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Fourth rock from the sun
As THE cosmos intrigues us with its countless mysteries, space has turned into the most sought-after place for exploration and habitation. Missions, both robotic and human, are being planned to make it possible for people to leave their home planet and travel to other fascinating worlds. Mars is now no longer a planet beyond reach. The Moon, Earth’s satellite, is on the threshold of being walked and settled upon by explorers from the “third rock from the sun.”
But how far are we actually from flying off to other planets and stars? According to the new space vision outlined by the Bush administration, Nasa has been given a long rope to send humans to the Moon and then further on to Mars.
Though robotic exploration costs much less than sending people to other planets and satellites, no robot can substitute the latter, as far as exploring and experiencing an alien terrain is concerned.
Experts feel that only humans will be effective when it comes to unlocking the mysteries of the Red Planet, including the issue of past and present life. Additionally, the technology that is developed for human exploration will benefit humanity for generations to come.
In transit
Scientists feel that using the Moon as a stepping stone to Mars is the most contentious part of the new space programme. They believe that stopping on the Moon en route to Mars would be a waste of resources and funds. The Planetary Society, in the same context, has issued it’s own statement.
According to Louis Friedman, executive director of the society, “Carl Sagan remarked, many years ago, that the Moon could end up a detour, rather than a stepping stone to Mars. How lunar missions would lead to a Mars landing must be closely examined.” The White House, on the other hand, still states that going to the Moon will be an important demonstration of mankind’s ability to actually settle on another planet.
The White House further points out it’s important to fully understand and analyze the technology that is being used before missions are sent out in space. Interestingly, although there is no mention of a “Moon Base,” President Bush, in one of his speeches, did mention an “extended human presence,” on the Moon and “living and working there for extended periods of time.”
While supporters of settling on the Moon say that solar power collectors positioned on the satellite could beam energy back to Earth, others hotly debate the idea. But does Nasa really need this broad canvas and a new vision? Analysts argue that after the Columbia disaster, Nasa needs to gain the confidence of the public in the United States’ space programme.
So how far will such seemingly over-confident statements take us? So far, a robotic mission to the Moon has been planned for 2008 and the first manned mission is supposed to happen between 2015 and 2020. As far as the Red Planet is concerned, a mission is also being planned around 2020. Analysts calculate that if Nasa takes 12 years to go to the Moon, then it will only be after a few years that a spaceship will leave for Mars. Also, financial and technological issues will be considered after each step of the programme. On the drawing boards is the crew exploration vehicle, which will first be used to ferry astronauts to the international space station, but will ultimately carry humans to the final frontier.
Walking on an asteroid
With so many things being said about the upcoming space missions, walking on asteroids and other destinations in space might not be such a preposterous idea after all. Moreover, scientists also feel that asteroids might be laden with rich metal deposits and mining those would be beneficial to Earth’s dwindling deposits. The White House has on many occasions pointed out that, “other potential destinations include, asteroids, the moons of Jupiter and deep space sites suitable for large observatories.” For this purpose, Nasa does not plan to be the only contender. Other countries will also be allowed to join this exploration, including private companies.
Scientists are looking forward to this cooperation, as they feel it will help bring together nations of the world. More like an Earth Space Federation: “We’ll invite other nations to share the challenges of this new era of discovery. The vision I outline today is a journey, not a race and I call on other nations to join us on this journey, in a spirit of cooperation and friendship,” stated President Bush in his January 14 speech at the White House. According to him, the journey to explore space will involve humans and robots first exploring our solar system and then moving to other destinations and planets.
Moon struck?
While missions and spacecraft are being perfected, finding a suitable place on the Moon where humans can set up base is a hot topic among researchers these days. They have chosen a relatively cosy spot for weary space travelers from Earth where they can rest or even take up permanent residence. The place is a crater rim near the lunar North Pole, which is almost always sunlit and not far from the water-ice deposits.
