns out to be proportional to the black hole's mass and for simple non-rotating black holes is 2MG/c2. If the Sun could collapse to a black hole its Schwarzschild radius would be about 3 kilometers. If the Earth could collapse it would be nine millimeters. Very tiny black holes of lessor mass evaporate, but that is another story...
2 There are fun things you can try with your eyes when its very dark. Here's an example - search this blog using 'dark' for a few more
3 Magnitude is a modern adaptation of an ancient measure of a star's brightness. The Greeks thought brighter stars were physically larger and assigned a ranking - very bright first magnitude objects down to dim sixth magnitude. It was eventually realized stars appear as point objects with differing apparent brightnesses. A good enough approximation to the ancient assignments is the fifth root of 100 - about 2.512. A first magnitude object is 2.512 times brighter than a second. Arcturus is 0 and the scale goes negative for very bright objects. The Sun is about -27, Venus sometimes gets in the -4 range and the full moon is about -13. Professional and amateur astronomers both use the modern defintion
4 Amateur astronomers are attracted to dark areas and some buy land to site small private observatories. In addition to low sky brightness and average/seasonal cloud cover, atmospheric turbulence is a big issue. Sometimes otherwise identical properties with a kilometer of each other can vary in price by as much as a factor of five mostly on turbulence issues
I've been traveling and not cooking much for myself - at least not creatively. A recent learning is Indian condiments are great on veggie burgers.