STS-135 Launch Day

T minus hours, pending any delays, until the end of the era.  The next US venture into space is yet to be decided.  The shuttles served us well for the past 30 years.  Some stats:

- The fleet has traveled 537 million miles in 20,830 orbits around the Earth.

- 355 different men and women from 13 countries have made up the 848 crew launched

- 179 satellites, probes, and other components have been launched

- 52 components have been returned for analysis or repair (only the orbiter can return components)

Life spans of the Orbiters

At T-9 minutes a planned hold will end and the final steps to launch will lead up to the igniting of the solid rocket boosters.  The last 9 minutes are expected to go as follows:

Resume countdown at T-9 minutes (about 11:17 a.m.)

• Start automatic ground launch sequencer (T-9 minutes)
• Retract orbiter crew access arm (T-7:30)
• Start APU recorders (T-6:15)
• Start auxiliary power units (T-5)
• Terminate liquid oxygen replenish (T-4:55)
• Start orbiter aerosurface profile test (T-3:55)
• Start main engine gimbal profile test (T-3:30)
• Pressurize liquid oxygen tank (T-2:55)
• Begin retracting the gaseous oxygen vent arm (T-2:50)
• Fuel cells to internal reactants (T-2:35)
• Pressurize liquid hydrogen tank (T-1:57)
• Deactivate bi-pod heaters (T-1:52)
• Deactivate solid rocket booster joint heaters (T-0:50 seconds)
• Orbiter transfers from ground to internal power (T-0:50 seconds)
• Ground launch sequencer go for auto sequence start (T-0:31 seconds)
• Booster gimbal profile (T-0:21 seconds)
• Ignition of three space shuttle main engines (T-6.6 seconds)
• Booster ignition and liftoff (T-0)

 

STS-135 T-1 Days - 1 - Constellation

Orion

 

As we make our journey to the launch. We take time to ponder what will be next.  NASA has planned the Constellation as the successor to the shuttle.  The Constellation program consists of a family of rockets, capsules, and landers for a range of missions.  The primary components are the Orion Crew Module, the Altair Lunar Surface Access Module, the Ares I Crew Launch Vehicle (rocket), the Ares V cargo launch vehicle, and the Earth Departure Stage (EDS).  By designing the program with these components it can support a variety of missions.  Missions envisioned were ISS supply and support, Lunar exploration and colonization, and exploration of Mars.

Altair

The Orion Crew Exploration Vehicle is a crew capsule similar to the Apollo CM.  It is four times heavier and two and a half times as large inside to support four astronauts and more supplies.  A version called the Multi-Purpose Crew Vehicle is also planned to support longer missions needed to reach Mars or and asteroid.  It reenters and lands like the Apollo capsule, however, it has a disposable heat shield so it can be reused on up to 10 missions.

Earth Departure Stage

The Altair lunar lander also functions very similarly to the Apollo LEM.  It is also much larger.  It is able to carry a crew of four to the lunar surface and carry.  It had an equipment and supplies payload equivalent to the entire LEM.  In order to support expanded lunar missions, plans call for three configurations.  The crewed sortie mode is a 7 day excursion like the Apollo.  A crewed outpost mode permitting 7 month missions and an un-crewed cargo mode to carry supplies to a Lunar outpost.  In this mode it could land 15 tons of supplies on the moon.  Roughly equivalent to an 18 wheeler.  Prior lunar explorations determined that there is sufficient water near the lunar poles.  The plan is to land near these areas and tap into the water for life support.

With Constellation, payloads, landers, EDS, etc. will be launched by a rocket 50%  more powerful than Saturn V.  Crew and the Orion will launch separately and rendezvous in orbit to build the rocket for the planned expedition in space.  It is a flexible approach that can be adapted to changing priorities and a variety of new missions.

 

Funding for the Constellation Program is scrapped form the current budgets.  Congress is yet to determine it's fate.  I believe we will send people to beyond Earth orbit.  I hope you will witness the landing on the moon or beyond.

http://en.wikipedia.org/wiki/Constellation_program

STS-135 T-2 Days - 2 - NASA countdown is underway

STS-135 will be making the final US supply mission to the ISS.  The ISS picture was taken on the most recent shuttle mission.  Mir was departing while Endeavor STS-134 was still docked at the ISS.  Before re-entering, the astronauts in the Soyuz capsule took the first ever pictures of an Orbiter docked with the ISS.  Endeavor is inverted at the top of the picture.

