Scientists are considering the possibility of sending humans to Mars in the coming decades. Although there have been successful manned missions to the Moon in the 1960s and 1970s, Mars is 150 times further away from Earth than the Moon is. Thus the project of sending humans to Mars would require solving an array of problems the Moon missions did not have to face.
One problem is that a round-trip to Marsand back is likely to take at least two years. The trip to the Moon lasted only a few days, and it was easy to bring enough supplies of food, water, and oxygen; but the cargo capacity of space vehicles is too limited to put on board the food, water, and oxygen required by a crew for a period of two years. Without those essentials, though, a Mars mission is impossible.
A second problem is that astronauts on the Mars mission would be in the zero-gravity environment of space for many months at a time. Spending a long time in the zero-gravity environment has negative effects on the human body, such as decreased muscle mass and lower bone density. Over the course of a two-year mission, the effects would be so severe, they would make it impossible for humans to make the trip without experiencing grave medical problems
Finally, astronauts on a mission to Mars would be exposed to dangerous levels of space radiation, much of which comes in the form of charged particles emitted by the Sun. Earth's magnetic field, which normally protects us from dangerous solar radiation, would not be able to protect a spaceship traveling in interplanetary space. Constructing a shield that would protect the whole spaceship from space radiation is at present impossible because if would add too much weight to the ship.
Word Count: 217
The lecturer explained three different solutions to overcome the problems encountered in Mars mission
First, author mentioned the limitation of space vehicle to carry as much as food and water for a round trip of two years. The lecture thinks that it can be solved by hydroponic, which is a technique of growing plants in water rather than soil. As hydroponics need little space, it can be easily cultivated in a spacecraft. Hydroponic plants inhale carbon dioxide and exhale oxygen which also enables supply of fresh air. Additionally, hydroponic technology can recycle water, thus the problem of scarcity of fresh water can also be solved.
Second, the heath problems including loosing muscle mass and lower bone density due to low gravity can be easily resolved by regular exercise and vitamin supplements.
Third, professor argues that sun radiation are not always harmful. He points out the fact that it is possible to make a small shield or shelter which can easily give protection during the time of sun's harmful radiation. It is also possible to keep certain radar instruments which can alert astronauts while sun radiates dangerous rays.
All in all, professor clearly explained three methods to recover from the dangers of Mars expedition.
| Post date | Users | Rates | Link to Content |
|---|---|---|---|
| 2020-01-20 | f.jafary66@gmail.com | 80 | view |
| 2020-01-18 | naziii | 3 | view |
| 2020-01-07 | 3dra | 3 | view |
| 2019-12-27 | Amirreza97 | 3 | view |
| 2019-12-16 | jeffhjz | 3 | view |
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Transition Words or Phrases used:
also, first, if, second, so, third, thus, while
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 8.0 10.4613686534 76% => OK
Auxiliary verbs: 8.0 5.04856512141 158% => OK
Conjunction : 5.0 7.30242825607 68% => OK
Relative clauses : 7.0 12.0772626932 58% => More relative clauses wanted.
Pronoun: 8.0 22.412803532 36% => OK
Preposition: 24.0 30.3222958057 79% => OK
Nominalization: 5.0 5.01324503311 100% => OK
Performance on vocabulary words:
No of characters: 1060.0 1373.03311258 77% => OK
No of words: 203.0 270.72406181 75% => More content wanted.
Chars per words: 5.22167487685 5.08290768461 103% => OK
Fourth root words length: 3.77462671648 4.04702891845 93% => OK
Word Length SD: 2.66971442068 2.5805825403 103% => OK
Unique words: 136.0 145.348785872 94% => More unique words wanted.
Unique words percentage: 0.669950738916 0.540411800872 124% => OK
syllable_count: 325.8 419.366225166 78% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 3.0 3.25607064018 92% => OK
Article: 3.0 8.23620309051 36% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 0.0 2.5761589404 0% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 10.0 13.0662251656 77% => Need more sentences. Double check the format of sentences, make sure there is a space between two sentences, or have enough periods. And also check the lengths of sentences, maybe they are too long.
Sentence length: 20.0 21.2450331126 94% => OK
Sentence length SD: 44.515165955 49.2860985944 90% => OK
Chars per sentence: 106.0 110.228320801 96% => OK
Words per sentence: 20.3 21.698381199 94% => OK
Discourse Markers: 4.7 7.06452816374 67% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 0.0 4.19205298013 0% => OK
Sentences with positive sentiment : 6.0 4.33554083885 138% => OK
Sentences with negative sentiment : 4.0 4.45695364238 90% => OK
Sentences with neutral sentiment: 0.0 4.27373068433 0% => More facts, knowledge or examples wanted.
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.0633235224178 0.272083759551 23% => The similarity between the topic and the content is low.
Sentence topic coherence: 0.0242564300979 0.0996497079465 24% => Sentence topic similarity is low.
Sentence topic coherence SD: 0.0252967094646 0.0662205650399 38% => Sentences are similar to each other.
Paragraph topic coherence: 0.0443541176035 0.162205337803 27% => Maybe some paragraphs are off the topic.
Paragraph topic coherence SD: 0.0346752216686 0.0443174109184 78% => OK
Essay readability:
automated_readability_index: 13.3 13.3589403974 100% => OK
flesch_reading_ease: 51.18 53.8541721854 95% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 11.1 11.0289183223 101% => OK
coleman_liau_index: 13.0 12.2367328918 106% => OK
dale_chall_readability_score: 9.68 8.42419426049 115% => OK
difficult_words: 65.0 63.6247240618 102% => OK
linsear_write_formula: 12.0 10.7273730684 112% => OK
gunning_fog: 10.0 10.498013245 95% => OK
text_standard: 10.0 11.2008830022 89% => OK
What are above readability scores?
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It is not exactly right on the topic in the view of e-grader. Maybe there is a wrong essay topic.
Rates: 3.33333333333 out of 100
Scores by essay e-grader: 1.0 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.