Cosmic Howlers
March 2023
TIRED LIGHT?
…some reaching as fast as 48 million kilometres per hour (44 percent of the speed of light). (Astronomy Now, 2012 May, p9)
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The speed of light is approximately 300,000 kilometres per second, which is 1,080 million kilometres per hour – 48 million kilometres per hour is therefore 4.4% of the speed of light.
The figure of 44% quoted in the article would make the speed of light much less at 132,000 kilometres per second!
ANY ROOM FOR ONE MORE?
…by finding its bright star, Arcturus, which is part of a pattern of stars, or asterism, called the Summer Triangle. (New Scientist, 2022 May 21, p51)
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The Summer Triangle is made up of the the three stars Deneb, Vega and Altair.
Each star is the brightest in their constellation: Deneb is in Cygnus (The Swan), Vega is in Lyra (The Lyre) and Altair is in Aquila (The Eagle). Together they form a distinctive pattern (asterism) easily seen in the light summer night sky.
Arcturus (also called Alpha Boötes) is the brightest star in the constellation of Boötes (The Herdsman) but is not part of the Summer Triangle!
SOME MONSTER!
M87 is a monster, one of the largest galaxies known. It has a spherical shape measuring 240 light years in diameter. (The Telegraph, The Night Sky in May 2019)
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The diameter of M87 is estimated to be 132,000 light-years – somewhat larger than the 240 light-years quoted in the article!
A VERY CLOSE SHAVE INDEED
A NASA spacecraft has officially “touched” the Sun, and got to within about eight miles of its core. (The Week, 2022 January 8, p13)
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The spacecraft in questrion was the Parker Solar Probe which flew to within 3.8 million miles of the Sun’s surface. Of course, no probe could possibly survive a trip inside the Sun itself!
THE OLD METHODS ARE CLEARLY THE BEST
[Olbers’] lifelong concern with comets dates from January 1779, when he used his observations of Bode’s comet to calculate its orbit according to Euclid’s method. (Dictionary of Scientific Biography, Vol X, p197, 1974)
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Euclid was an ancient Greek mathematician who lived around 300BC, so he would not have known how to calculate the orbits of comets!
Olbers would have used a method for the calculation of orbits developed by Leonhard Euler, a contemporary of his. Euler’s method employs a first-order numerical procedure for solving the orbital equations using a given initial value.