On the morning of July 16, 1969, more than a million people lined the beaches and causeways around Cape Kennedy, Florida. They had come to watch the Apollo 11 mission blast off for the moon. For nearly a decade, since President Kennedy had set the goal of a lunar landing, the American people had been waiting for this moment. Some saw it as the dawn of a new age of exploration; others saw it as the end of an expensive drain on the national budget.
At the Kennedy Space Center, the families and friends of the astronauts gathered on special stands. The public had great faith in NASA, but the experts knew the odds were no better than fifty-fifty. The astronauts had spent countless hours in simulators, preparing for every possible problem. Some of the training rigs looked bizarre, like the gantry at NASA Langley that simulated lunar gravity.
But the real thing was different. Hours before launch, the giant Saturn V rocket was being fueled. Its tanks would be topped up until seconds before liftoff. The crew was a fully experienced team.
Michael Collins, the command module pilot, had flown on Gemini 10. Buzz Aldrin, the lunar module pilot, had pioneered spacewalking techniques on Gemini 12. And the commander, Neil Armstrong, had saved his Gemini 8 mission from disaster with his cool head and quick thinking. They were chosen to handle difficult problems, and there would be problems.
Every NASA mission had built on the experience of the ones before, but there was always a point where they entered unknown territory. The pressure to reach the moon before the end of 1969 had been unrelenting. The nation was confident, and launch parties were held across the country. Entrepreneurs sold souvenirs, and the mood was festive.
At the launch complex, tension was high. Wernher von Braun, the German-born rocket pioneer, had been working toward this moment his whole life. Everyone at the Cape understood how many components had to work perfectly for a successful launch. The astronauts themselves said the launch made them most anxious.
This was the sixth flight of the Saturn V, and while some had been a little rough, all had been successful. At T-minus 15 seconds, the countdown continued. “12, 11, 10, 9, ignition sequence start. ” The rocket lifted off, and just seconds into the flight, control was transferred from the firing room to Mission Control in Houston.
“Apollo 11, this is Houston. Radio check, over. ” Twelve minutes later, Apollo 11 was in low Earth orbit. Apart from a slightly rough ride with the third stage, everything had been routine.
The translunar injection and docking with the lunar module had been practiced many times before, and they went smoothly. The cruise to the moon and lunar orbit had been done twice before, and the flight manuals had been rewritten with the benefit of previous experience. The Apollo system was designed so the crew could navigate and perform engine burns autonomously, but radio ranging had improved so much that Mission Control was now giving all the instructions. Still, the crew used the onboard technology to determine their position in case of a communications problem.
Command module pilots took pride in the accuracy of their navigation. Both the command and lunar modules were equipped with the Apollo guidance computer, one of the first practical microcomputers. For most computations, there was a manual workaround, but for the complex flight path required to land on the moon, the computer was essential. Now in lunar orbit, the crew lost radio contact every time they passed behind the moon.
During the 13th orbit, the lunar module separated from the command module. The two craft adopted individual call signs: the command module became Columbia, and the lunar module became Eagle. Descent to the moon happened in three stages, each controlled by its own computer program. The first stage was the braking phase, which changed the orbit to reach a zone above the designated landing point.
During this period, the crew traveled feet first, looking up at the Earth. The next stage was the approach phase, when the Eagle tipped up into a more vertical attitude. This was when Aldrin and Armstrong got their first view of the landing point: a long, elliptical region in the Sea of Tranquility. The open plain was judged to be the easiest place for the first lunar landing.
Then unexpected things began to happen. Fuel in the lunar lander’s tanks began sloshing around. It wasn’t dangerous, but the motion meant the craft couldn’t give a clear indication of its pre-programmed landing site. Then the flight computer began sounding an alarm.
Only one person in Mission Control knew what a 1202 alarm was. A young software engineer understood that the computer was overloaded but could still handle critical functions. The mission would continue. The final part of the landing sequence was still computer controlled, but it allowed the commander to override the craft’s rate of descent and positioning.
As the Eagle headed for a field of large boulders, Armstrong took control, looking for a safe landing area. This took much longer than anyone expected. “875 feet. Guys, looking good.