We are days away from STS-135.  The official countdown is underway.  Atlantis is undergoing final preparations for launch.  In the Atlantis STS-135 photo, the gantry on the left has been rolled away from the shuttle for launch.  A few days ago, it was rolled up to Atlantis to load the cargo container into the payload bay and perform other Orbiter servicing.  See the water tower on the right.  Just prior to the engine start, the water from that tower will start dumping onto the launch pad to keep it cool and to suppress noise and vibration from the rocket exhaust that could damage the shuttle. Check the current count at http://countdown.ksc.nasa.gov/shuttle/countdown/cdt/ 

The major milestones on the countdown are shown at http://www.nasa.gov/mission_pages/shuttle/news/135_countdown_milestones.html

For example about the time you get this at 9am, they will be restarting the countdown after a planned hold that started at 5 am to remove all non-essential personnel from the launch pad.  They will begin loading liquid hydrogen ad oxygen into the orbiter fuel cell at this time.

Here in Hampton, NH, we have our own countdown going.  Mallory arrived today, from college, to prepare for her trip to Kennedy Space Center and then on to Prague for a five week school term.  Our countdown resumes tomorrow evening with packing of folding lawn chairs, binoculars, and many other items on our checklist.  A final readiness call to Julia, Andy, and Ayesha to verify we have our timetables aligned and we will hold for the last good night's sleep before the launch. We all arrive in Orlando on Thursday evening.  After a little resting, we will depart the hotel a in the wee early hours to go stake out a place to catch a few winks and watch the launch at 11:26 on Friday.  Here's hoping for favorable weather and no last minute snags.

http://www.nasa.gov/pdf/566071main_135_press_kit2.pdf

STS-135 T-3 Days - ISS 1998

Shuttle and Mir

In 1990, the US and the Soviets were still playing space race and planning separate competing space stations.  The US developed the shuttle and the Soviets built a space station, called Mir.  With the fall of the Soviet Union, the space race ended.  Budgets for space exploration in both countries were slashed.  We needed to find another way to explore space.  The International Space Station (ISS) was born.  The program started with Shuttle missions to the Soviet space station, Mir, while the ISS was being designed and built.  Cooperation, and contributions to the program were also added from other companies.  Today, the crews have come from over 14 countries that participate in the ISS.

Zarya - first ISS module (Russian)

Unity - second module (US)

Click to Enlarge

With the final module ISS will consist of 16 pressurized modules that were assembled by multiple countries and transported by Shuttle or Russian rockets to the ISS.  In 2012, the Russians will launch the last module to connect to the ISS.  In 1998, the role of the shuttle became building the ISS.  Since construction started in 1998, 37 of the 43 shuttle flights have been to build and supply the ISS.  The Russians have also made 67 flights.  It has the living space of a five bedroom home and weighs nearly a million pounds. It has been an international project.  What we all hoped when we left the plaque on the moon, that space is for all mankind.

The experiments aboard the ISS cover all fields of biology, chemistry, medical, pharmaceuticals, materials, and physics.  Much of it is basic research, in that it is learning about these fields, not directly developing a product.  This type of research is fundamental to future advances in technology.  The station also serves as a proving ground to learn about how we can live in space for the time needed to reach Mars or colonize the moon.

http://en.wikipedia.org/wiki/ISS

STS-135 T-4 Days - 1990

I was emailing with Sherry's parents about putting these messages together and how little room I have to write, compared to what I am reading to put these together.  I reflected that yesterday's post about Hubble talked about the discoveries of just 10 days of it's life.  It is booked solid every second since it launched over 20 years ago.  Nearly any picture you see of an object in space has come from the Hubble. 

