Lesson 4                                                                                                          October 12, 2001

 

FOCUS:         How Old Is It?

 

If the age of the universe were equal to one summer day, then the past 100,000 years – which saw the rise of modern humans, the dawn of agriculture, and all of written history – would fit into the flash of a firefly at sunset.

Assignment 1

Match ages from the right-hand side of the table with miscellaneous stuff from the left-hand side;

 

“The ages like 50,000 years would have been absurd to a European in 1700.

Scholars had painstakingly studied the chronology of the Bible to calculate how much time passed since the days of Eden, adding up the ages of Adam and his descendants. In the 1650s Archbishop James Ussher came up with the date that would become the standard for over 200 years: God created the Earth in 4004 B.C. – On October 22, to be precise.”

 

	Place for the Letter		Letter	AGE, Years
Tyrannosaurus Rex			A	13 Billion
The Grand Canyon			B	4 Billion
Saber-toothed cat			C	From 2 Billion to 250 Million
Earth’s oldest rock			D	560 Million
The universe			E	200 Million
The pyramids			F	70 Million
Pottery (ancient vase)			G	100,000
Homo Sapiens			H	12, 000
Complex animal life			J	4,500
Ammonites fossils			I	2,500

 

 

 

	светлячок
	было бы абсурдным 300 лет назад
	ученые изучали библейскую хронологию
	сколько времени прошло со времени библейского рая
	определил дату
	дата, которая стала стандартом
	саблезубый тигр
painstaking – усердный, старательный	fossil [‘fo:sэl] – окаменелость, ископаемое

“Nature doesn’t print birth certificates or hammer a year on its creations as if they were coins. Scientists have learned to tell the age of bones, rocks, planets, and stars by using clocks that tick away in the very atoms that form them.”

	выбить год на
	как если бы это были монеты
	часы, отсчитывающие время в самих атомах

Assignment 2

Study the below articles on aging methods.

1.     Tree rings (Dendro-chronology)

Age of living trees 0-12, 000 years

 

2.     Carbon 14

Age of living remains – wood, bones, shell etc. 0-40, 000 years

Scientists can choose among different kinds of natural clocks depending on the scale of time they work with. For the period reaching back 40,000 years of so, they rely on radioactive carbon.

For example, archaeologists know that one of the oldest parts of Stonehenge, a ditch that encircles the famous stones, was dug with antlers found at the site. By measuring the carbon in those antlers, they have determined that the digging took place 5,000 years ago.

	могут выбирать из различных методов
	определили, что копали 5 000 лет назад
ditch [diч]- ров	antlers -

 

3.     Electron Spin Resonance

Age of crystalline materials – tooth enamel, shell, coral etc. 1,000 – 1 Million years

enamel [inǽmэl]- эмаль

 

4.     Radiometric

10,000 – 4,5 Million years

“Zircons are God’s gift to geochemistry”

Fortunately, nature has created the perfect rock lock for geologists. When magma cools, rugged little crystals known as zircons form. They form in magma with uranium in their lattice. Uranium 235 decays into lead with half-life 704 million years. By counting the number of each type of atom in a sample, one can tell how long it has been decaying – if the sample does not gain or loose atoms.

Ones formed, a zircon shoots out just about any contaminant and can survive for billions of years. Over those billions of years, the trapped uranium steadily decays to lead.

Zircons can survive even after the rock where they originally formed erodes away.

In Western Australia geologists have found a zircon crystal 4.4 billion years old trapped inside a rock that dates back only 3.1 billion years.

	природа создала прекрасные часы для геологов
	уран-235 превращается в свинец
	сформировавшись,
	могут сохраняться в течении миллиардов лет
	за миллиарды лет уран значительно переходит в свинец
rugged [‘rΛgid]-прочный, массивный	lattice [lǽtis]– (кристаллическая) решетка
half-life – период полураспада

 

5.     Red Shift (Hubble constant)

Age of Galaxies, Quasars and the Universe – billions of years

Quasars and galaxies are hurtling away from us as the universe expands. As they speed off, the light they emit lowers in frequency and shifts toward the red end of the spectrum – much as a train whistle drops in pitch as it passes by. This process is known as red shift, and by measuring it – and thus the rate it which the galaxies are flying apart – it is possible to figure how long it has been since they were all contained together in one point of infinite density at the moment of the creation of the cosmos. Today’s estimate for the expansion rate indicates that the universe is 13 billion years old.

	галактики уносятся от нас с расширением Вселенной
	этот процесс известен как Красное смещение
hurtle [hэ:tl] – пролетать, с шумом нестись	pitch [piч] – высота звука

 

6.     Star Alignment

Human Civilization period

Idea of the method is evident – to compare changing star alignment (in the way they can be seen from earth) with certain moments at history, when the alignment is known.

For instance the northern alignment of the Pyramids at Giza matches that of two polar stars visible during the era they were built.

	расположение звезд
	в эпоху, когда они были построены

 

Assignment 3

Match methods from the right-hand side of the table with miscellaneous stuff from the left-hand side;

	Place for the Letter		Letter	Methods
Tyrannosaurus Rex			A	Carbon 14
The Grand Canyon			B	Carbon 14
Saber-toothed cat			C	Electron Spin Resonance, sediment layer
Earth’s Oldest Rock			D	Electron Spin Resonance
The Universe			E	Radiometric
The pyramids			F	Radiometric
Pottery (Ancient Vase)			G	Radiometric, Rock Layers
Homo Sapiens			H	Radiometric, Rock Layers
Complex Animal Life			J	Hubble constant (Galaxies velocity / Distance from Earth)
Ammonites Fossils			I	Star alignment

 

POST-SCRIPTUM

If you are 12 years old, or 50, or 90, that only means that certain network of atoms has come together for that time. Many of the individual atoms that make up that network will stay in your body only a short time before been replaced by new ones. And all of those atoms have been wandering through the air and ground and ocean for billions of years, and before than they were made in stars out of other atoms, which in turn reach back to the dawn of galaxies, to the first second of the universe when all matter came into being.

wander [wonde(r)] – скитаться, блуждать

 

 

 

 

Assignment 4

From the list of sentences you have written out during the lesson, mark with color several that you like most; Try to choose useful ones.

 

 

 

 

 

Assignment 5

Discussion: Use of studying History in School

 

It is quite often to hear that some subjects in School are “useless”.

History of human civilization and eons before are very common examples for such reference. Indeed, they seem to be not really applicable in our regular life.

What do you think?