The Sky at Night Phần 10 pot

Then, after the 1890s, photographic lunar atlases were pro-duced, and we began to realise that we had a really good working knowledge of the whole of that part of the Moon which we can s

39 Onward to the Moon

the area, and found that Linne no longer existed as a crater, but had been replaced

by a small white spot This caused intense interest had been replaced by a small white spot This caused interest everywhere, and telescopes all over the world were swung back to the Moon

Had there been any real change? The answer, surely, must be “no.” The appearance

of Linne does change strikingly according to the angle of solar illumination I have made many observations myself and I have found that there are occasions when Linne does look like a crater, while at other times it is no more than a white spot The final clue came much later, when spacecraft had been sent passed the Moon, and sent back very detailed images Linne is in fact a small, perfectly normal crater, surrounded by a white nimbus This means that Beer and Madler were wrong, but this is quite understandable because, as noted, they used a small telescope Any major surface changes on the Moon date back at least 2,000 million years, and the main features were formed long before that

There was an argument about the origin of the craters Were they volcanic, or were they produced by meteorites hitting the Moon – a cosmic bombardment? The argument began in the eighteenth century, and was only finally settled in recent years I admit that I was on the wrong side I was convinced that the craters were

of volcanic origin, but it is now quite definite that they are impact structures Photography began to play a major role in lunar work during the latter part of the nineteenth century Then, after the 1890s, photographic lunar atlases were pro-duced, and we began to realise that we had a really good working knowledge of the whole of that part of the Moon which we can see from Earth

The Moon rotates in the same time that it takes to complete one orbit of the Earth There is no mystery about this Tidal forces over the ages have been the cause However, it means that part of the Moon is always turned away from us, and before the Space Age we knew nothing definite about it The edges of the Earth-turned hemi-sphere are so foreshortened that they are difficult to map accurately, and it is not easy

to tell a crater from a ridge When I began observing the Moon, when I was still in my teens, I did my best to map these foreshortened areas Because the Moon’s path round the Earth is not quite circular, there is a slight “wobbling” which means that small parts

of the far side are brought in and out of view This effect is known as libration Altogether we can see 58% at any one time There were all sorts of theories about the permanently averted regions, but we had to wait for the arrival of spacecraft

The idea of sending rocket to the Moon seemed pure science fiction well into the twentieth century Then, however, came the breakthrough In 1957, the Russians sent up the first artificial satellite, Sputnik 1, and ushered in the Space Age Only

4 years later, the astronaut made a flight around the Earth – Yuri Gagarin – whom

I had the honour of meeting on several occasions, but even before that a Soviet spacecraft, Lunik 3, had been right around the Moon and sent back the first pictures

of the far side The Russians had actually sent for my own drawings of the libration areas, so I did pay a part I was a minor member of a very large team of observers During the early 1960s, spacecraft from both Russian and America went passed the Moon and sent back photographs which made all earlier maps obsolete Moreover, spacecrafts were actually landed on the lunar surface, and made one very

156 39 Onward to the Moon

important discovery There had been suggestions that parts of the surface were covered with deep dust drifts, so that any spacecraft landing there would promptly sink out of sight If this theory had been correct, then travel to the Moon would have been impossible, but the fact that automatic vehicles landed safely shoed that this was not the case Men really could go to the Moon

In 1961, President Kennedy of the USA announced plans for sending the first astronaut to the Moon before 1970 At the time I thought that this was being widely optimistic, and I said so! I was wrong The Apollo programme was under way, and

as we all know, the first landing was made in 1969 by Neil Armstrong and Buzz Aldrin in Apollo 11