The universe is so unbelievably vast and diverse the Hubble is keeping every astronomer and physicist on Earth busy analyzing their results of it's findings.  Take a few minutes and explore the Hubble.  http://hubblesite.org/.  Here are two more pictures:

After the return to flight from Challenger, the shuttle performed a busy schedule of missions leading up to the International Space Station (ISS).  We launched probes to Venus and Saturn, numerous communications satellites, increasing communications around the world.  We even had missions to Mir, the Russian space station.  Performed more Spacelab experiments and made multiple trips to expand Hubble.  The list of missions is staggering, see http://en.wikipedia.org/wiki/List_of_space_shuttle_missions. 

In 1990, Mallory was born and the family had moved to Salem to live and play at the lake.  My tech world was evolving.  We had the ability to send messages to each other at work on our computer terminals, but we still couldn't send them to other  companies.  We would get our first cell phone, which was so big, it had to be built into the car.  The Web and HTTP would be first proposed at the end of the year.  We had a Macintosh computer at home I used for records, writing, and keeping track of finances.  It had a 20 meg disk drive, about enough for 8 iTunes songs.  My current PC has 1 Terabyte disk, 200,000 times larger.  There was an Apple network, called AppleTalk to connect multiple Macintoshes to share a printer. 

I was working at Data General building computer networks.  What would evolve into the ability we all have to connect computers together was being born.  The early Ethernet was running 1,000 times faster than the 9600 bps connection we used for computer terminals, but was too expensive for homes.  It used a cable the diameter of a penny and could only support a limited number of devices.  Different companies were competing over network standards.  It would be a few more years before TCP/IP, the protocol of the Internet would win out.

http://en.wikipedia.org/wiki/World_Wide_Web

STS-135 T-5 Days - Hubble 1990

Hubble telescope

 In 1990, STS-31 launched the Hubble space telescope.  It was to provide deepest pictures into space ever.  But there was a problem.  When the mirror was ground it incorrectly accounted for the gravitational flex difference between Earth and orbit.  It was near sited.  Fortunately, the Hubble had been designed to be serviced and improved by astronauts on future shuttle missions.  STS-61 in 1993 was able to install corrective lenses to restore its vision.

Since then, four additional missions have been flown to add new instruments expanding the capabilities and modernizing the telescope.

Hubble photo before and after the correction

With the vision corrected, the Hubble has been taking pictures of the universe that could only have been dreamed.  The thing with looking into space, is that the light takes a long time to get to earth,  The further away you are looking, the longer it takes to get here, the further back in time we are looking.  You may remember something from science class about the Big Bang that started the universe we live in.  Astronomers estimate that happened over 13 billion years ago.  They talk about the telescopes as how long after the Big Bang can they see.  The graphic shows a comparison.  Earth based observatories can see about halfway back in time to the Big Bang - about 6 billion years.  The Hubble Ultra Deep photo reached to within 500 million years of the Big Bang

Comparison of Telescopes

Ultra Deep Field Photo

So is there anything out there?  Hold a sewing pin at the end of your arm as far as you can hold it.  Put the head over a completely dark section of sky, even dark to earth bound telescopes.  The Hubble telescope was pointed at a spot like that and left to absorb the minute amounts of light that had traveled over12 billion years to get to Earth. The picture of the sky was taken over a 10 day period of a spot like that.  There are 10,000 dots of light in the picture.  Every dot on the picture is a separate galaxy.  When zooming in on sections they look like the second picture.

Close up on photo

The Hubble pictures are amazing and awesome.  Take a few minutes with these sites.

Watch this video to see an explanation.  http://www.youtube.com/watch?v=mcBV-cXVWFw

Check out other pictures from the Hubble: http://hubblesite.org/

http://en.wikipedia.org/wiki/Hubble_Space_Telescope

T-6 Days - Challenger 1986 and Columbia 2003

By 1986, the Space Shuttle was falling into a groove.  Everyone felt the kinks had been worked out.  Every mission learned more about what we could accomplish in space and more about biology. materials, chemistry, and physics through all of the experiments we conducted.  We were able to launch and service bigger, more sophisticated communications satellites.  NASA had even started expanding the crews to include politicians to see the benefits first hand, a reporter to help all of us understand.  The 25th mission on Challenger included a Concord, NH high school teacher, who was to conduct classes from the Orbiter to stimulate the thrill of science and technology in children.  Even before the launch it was a memorable mission.