Areas, which receive sunlight permanently, will be suitable for providing solar energy for a Moon base. Sites such as these would have “resort-like” temperatures when compared to other lunar sites, where it is either freezing cold, or unbearably hot. Water-ice deposits on the Moon would prove crucial in not only providing drinking water, but also as rocket fuel by breaking down into hydrogen and oxygen.
According to Ben Bussey of John’s Hopkins University, the ideal spot for a Moon base would be the northern rim of the Peary crater, close to the North Pole. The analysis is based on the 53 images that the Clementine spacecraft provided, after orbiting the Moon in 1994 for 71 days.
The Moon is not like Earth, where extreme tilt causes seasons. Its rotational axis is almost upright and a mere 1.5 per cent away from the main plane of the solar system, extending outward from the center of the Sun. As far as Earth is concerned, there is constant sunlight at the North Pole all summer, while in winter the Arctic is in constant darkness. Theorists believe, that on the Moon, there might be high points where the Sun can always be seen. Due to the fact that the Moon has no atmosphere, temperatures go wild as day turns to night (100C to -180C or 212F to -292F). On the other hand, places where the sun always shines might have temperatures relatively mild (-58F or
-50C). “A region with this relatively benign temperature range represents an attractive site for building hardware designed for long-term use,” Bussey and his colleagues write for the journal Nature.
Though scientists seem to be optimistic, they still view the idea with caution. “With the information available, it is not possible to state definitively that these areas are permanently sunlit because the data correspond to a summer rather than a winter day. But we can be certain that they are the most illuminated regions around the north pole and they are also areas on the Moon most likely to be sunlit, given that there are no constantly illuminated areas in the south polar region,” write Bussey and his colleagues.
But water too is an important factor, so regions of the South Pole have not been ruled out. Presently, the European Space Agency’s SMART-1 spacecraft is orbiting the Moon and further details of lunar topography are awaited. While Nasa is planning its reconnaissance mission to the Moon in 2008, India has its first lunar endeavour planned for 2007. The Indian craft will be equipped with US-made radar instruments to detect locations of water. Bussey assumes that water ice on the Moon may be present at both poles or in some craters.
So how far will this new space vision enable humans to venture forth where no man has gone before? We will have to wait and see. Or will powerful countries turn space into a battleground similar to a Star Wars saga? With the race to get to space first gaining momentum, let’s hope we will be able to beyond our greed for power and actually travel and explore the wonders of the cosmos.
Mars attack
Given the hype about exploring the Red Planet, we at Sci-tech World figured it was about time we gave our readers a crash course in the subject. Here are a few facts and figures that you may or may not have known about Mars:
1. In Greek mythology, Mars, or Ares as he was popularly known, was the Greek god of war. For Romans, Mars was their agriculture god.
2. The first aircraft to visit Mars was Mariner 4 (1965).
3. Mars’ orbit is significantly elliptical. This is why there is a great deal of temperature variation across the planet.
4. Though Mars is much smaller than Earth, its surface area is about the same as the land surface area of Earth.
5. There is clear evidence of erosion on the planet, which shows that at some point during the past, there was some kind of fluid present on the planet. Experts are of the opinion that if they keep looking, they are sure to find water on the Red Planet.
6. Mars has a very thin atmosphere composed of carbon dioxide, nitrogen, argon, oxygen and a very negligible amount of water.
7. A small number of meteorites (the SNC meteorites) are believed to have originated on Mars.
8. Quite a few weak magnetic fields are found to be existing on Mars at the moment. Experts believe these fields are the remnants of an earlier global field that was present on the planet.
9. Mars is a lot like Earth in many ways. Studies reveal that most of the planet’s carbon dioxide was used up to form carbonate rocks. However, unlike Earth, Mars is unable to recycle this carbon dioxide back to the atmosphere and so cannot sustain a significant greenhouse effect. The surface of Mars is, thus, much colder than Earth.
— Sci-tech World Report
The writer
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