Down a half. 6 forward. ”
Fuel was running low. “60 seconds.
” The alarms continued. Armstrong kept flying, searching for a clear spot. “30 seconds. ” Then, “Contact light.
Okay, engine stop. ”
The relief in Mission Control was palpable. “We copy you down, Eagle. ”
“Houston, Tranquility Base here.
The Eagle has landed. ”
“Roger, Tranquility. We copy you on the ground. You got a bunch of guys about to turn blue.
We’re breathing again. Thanks a lot. ”
Because of the distraction during the descent, no one had a clear idea of the Eagle’s exact location. After the craft was made secure, the flight plan called for the astronauts to get some sleep.
But Armstrong and Aldrin requested a change, and it was agreed. They began preparing for their walk on the lunar surface. About seven hours later, Armstrong was climbing down the ladder. A black-and-white TV camera was activated, and around the world, 600 million people were watching.
“That’s one small step for man, one giant leap for mankind. ”
This was something new. No one had thought that history would be televised with the world as witness. Some had even argued that television was a waste of time.
Now NASA was rescheduling future missions so astronauts would step onto the moon in prime time. Armstrong and Aldrin spent two and a half hours on the lunar surface. Much of that time was used for ceremonial duties, like planting the US flag and chatting with the president. The trip back to lunar orbit went smoothly.
From there, the three astronauts were back on thoroughly understood ground. The three-day return cruise to Earth was a calm period before a storm of publicity obligations that the Apollo 11 astronauts had not prepared for. Armstrong, Aldrin, and Collins were celebrated in ticker-tape parades across the United States and then around the world. The generous taxpayer funding that had kept the space program going was now in doubt, and NASA was eager to build on this wave of popularity.
But in the corridors of power, questions were being asked about the vast sums required to put men on the moon. With the last landing of the shuttle fleet in 2011, the United States, a major contributor to the International Space Station, was reliant on Russia to ferry astronauts to and from the orbiting laboratory. To get cargo and supplies to the ISS, NASA signed contracts with the private space technology company SpaceX. SpaceX’s cargo capsule, known as Dragon, has been regularly delivering hardware and consumables to orbit since 2012.
Dragon can also return from orbit. It’s a stepping stone to the company’s Dragon version 2 crew capsule, which will be able to take astronauts to and from space. Due to make its first manned flight in two years, the Dragon takes advantage of new materials and technologies to cut the cost of spaceflight. Its return through the atmosphere will use an ablative heat shield, and the current generation of Dragons return via conventional parachute technology.
The new capsule will use propulsive deceleration technology to make a pinpoint landing, enabling it to be reused. The Falcon 9 launcher’s two stages will also return to the ground for reuse. A Grasshopper technology demonstrator made its first flight in 2012. SpaceX conducted a series of experimental launch and return flights at its test site in McGregor, Texas.
The vehicle made eight successful flights to refine the autonomous return technique. The technology has been incorporated in the Falcon 9. After launching a cargo craft, the booster’s first stage attempts to return to an ocean platform. SpaceX technicians are aware that further refinements are needed.
In 2006, the European Space Agency began work on a unique star mapper that became known as Gaia. Designed to orbit the sun at a point 1. 5 million kilometers beyond Earth, it rotates, scanning our local galaxy to accurately gather positional information about neighboring stars. Two different telescopes feed images to the probe’s very large high-definition camera.
Over its five-year operational period, Gaia will rescan the same areas 70 times. As it orbits the sun, its positional change will enable it to observe parallax differences from which accurate star distances can be determined. In addition to position and distance information, Gaia will collect two different types of spectral data. One will help determine the stellar object’s speed, and the other will indicate the object’s chemical makeup.
Gaia was successfully launched at the end of 2013 and has been functioning correctly since. Its pointing and positioning are achieved by cold nitrogen thrusters that do not compromise the satellite’s thermal integrity. Gaia’s data link with Earth can handle 3 megabits per second, and it will be fed back to ESA’s most sensitive ground stations at Cebreros, Spain, and New Norcia in Western Australia.