Challenger Explosion

The photo of the rocket trails is immediately recognizable to anyone from the time and perhaps even those of you that have come since.  Seventy two seconds into the launch, the shuttle broke apart.  The separate pieces went different directions as shown in the picture.  There was hope for quite a while that through some miracle the astronauts would survive.  News reported the tracking of the intact cockpit as it descended to the ocean.  We learned the crew had perished. 

Through incredible forensic work, we determined an O-ring on the solid fuel booster had failed, letting hot gases escape onto the external tank which in turn failed causing the entire shuttle to fall apart.  Every procedure and element of the program was review and revised.  It was two and a half years before the shuttle would "returning to flight."  No more trips for politician, reporters, or teachers.

Challenger STS-51-L Crew

It has been claimed that the shuttle is the most complex system of machinery mankind has ever developed.  Others say it takes two million miracles for the shuttle to go into orbit and return successfully and only one failure to destroy it.  We flew 88 missions over 15 years before we suffered another failure resulting in the loss of the shuttle and crew.

Columbia STS-107 Crew

Columbia had completed a very successful 113th shuttle mission, and was headed home in 2003.  As it reentered the atmosphere, we always lose contact due to the plasma plume created from re-entry.  However, this time, communication was not re-established on schedule.  The shuttle was "missing".  As the morning wore on there were reports of a debris field over hundreds of miles of Texas.  Again we learned of the crew and shuttle perishing.  Again the shuttle program spent two and a half years determining the cause, improving procedures, and taking steps to decrease the risks.  We learned that a heat tile had been broken on takeoff and the hot plasma on re-entry had entered the fuselage and caused the wing to fail.  We created procedures to inspect all future Orbiters for tile damage and had repair kits in case we found damage.  The repairs have not been needed.

"Sometimes, when we reach for the stars, we fall short. But we must pick ourselves up again and press on despite the pain."             - - President Reagan at the Challenger memorial service

http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disaster

http://en.wikipedia.org/wiki/Space_Shuttle_Columbia_disaster

STS-135 T-7 Days - Early Shuttle Missions - 1981 - 1986

Cutaway view of SpaceLab deployment

The shuttle immediately started proving it's versatility.  Between the first launch in 1981 and early 1986, it was launched 24 times among the four orbiters.  The Europeans created a modular experiment platform called Spacelab.  When assembled in the Orbiter payload bay it could include 1-5 external experiment pallets for external equipment and experiments.  Some of these could be replaced with one or two habitable modules for interior experiments.  The photos show a configuration with two pallets and two habitable modules. 

Inside of a Spacelab habitable module.

The pallets held equipment like telescopes, radiation detector, and other equipment investigating the environment of space.  The habitable modules did biological and materials science tests that assessed the micro gravity effects on things.  The Orbiter had a lot of interior space, so some missions only included the pallets and they were controlled from inside the Orbiter.  Space lab components would be sent to space on 25 missions before being replace by the International Space Station.  We learned about space laboratories.

The 11th mission demonstrated the benefit of a spacecraft able to send people to space and return objects back to Earth.  STS-41-C was sent up with two primary tasks.  First was to launch a Long Duration Exposure Facility (LDEF) that would spend over five years in orbit running experiments to be returned on a future mission.  The size of a school bus, the LDEF housed 57 experiments related to  manufacturing, propulsion, science, and electronics.

Astronauts repair the captured SMS Satellite

Once the LDEF was launched, the Orbiter maneuvered to the Solar Max satellite, that needed repairs.  The plan was for the astronaut to attach a tether to the satellite then bring it into the payload bat for repairs.  But, when the astronaut touched it to attach the tether, it started gyrating out of control.  We still had a lot to be learned about working in space.  Even though the satellite was able to be restored to control, the lessons were not forgotten.  In the second try, the astronaut was able harness it, bring it into the payload bay, make the repairs and release it.  We were now proving we could work in space.  The capabilities to work in space and the value of that was being proven.