Do you remember where you were when the first landing was made? I know exactly where I was – in Studio 7 at the BBC Television Centre, carrying out a live commentary Believe me, the atmosphere was tense There was so much that could

go wrong – and if the astronauts had made a faulty landing they would have been doomed There was provision for rescue, so when I heard Neil’s voice; “The Eagle has landed!” I felt a sense of immense relief, shared by viewers all over the world For our programme in July 2009, the 40th anniversary, I was able to broadcast an interview I had made with Neil Armstrong, and I was honoured when Buzz Aldrin also joined me Later astronauts knew what to expect Neil and Buzz did not, and were literally “going where no men had been before.” They were great pioneers All in all, I think that it is fair to say that the Moon turned out to be very much

as expected The gravity is only 1/6th as strong as that of the Earth, and the lunar atmosphere is so thin that to all intense and purposes it can be forgotten Neil and Buzz had no difficulty in walking around the Moon, and they were able to bring samples of Moon rock back for analysis in our laboratories The rocks were purely volcanic, but there is no active vulcanism on the Moon now The dinosaurs could have seen the Moon looking almost the same as it does today – though it is hardly likely that they bothered to look!

Other explanations followed Apollo’s 12, 14, 15, 16 and 17 made successful landing, and our knowledge of the Moon was improved beyond all recognition Equipment was left on the surface, and sent back data long after the astronauts themselves had departed

What next? Well, there is every prospect of establishing a base on the Moon, and this will be of the utmost value to mankind To give just one example, a lunar base would be major centre for medical research There will be a physical laboratory, and of course an astronomical observatory, where conditions of seeing will be perfect all the time Also, the Moon is the first step towards sending a manned rocket to Mars On the other hand, we must recognise that a Martian journey is quite different from a lunar journey, and there are several major problems, which we cannot appreciate One of these is dangerous radiation from the Sun and space Of course, this applies equally to the airless Moon, but it will be possible to build radiation-proof centres there, and a journey to the Moon takes only a day or two as against several months

of Mars However, all this talk of reaching Mars lies well in the future yet It has been claimed that the first trips there will take place within the next few decades, but I admit to being rather sceptical

39 Onward to the Moon

One thing must also be borne in mind If we are to go to the Moon, it must be a programme involving all nations, and not only a few Until recently manned space research was confined to America and Russia, but other nations have now joined in, and both China and Japan have expressed tremendous interest Let us hope we can work together, and that a lunar base will be truly international

That is the situation now, 40 years after Apollo 11 It is difficult to say what will happen during the next 40 years One thing, however, is certain; it all began with Armstrong and Aldrin touching down on the bleak rocks of the lunar Sea of Tranquility, and they will be remembered as long as civilisation lasts

I have lived all through the Space Age, and the Sky at Night programme actually started before Sputnik 1 Also, I can claim to be one of the very few people who have met the first airman, (Orville Wright), the first space man (Yuri Gagarin) and the first men on the Moon (Neil Armstrong and Buzz Aldrin) It is possible that the first man on Mars has already been born, but he will certainly be very young, and

as I am now 86 it is not very likely that I shall meet him But I hope that when the first Martian journey takes place the Sky at Night will still be being broadcast once every month I feel that for me it is a great honour for me to have initiated it

My best wishes to all Sky at Night viewers and to those who have read this book

P Moore, The Sky at Night, DOI 10.1007/978-1-4419-6409-0_40,

© Springer Science+Business Media, LLC 2010

In July 1969, the first men reached the Moon They did go “where no men had been before,” and on a programme four decades later, I talked to Neil Armstrong and Buzz Aldrin Apollo 11 seems long, long ago, but the memory of it will never fade.

It is now four decades since men first landed on the Moon, and therefore a good moment to look back and sum up just what this mission signified I have vivid memories

of it, because as one of NASA’s Moon mappers I had the privilege of knowing all the lunar astronauts, and during the whole Apollo programme I was commenting on BBC Television I did go over to Cape Canaveral for the launch of Apollo 17, last in the series, and believe me, it was a never-to-be-forgotten experience.

