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» Science. Answers from Reality The Five Frontiers of Space by Edward C. Stone

Science. Answers from Reality The Five Frontiers of Space by Edward C. Stone

Science. Answers  from Reality The Five Frontiers of Space by Edward C. Stone

NASA was formed at the dawn of the Space Age as part of the U.S. investment to create a space-faring capability. Today the United States is indeed a space-faring nation, and it is hard to imagine a future in which it does not remain so. Even if there was no longer a NASA, we would continue to develop and deploy more advanced global positioning, communications, weather, reconnaissance, and systems in space.

Given that the United States is and will be a space-faring nation, what is the role of NASA in space today? Although the Space Age began 46 years ago, it is still the newest realm of human activity. There remains much to learn. A primary role for NASA is to expand the frontiers of this new realm in order to foster increasing activity and broader involvement.

Expanding the frontiers of space also serves the national interest by providing opportunities for international partnerships.

There are five frontiers to this new realm of human activity:

1. The physical frontier - going where robotic systems or humans have not been.

2. The knowledge frontier - discovering and understanding natural phenomena.

3. The engineering / technology frontier - developing the innovative engineering and technology required to expand the other frontiers.

4. The human frontier - addressing the physiological, psychological, and other aspects of effective human activity in space.

5. The applications frontier - developing and demonstrating new uses of space.

These frontiers are immense, so choices must be made. Among the criteria for such choices is the extent to which a program or project significantly expands one or more of these frontiers, thereby contributing to the achievement of a long-term goal.

The actual rate of learning or pushing the frontiers is another important measure of the value of individual programs. This is an important criterion for choosing a program. It is also important in deciding to discontinue an activity when the important questions have been answered and the rate of learning has become only incremental or is no longer commensurate with the cost and risk.

In general, space science has long-range goals and roadmaps that are periodically revisited in the light of new knowledge, new capabilities, expected rate of learning, and estimated cost and risk. It also has processes for identifying the best ideas for addressing those goals. Therefore the following focuses on human space-flight.

The human exploration of Mars would clearly expand the physical frontier for human space-flight and could serve as a long-range goal in determining the value of specific investments in the human space-flight program. With proper planning and preparation, the human exploration of Mars would also expand the science frontier. This should be an international goal with a general time frame but not a commitment to a specific date. Sending humans to Mars would require significantly expanding the engineering / technology and the human frontiers while continuing the scientific exploration of Mars with precursor robotic missions. In the near term this suggests that the human frontier should be a high priority for the International Space Station. The capabilities and use of the International Space Station should be optimized to achieve timely and significant progress in understanding the most important factors affecting human effectiveness and safety during long exposures in space. There will also be opportunities for the International Space Station to contribute to the science and applications frontiers.

One of the challenges for human space-flight is choosing programs that will significantly increase the rate of learning associated with expanding the frontiers critical to human spaceflight so that it is commensurate with the investment and the risk. An effective way to increase the rate of learning is to proceed with a series of smaller steps rather than with the occasional, much larger step represented by a single system designed to address many different and often competing objectives. Each step should focus on an aspect of the engineering and technology or human frontier that is crucial to making a human mission to Mars feasible, affordable, and safe. The exact steps will evolve as we learn, but the overall direction will be guided by the long-term goal of the human exploration of Mars. Expanding the frontiers means learning by going new places and trying new things. Doing what has not been done before will entail risk, but that will be acceptable if we are learning what is critical to expanding the frontiers, rather than only incrementally improving what we already know and do. That does not mean, however, that institutionally driven risks are acceptable.

Addressing challenging engineering / technology issues on reasonable time scales (e.g. 5 years) will motivate students and attract the talented workforce needed to tackle hard problems. This is important because there are now many more challenging opportunities in engineering and science than there were at the beginning of the Space Age. As a result, there is much more competition for the brightest and best, and the human space-flight program must offer a higher rate of learning to attract a new generation of technical staff.

Experience with the space science program also suggests that if the human space-flight program was structured to produce more learning, additional funding would follow because the value to the long-range goal of human presence on Mars would be apparent and the progress visible. The challenge for the human space-flight program in the next two decades is to take the steps on the frontiers of space that will make human exploration of Mars not just a dream but inevitable.

(in: Issues and Opportunities Regarding the U.S. Space Program -

A Summary Report of The Workshop on National Space Policy - March, 2004)


Reading comprehension and comments

Can you integrate the contextual valence and meanings of the term 'frontier', as employed in this text, within an ampler cultural circumscribing of the concept? Do you consider it a matter of linguistic coincidence that it occurs here? What do you know about 'the spirit of the Frontier', and its role in shaping the becoming of America?

What do you know about 'the race for the Moon' in the sixties?

What do you know about the present-day exploration of Mars?

