Cool stuff about the Universe

 kw: book reviews, nonfiction, astronomy, universe, humor, essays

Can you see the difference between the two lower rows of light-colored ovals? We'll mention the dark blue ones in a moment. The three ovals in the bottom row are "white", meaning they have the color value #FFFFFF or (255,255,255). According to Dr. Jan Scudder, author of The Milky Way Smells of Rum and Raspberries … and Other Amazing Cosmic Facts, that very pale yellow, which she calls "light beige", is the average color of the Universe. The color value is #FFF8E7 or (255,248,231). I used PowerPoint to produce the ovals and to set them on backgrounds of white, black, and sky blue. 

This is found in the second chapter of the book, in which color values are discussed briefly, but one fact is reversed: A footnote on page 9 states that #000000 is white and #FFFFFF is black, but the reverse is true. Zero means "no illumination" and FF (or 255) means "full illumination". Otherwise, the usage of color values is correct, as I verified with the top set of ovals, #0D0ACB (13,10,203), called "a particularly pleasing deep blue"; the little bit of red and green slightly desaturate the dark blue so it doesn't overwhelm the eyes. The pure blue color of computer screens is a bit harsh all by itself:

In this image, the oval on the left has color value #0000C8 (0,0,200) and the one on the right is "full-on blue": $0000FF (0,0,255). Some people's eyes are more sensitive to the slight difference between the leftmost oval and the one in the center. By the way, values prefixed with the hash are hexadecimal, or base 16, in which the letters A through F represent quantities from 10 through 15.

The book consists of 34 essays, enlightening, humorous essays. The fifth chapter, from which the book's title is taken, is "The galactic center tastes of raspberries and smells of rum". The "dense" gas clouds near the center of the milky way are still hard vacuum compared to the air we breather, but are 3,000 times as dense as most interstellar gas. That makes these gas clouds capable of blocking much of the damaging UV that breaks apart most molecules, so that deep within them (they are hundreds to thousands of light years across) molecules such as ethyl formate survive. Ethyl formate is an ester that is found in abundance in raspberries. Also found is another ethyl compound, ethyl alcohol (ethanol), the "kick" in rum, vodka and whiskey. The author also points out that, if we were to somehow gather a few cubic parsecs of this gas and concentrate it by a factor of ten billion billion (ten quintillion), it would be a rather toxic brew. It may have hints of raspberry rum, but would also contain cyanide compounds and formaldehyde, for example. So it would really be more like the smell (don't taste!) of a preserved corpse of someone who died of cyanide-spiked rum, with an odd raspberry note.

I was interested in the chapter titled, "There's a pitch-black exoplanet". A distant planet designated WASP-12b is as dark as fresh asphalt; it reflects only 6% of the light that hits it. The dark patches on the Moon reflect about 7%, so you can look in the sky at a full moon to get the idea. By the way, the lighter parts of the moon are more like fresh, dry dirt, and reflect perhaps 15%, making the overall "brightness" of the moon about 12%. If the moon were papered over so it reflected 90% or more, it would be six or seven times as bright as it is. I wish Dr. Scudder had mentioned this. I take issue with a statement in that same chapter: "You'll never get a reflection off a star". In a close double, a pair of co-orbiting stars that are perhaps as close to one another as Mercury is to the Sun (36 million miles, or 58 million km), one of the stars is frequently much brighter than the other, and the dimmer star does indeed reflect a little of the brighter star's light. This has been observed spectroscopically. It stands to reason that some of the dimmer star's light will also reflect off its partner, but this would be extremely hard to detect.

There's an interesting timeline in "Jupiter's magnetic field will short-circuit your spacecraft, but Venus will just melt it." According to this Wikipedia article, Earth's magnetic field ranges from 0.25 to 0.65 gauss (refrigerator magnets have around 50 gauss at their surfaces). The larger unit, the tesla, is 10,000 gauss. The high-dollar superconducting magnet in an MRI machine has a strength of 3 to 10 tesla. That can pull the wristwatch off your wrist (or right through it!), which is why you daren't wear any metal into the MRI room. Electronic conductors moved through a magnetic field produce an electric field; that's how generators work. Move a typical laptop or smart phone around in space near Jupiter, and it will generate thousands to millions of volts, throwing sparks all about. Venus is less spectacular, but just as deadly to almost anything not make of tungsten. Its surface temperature is 450°C (~840°F), and the atmospheric pressure is 100 times that of Earth. In the timeline, starting with Venera 4 in 1967 and ending with Vega 2 in 1985, every spacecraft that landed or attempted to land on Venus had the same experience: crushed and then melted, after times ranging from 20 to 127 minutes. That's 13 spacecraft (all sent by Russia) that gathered a total of somewhat over 880 minutes (14.7 hours) of experience of Venusian weather. It's been a while since anyone tried to send something to the surface of Venus, but the Russians intend to try again in 2029. They hope for a "lifetime" of 3 hours on the surface. Perhaps special electronics made of diamond instead of silicon can be developed. And don't leave any air pockets inside your craft so it doesn't get crushed.

Another quibble, sorry to say: In the chapter "An Exoplanet we thought was made of diamond might be lava instead", the planet 55 Cancri e (the letter "e" indicates 5th body in the system, or 4th body that isn't a star) is "twice as physically large as the Earth, and eight times more massive, which tells us it's substantially more dense…" As stated, this is nonsense. 2×2×2 = 8, so the sentence would only make sense if the last phrase were "exactly as dense". However, here we find that the diameter isn't twice that of Earth, but 1.88, and this number cubed is 6.64; we also find that the mass is indeed 7.99 that of Earth, so now, we're in business. 7.99/6.64 = 1.2. The same article states the density of 55 Cancri e as 6.66. The average density of Earth is 5.51. Now the numbers work together properly. This error shows the danger in over-simplifying science when writing for the public. The early thought that this planet might be made of diamond was based on an erroneous measurement of the diameter. Diamond has a density of 3.5, or less when it is impure. And diamond doesn't compress well, so even under great pressure inside the planet, it's not going to rise to 6. Iron-rich silicate magma/lava also has a density near 3.5, but is much more compressible.

In spite of occasional minor blunders the book is delightful. I like the author's writing style.