Chapter 40

Forty Years on

2008 TC3 trail (Credit: Mohamed Elhassan Abdelatif Mahir (Noub NGO), Dr Muawia H Shaddad (Univ Khartoum), Dr Peter Jenniskens (SETI Institute/NASA Ames))

160 40 Forty Years on

Apollo 11 was particularly important because if it had failed, the whole American space programme would have been thrown into chaos, and there would have been strident calls for its total abolition Moreover, there were still qualms about the stability of the Moon’s surface The once-popular theory of deep dust-drifts had been disproved, thanks to the unmanned landers, but there could well be unsafe areas here and there, and as Neil Armstrong and Buzz Aldrin came down

my main feeling was one of anxiety If for any reason the landing were faulty, there could be no second change – and there was no provision for rescue When Neil’s voice was heard saying “The Eagle has landed,” I think my feeling of relief was shared by the whole world Remember too that the later astronauts had a very good idea of what to expect Neil and Buzz did not

The second moment of crisis came when it was time to take off, blasting away

to re-join Michael Collins in orbit The Eagle’s single ascent engine had to work properly, first time Mercifully, there were no problems, but all in all I feel that it was wise to end the series with No 17 Site for Apollos 18–21 had been chosen, but would probably not have added a great deal to what had been already learned, and sooner or later something would have gone wrong Next time men go there, rescue missions will be available

Some people maintain that reaching the Moon is a waste of time and money, but

by national standards the cost is not exorbitant, and the cost of the wars since the invasion of Iraq would pay for the entire space programme well into the twenty-second century A Lunar Base will be of immense value (for example, consider its value to medical researchers), and if all goes well it will be truly international Space is no longer dominated by America and Russia, and China, Japan and India have already joined in the programme I may be accused of being starry-eyed, but genuinely believe that space research may give us the best hope of uniting the Earth

Forty years ago we did not know what lay ahead, and indeed we still do not But July 1959 marked the real beginning of a new era Neil Armstrong’s “one small step” will be remembered for all time

P Moore, The Sky at Night, DOI 10.1007/978-1-4419-6409-0_41,

© Springer Science+Business Media, LLC 2010

Can the Earth ever be hit by an asteroid? Yes – and on 7 October 2008 we were

Dr Alan Fitzsimmons joined me to talk about it.

On 6 October 2008, Richard Kowalski of the Catalina Sky Survey, working with the 1.5 m telescope at Mount Lemmon, north of Tucson in Arizona, discovered a small asteroid It was catalogued as 2008 TC3, and from its distance and brightness

it was thought to be between 7 and 16 feet in diameter – perhaps 10 feet would be

a good estimate Any body as small as that would have to be very close – an NEA (Near-Earth Asteroid) – and observers of the Spaceguard programme were called

in It soon became clear that instead of swooping past us, as most NEAs do, 2008 TC3 was on a collision course

Interest was immense, and observations came in from professionals and amateurs all over the world Almost 600 photometric measurements from 27 separate localities, and spectra were obtained from the William Herschel Telescope on La Palma, indicating that the asteroid was of type C or M This continued for 19 h – and then,

at 02.46 GMT on 7 October, the end came Asteroid 2008 TC3 entered the Earth’s atmosphere, and broke up

According to US Government sources, satellites were able to follow the course of events The doomed asteroid was first detected at 02.45 GMT at an altitude of 35.5 miles (65.4 km) above the ground, but by then the break-up had started The main impact followed less than a minute later, with position latitude 20.8°N, long 32.2°E,

in Northern Sudan, fortunately an uninhabited area The final explosion had happened

at an altitude of 23 miles (37 km) The explosion was probably about as powerful as from 1 to 2 kilotons of TNT, and caused a brilliant fireball in the sky over the Nubian Desert, though very few people were around to see it A low-resolution image of the explosion was obtained by the Meteosat 8 weather satellite, and the infra-red detector arrays in Kenya recorded a sound wave

Obviously, it was important to collect fragments, and this has started on 8 December Altogether 280 were found, with a total weight of 8.7 pounds (3.9 kg) They are known collectively as Almahata Sitta, which is Arabic means “Station Six.” The asteroid

Chapter 41

Impact!

162 41 Impact!

seems to have been an anomalous ultra-fine grained porous polymict ureilite achondrite, with large carbonaceous grains; the fragile material of this class links it to anomalous dark carbon-rich ureilites

This is the first time that fragments have been found from an object previously tracked in outer space Small though it was, it could have caused damage if it had hit a city centre No, we are not immune!

