When commentators call the flight of the Orion space capsule 'the next giant leap' for NASA, it harkens back to Neil Armstrong's famous 'one small step' on the moon 45 years ago. In reality, the Orion flight is a very small step back into deep space.
Orion even looks like the Apollo Command module that went to the moon, with the same conical shape that has proven to be best for high-speed entry into the Earth's atmosphere. But that is where the similarity ends.
Orion can carry seven astronauts instead of three, and, of course, has far superior electronics than the computers from the '60s, which were less powerful than an iPhone.
NASA needs Orion as a replacement for the space shuttles that were Two of those seats were filled by Canadians retired in 2011. Since then, the Americans have been in the somewhat embarrassing situation of paying the Russians $70 million per seat for rides up to the International Space Station on their Soyuz rockets. Chris HadfieldThirsk.
With tensions mounting between the U.S. and Russia over Ukraine and Crimea, the Americans have been anxious to get back into the business of launching their own rockets from their own space ports.
The job of getting up to the Space Station and back has been handed over to the private sector, with contracts awarded to companies such as SpaceX and its Dragon Capsules, which have already flown unmanned cargo missions to the station. They will take over where space shuttles left off, carrying people and cargo up to the station at relatively low cost.
Orion is designed to go much farther than that, possibly all the way to Mars.
That's why this four-and-a-half hour flight to an altitude of 5,000 km is such a short hop. Basically, the mission is just to see if the capsule can fly in space, and, more importantly, survive re-entry. Like anything that you throw into the air, the higher it flies, the faster it falls back.
When space shuttles returned to Earth, they were coming down from 400 km, so they hit the atmosphere at 30,000 kilometres per hour (18,000 mph), which is incredibly fast.
Orion will be coming from deep space and travelling more than 2,000 km/hr faster than that, which means it faces higher temperatures from air resistance that can reach 2,700 degrees Celsius (5,000 Fahrenheit).
That re-entry will also be a much rougher ride for astronauts than they experienced in space shuttles.
The shuttles had wings, so they glided to a smooth landing on a runway. Orion relies on a sequence of 11 parachutes, which will provide a series of jolts to the astronauts as the capsule is hauled back to slower and slower speeds on its way down.
The descent ends with a splashdown in the ocean, followed by nauseating rocking and rolling from whatever sea conditions are at the landing site. The capsule can be rigged with air bags for a ground landing, but they won't be used on early test flights. Either way, it's a rocky ride back to Earth, especially for those who have been on very long missions to an asteroid or Mars.
Even the rocket that carried Orion to space this morning, the Delta 4 Heavy, is a stand-in. The job will ultimately go to the space launch system, or SLS, which will be the largest rocket built since the moon missions.
Still under construction, this rocket is basically made out of space shuttle parts without the winged orbiter. A large central tank, with space shuttle engines on the bottom and two strap-on solid boosters, will give it a lift capacity of 70 tons, large enough to hurl a large spacecraft all the way to Mars.
But while these systems were proven over the 30-year history of of the space shuttles, they were also responsible for two catastrophic accidents. A faulty O-ring in a solid booster led to the destruction of Challenger in 1986; and foam shedding from the large fuel tank brought down Columbia in 2003.
Those systems also turned out to be incredibly expensive. During their final years, each launch of a space shuttle was costing more than $1 billion.
Now, those same contractors are building the new rocket with the same technology. Is NASA heading down another road where huge amounts of money will be needed just to get off the ground?
Elon Musk, head of SpaceX, says he can fly his own heavy-lift rocket at one-third the cost.
When it is completed, NASA's SLS rocket will have to be be tested, which will involve more unmanned flights before astronauts can even take a short ride, somewhere around 2021, with a trip to Mars by 2030.
NASA then plans to use the new system to send humans to an asteroid, which critics say is a waste of money because robots have been doing a pretty good job of visiting small objects at much less cost. In fact, Japan just launched Hyabusa 2 to gather a sample from an asteroid and return it to Earth; and we recently saw the spectacular landing on a comet by the European Rosetta mission.
Why go to all the risk and expense of sending humans to an asteroid, when robots have already done it? Perhaps they should press on directly to Mars, but at what expense? Currently, there are no funds in place to support a Mars mission.
So, while the Orion capsule flexes its wings, it is barely out of the nest. There is still a lot of flying to do and a lot of hard financial decisions to make before humanity once again heads off to other worlds.
Post By http://www.cbc.ca/news/technology/orion-flight-a-small-step-that-may-lead-to-a-giant-leap-bob-mcdonald-1.2860647
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