Vocabulary study and practice

1. Look up the meaning of any unknown word or phrase in a dictionary.

2. Afterwards, try and find their synonyms and/or opposites among the words and phrases that you had already known.

Grammar Module

The numeral (Numeralul)

Numeralul este, de obicei, definit ca "partea de vorbire care denumeste numarul sau ordinea numerica'; dar din punct de vedere gramatical el nu poate fi socotit parte de vorbire, deoarece, de fapt, indeplineste functiile uneia din urmatoarele parti de vorbire:

a) substantiv: Ten divided by two is five. (Zece impartit la doi face cinci.)

b) adjectiv: The third witness did not want to speak. Cel de-al treilea martor nu voia sa vorbeasca.)

c) pronume: The third did not want to speak. (Cel de-al treilea nu voia sa vorbeasca.)

1. The Cardinal Numeral (Numeralul cardinal

0 zero

1 one

2 two= [tu:];

3 three

4 four= [fo:r];

5 five= [faiv];

6 six= [siks];

7 seven

8 eight= [eit];

9 nine= [nain];

10 ten= [ten];

11 eleven= [i'levn];

12 twelve= [twelv];

13 thirteen

14 fourteen= [fo:'ti:n];

15 fifteen= [fif'ti:n];

16 sixteen= [siks'ti:n];

17 seventeen

18 eighteen= [ei'ti:n];

19 nineteen= [nain'ti:n];

20 twenty= [twenti];

30 thirty

40 forty= [fo:ti];

50 fifty= ['fifti];

60 sixty= ['si:ksti];

70 seventy= ['sevnti];

80 eighty= ['eiti];

90 ninety= ['nainti];

100 a (one) hundred

1000 a (one) thousand

101 - one hundred and one;

163 - one hundred and sixty-three;

1004 - one thousand and four;

2057 - two thousand and fifty-seven;

4258 - four thousand two hundred and fifty-eight;

- se foloseste cratima intre numeralul zecilor si cel al unitatilor
e.g. 21 twenty-one; 99 ninety-nine
- se pune virgula dupa fiecare grup care indica miile
e.g. 1,222,351

- mentionarea conjunctiei and este obligatorie inaintea grupului zecilor si unitatea finala
e.g. 2,532 - two thousand five hundred and thirty-two

NOTE: Hundred, thousand, dozen (duzina) sunt invariabile: e.g. two thousand dollars. Utilizate ca substantive ele primesc "-s" la plural: e.g. hundreds of men (sute de barbate); thousands of soldiers (sute de soldati).

The cardinal numeral is used to express a number, a date, time of the clock, etc.

When we refer to years, we read: e.g. 1985 - nineteen eighty five.

  • Shorter numerals are generally expressed in letters:

Twelve of the crew managed to escape.

Longer numerals, in figures:

This Greek thinker lived 2,500 years ago.

2. The Ordinal Numeral



= primul
= al doilea
= al treilea

The flat is on the sixth floor.

The hero dies in the fourth act.

Pentru a forma un numeral ordinal (numeralele ordinale pun obiectele in ordine), adaugati terminatia "-th" la numeralul cardinal.

seven= seventh= al 7-lea;

thirteen= thirteenth= al 13-lea;

hundred= hundredth= al 100-lea;

thousand= thousandth= al 1000-lea

Atunci cand un numeral cardinal se termina in -y, acesta se schimba in ie inainte de a se adauga "-th".

twenty= twentieth= al 20-lea;

sixty= sixtieth= al 60-lea;


1st= first= primul;

2nd= second= al 2-lea;

3rd= third= al 3-lea;

= fifth= al 5-lea;

= ninth= al 9-lea;

= twelfth= al 12-lea;

De la 21-lea pana la al 99-lea cifra unitatilor este ordinala:

22nd= twenty-second

33rd= thirty-third

58th= fifty-eighth

66th= sixty-sixth etc;

3. The Fractional Numeral (Numeralul fractionar)

= a (one) half

3/5 = three fifths

¼ = a (one) fourth

7 5/6 = seven and five sixths

2/3 = two thirds

Fractiile zecimale (decimal fractions):

35.89 = thirty-five point eight nine

0.09 = (nought) point nought three

4. The Multiplicative Numeral (Numeralul multiplicativ)

1x = single, once (o data)

2x = double/twofold, twice (de doua ori)

3x = triple (treble)/threefold, three times (de trei ori)

4x = fourfold, four times (de patru ori)

10x = tenfold, ten times

100x = a hundredfold, a hundred times

I've been here only once or twice.

We can give a fourfold classification of these materials.


1. Write in letters the following numerals.

Write the following fractions.

3. Write the following dates.

21 June 1994 (the twenty-first of June, nineteen ninty-four)

2 April 1903 (the second of April, nineteen O[ou] three)

5 August 1800 (the fifth of August, eighteen hundred)

3 December 1860 -

30 May 1701 -

23 July 1900 -

4. Read the following phone numbers.

118605 (double one eight six O[ou] five)

255799 (two five five seven double nine)

5. Read the following times of the clock.

3: 25 (It is twenty-five [minutes] past three / three twenty-five)

6:45 (It is a quarter to seven / six forty-five)

6. Translate into English.
1) Ziua mea de nastere este pe data de 22 mai.
2) Am ajuns in Bucuresti pe data de 14 iunie.
3) John este al patrulea elev din clasa.
4) 4 Iulie este ziua nationala a Americii.
5) Primul autobuz din parcare este al nostru.
6) Sunt 14 elevi in aceasta clasa.

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