P Moore, The Sky at Night, DOI 10.1007/978-1-4419-6409-0_42,

© Springer Science+Business Media, LLC 2010

For our hour-long “special” we decided to discuss Life in all its aspects; Where did it start? How did it develop? And most important – can it exist on worlds in the universe? During the programme I was joined by Dr Pete Lawrence, Paul Able,

Dr Allan Chapman, Dr Lewis Dartnell, and Dr Giovanna Tinetti; in America, Chris Lintott talked to Dr Jill Tarter; and Dr Bill Barucki; on film, recordings of

Dr Frank Drake, Dr Paul Davies, Dr John Cockell, and the late Professor Sam Tolansky, Arthur C Clarke and Michael Bentine.

There was, however, another participant I began the programme by showing three objects The first was a stone, totally lifeless The second was a lemon, which

is certainly living, but has no consciousness I then wanted an example of intelligent life, so I introduced my beloved black cat Ptolemy, who, I assure you is very intel-ligent indeed Following the programme, Ptolemy had several letters from viewers who were attracted by his appearance, his behaviour and his friendly purr!

Chapter 42

Life?

Ptolemy, my beloved cat (Patrick Moore)

164 42 Life?

In our programme, we had several guests, but they agreed upon three vital points First, we do not know the secret of what we may call “the spark of life,” i.e why the lemon is alive and the stone is not It would be easy enough for a chemist to construct

an artificial lemon, made up of the same materials as the real one and looking very much the same, but it would be as inert as the stone We cannot create life, though, sadly we can kill it with alarming ease

Second, we do not know how life began Some people believe that the first living molecules built up from what was really a kind of chemical “soup” on the surface

of the young Earth; others that is originated in the fiercely hot thermal vents we now find far below the ocean surface There is also “panspermia theory,” according

to which life on Earth did not originate here at all; but was brought to our world by

a comet or an asteroid

Third, we do not yet have the slightest evidence of any life except on Earth The Moon, the only world close enough to be studied in real detail with our ground-based telescopes, is quite definitely sterile, and our spacecraft searching for traces

of life on less unpromising targets, notably Mars, have had no luck at all – leading some authorities to believe that our part in the universe, at least, is devoid not only

of intelligent life, but also of life of any kind – even microbial

Let us try to speculate about numbers Our Galaxy contains about 100,000 million stars, many of them attended by planets We can see at least 100,000 galaxies, but even this accounts for no more than a very small part of the universe The number of planets must be staggeringly large, and it is reasonable to assume that many of these planets must be Earthlike It follows that there must presumably be intelligent Earthlike life But – wait!

My first guest was Dr Lewis Dartnell, who is well known as an astrobiologist He did not dispute the likelihood of life elsewhere, but intelligent life requires a special set

of circumstances – so special, in fact, that civilisations must be very rare indeed Round every star there must be what is commonly known as an ecosphere or

“Goldilocks zone,” where other things being equal, the temperature is neither too hot nor too cold for the existence of complex life-forms (this really means, between the freezing and the boiling points of water at normal pressure) In the Solar System torrid Venus orbits just inside the Zone, chilly Mars just outside and the Earth comfortably

in the middle If we want to find an extra-solar civilisation, we should therefore try to locate an Earth-sized planet orbiting permanently inside the Goldilocks zone of a Sun-like star The planet must have an adequate supply of water and all the elements we need to produce and sustain advanced life Lewis maintains this combination of factors

is so unlikely that in all probability our civilisation is the only one in the entire Galaxy Time must also be taken into account Low-type life appeared here and surpris-ingly soon after the Earth cooled down sufficiently following its condensation from the solar nebula, but sentient life took much longer, with Man a very late arrival on the scene On some planets the parent star may well have changed its output before advanced life had time to develop, but we must remember that there is no proof that low-type life-forms will evolve into intelligent beings It has happened here, but this

is as much as we can say

Searches are going on apace The recently launched Kepler satellite has been designed specially to detect Earth-sized planets – not by seeing them directly, but