In 1961, John F. Kennedy told Congress: “I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth.”
But on 21 July 1969, at 17:54 UTC, the spacecraft Eagle lifted its metaphorical wings and took off from the Moon (well, the upper ascent stage took off, as shown in the photograph below). There followed a rendezvous with Columbia, a flight back to Earth, and an eventual splashdown on 24 July. Mission accomplished.
Fifty years ago, on 20 July 1969, at 20:17:40 UTC, the spaceship Eagle landed on the Moon. Here is the landing site – below, as it was, and above, as seen by the Lunar Reconnaissance Orbiter Camera (LROC). Clearly visible in the LROC image, and illustrated with inset photographs from 1969, are:
Eagle, the Apollo 11 Lunar Module (obviously only the lower half, or descent stage, remains on the Moon)
The Laser Ranging Retro Reflector (LRRR), which still bounces back laser signals from earth (the inset photograph shows a black dust cover still on the LRRR)
Fifty years ago, on 19 July 1969, the spaceship duo Columbia / Eagle entered orbit around the Moon, roughly 3 days and 4 hours after its launch, as part of the Apollo 11 mission. Eagle (with Neil Armstrong and Buzz Aldrin) went on the land on the moon on 20 July while Columbia (with Michael Collins) continued to orbit the moon. When he announced the space programme, Kennedy had said:
“We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.”
Much can be learned from doing hard things, and an enormous amount was learned from the space programme. Solar car teams also learn a great deal from doing hard things. Fifty years after Columbia and Eagle entered orbit, also after hard effort, the University of Michigan Solar Team’s solar car Electrumarrived in public view (at 17:30 Michigan time). They intend to win too!
Fifty years ago, on 16 July 1969, a Saturn V rocket carrying three men (Neil Armstrong, Buzz Aldrin, and Michael Collins), plus the command module Columbia, and the lunar module Eagle, took off from Florida, en route to the first human landing on the moon (above).
Fifty years later, the Dutch Vattenfall Solar Team launched their 10th solar car, Nuna X (below). Catamaran-style solar cars seem to have reached an optimum: the front of Nuna X looks a lot like Nuna 9 and the rear looks a little like Twente’s Red E and Agoria’s Punch 2 – but only on the left side! The new car weighs just 135 kg (298 lbs), which is probably the lightest ever solar car. I think that Twente, Agoria, and everybody else will have their work cut out trying to outrace this latest car from Delft!
Earthrise, taken aboard Apollo 8 by Bill Anders on 24 December 1968 (NASA photo).
With Christmas coming up, it seems appropriate to post this iconic photograph, taken by Lunar Module Pilot Bill Anders on 24 December 1968, while orbiting the moon in Apollo 8. The team also did a live television broadcast, in which Anders read from Genesis:
“For all the people on Earth the crew of Apollo 8 has a message we would like to send you: In the beginning God created the heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters. And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness.”
Command Module Pilot Jim Lovell continued: “And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day. And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day.”
Commander Frank Borman closed: “And God said, Let the waters under the heavens be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good. And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas, and God bless all of you – all of you on the good Earth.”
Shakespeare writes “the moon’s an arrant thief, and her pale fire she snatches from the sun” (Timon of Athens, Act 4, Scene 3). He is, of course correct. The moon merely reflects sunlight, and produces no light of its own. One way of telling this is that moonlight actually displays the same telltale absorption spectrum as sunlight:
Our eyes tend to perceive moonlight as “blueish” or “silvery,” but that is because of the way our eyes work at low light levels. Long-exposure photographs under moonlight, like this one, look much like daytime shots:
Anaxagoras (499–428 BC) seems to have been the first to discover that the moon shines only by reflected light:
Anaxagoras also explained that solar eclipses occur when the moon moves between the earth and the sun. Total solar eclipses are dark precisely because the moon produces no light of its own:
In recent times, there has been a degree of interest – particularly within the USA – in so-called “blood moons” (as in the above book). Although this phrase is intended to recall Biblical texts such as Joel 3:21 (“The sun shall be turned to darkness, and the moon to blood, before the great and awesome day of the Lord comes”), it actually refers to ordinary lunar eclipses. Lunar eclipses are great to watch (see photo below), but are actually not particularly uncommon – see this list.
Much has been made of the “coincidence” of lunar eclipses occurring on major Jewish holidays. However, the geometry of lunar eclipses (see below) requires the moon to be on the opposite side of the earth from the sun, which means that lunar eclipses only occur on full moons. Furthermore, the Jewish calendar is a lunar one, so that several major holidays – such as Passover (15th of Nisan), Purim (in Jerusalem, 15th of Adar), and Sukkot (15th of Tishrei) – always occur on full moons. Lunar eclipses have therefore occurred on major Jewish holidays many times over the past two millennia.
Basically, the whole theory makes about as much sense as the panic of 2012. But, of course, that’s no reason not to watch the next lunar eclipse, on 8 October:
“For do but consider what an excellent thing sleep is: it is so inestimable a jewel, that, if a tyrant would give his crown for an hour’s slumber, it cannot be bought … sleep is that golden chain that ties health and our bodies together. Who complains of want, of wounds, of cares, of great men’s oppressions, of captivity, whilst he sleepeth? Beggars in their beds take as much pleasure as kings. Can we therefore surfeit on this delicate ambrosia? Can we drink too much of that, whereof to taste too little tumbles us into a churchyard; and to use it but indifferently throws us into Bedlam? No, no. Look upon Endymion, the Moon’s minion, who slept threescore and fifteen years, and was not a hair the worse for it. Can lying abed till noon then, being not the threescore and fifteen thousandth part of his nap, be hurtful?”
Scientific Gems 