By 1986, Sherry and I had moved to Massachusetts and toddlers Andy and Julia as the center of our life.  The Betamax had turned into the VCR.  Early versions permitted it to be carried as a shoulder bag connected to a large separate video camera.  I need to dig out the early video tapes of Andy and Julia.  Mike and I were busy building a new phone system that used a network called Token Ring to connect computers. The system could connect a computer terminal to other devices at a whopping 9600 bits per second.  Fast and progressive for the era. By comparison, my PC connection today is 100  mega bits per second.  10,000 times faster.  The computer age was coming, but we were still infants.

http://en.wikipedia.org/wiki/Spacelab

STS-135 T-8 Days - STS-1 1981

Finally, in 1981, nearly six years after the last Apollo flight, the Shuttle was ready for it's maiden flight.  It launched exactly 20 years after the first manned space flight.   I was working in Florida for Stromberg Carlson, at the time, with Mike Shaffer.  We were building computer controlled telephone systems and following the development of the Shuttle.

The first launch was halted a few moments before ignition, when one of the five control computers disagreed with the others.  After launch, there were voting procedures to break the disagreement, but before launch, it was a scrubbed mission.  They found the bug the next day and the launch was rescheduled for the weekend.  The delay permitted us to take the boat and go watch the launch from the intercoastal waterway in Titusville.

Watch this YouTube for a great launch sequence of this first launch.

http://www.youtube.com/watch?v=JSk_T_SAruI&feature=player_detailpage

Remember what I said about the orange external tanks?  Well they painted the first two white, before they figured out they could save important weight by leaving them unpainted. 

Mike and I identified with bugs related to redundant CPUs.  We were implementing the redundancy programs for Stromberg Carlson's PBX, which was the first stored program digitally switched PBX.  It used the Digital PDP LSI-11 CPU with 128K of memory.  The CPU board is shown here.  There is no memory on that board, just the CPU and bus driver chips.  The five large chips comprised the 16 bit CPU.  A real masterpiece of integration at the time.  The address space only supported 64K, but we engineered a paging memory that allowed us to increase the memory to 128K in order to fit all the software needed to control all the phone system features.  We loaded programs from a tape cartridge that took 5 minutes to load the 128K program. There was no Ethernet for computers in these days.  If they needed to communicate, like with our redundant processors, a peripheral was created that would transfer information between them 16 bits at a time, or a 9600 bit per second terminal line could be used to communicate over longer distances.  By comparison, this CPU was less than 1/10,000 as powerful as an iPhone.  The data link was 1/10,000 the speed of a current Ethernet connection.  Yet, we used it to control a 1200 phone PBX, with all the features.

http://en.wikipedia.org/wiki/PDP-11

STS-135 T-9 Days - Designing the Shuttle

Multi Stage Shuttle Concepts

First a correction.  Yesterday, Mike pointed me to a website that said the Saturn V was ignited at T-8.9 seconds.  See http://gizmodo.com/5079556/happy-birthday-saturn-v-still-the-biggest-rocket-of-all for a great slow motion video of the rocket ignition and take off.

Single Stage Concept

It took a while to come up with the design for the Shuttle.  Most of the original plans were for the entire spacecraft to be reused.  Many of the models had the first stage look something like the Orbiter so it could be piloted back to Earth.  Another model was a single stage craft.  Finally after lots of analysis, they determined that to costs to build a piloted first stage were greater than the using an expendable fuel tank.  The final shuttle is able to reuse all of the parts except the external fuel tank.  Of the components, this was the simplest to build.  It is even orange because that is the primer color and it doesn't need to last beyond the time it takes to launch it.

Enterprise in Early Test Flight

  The first orbiter built was Enterprise, named after the Star Trek spaceship.  It was built to test the aerodynamics and landing abilities.  It was expected to be retrofitted for flight, after testing but the changes made to the subsequent orbiters were cost prohibitive to rebuild Enterprise.  Enterprise was tested by attaching it to the top of a 747 and then flying it up and letting it go to glide down.  See the video of the test flight in 1977.

Glide was a generous word.  One of the pilots said it was like gliding a brick.  None the less, the orbiters all were accurately glided back to earth.  For the video of the flight, see http://upload.wikimedia.org/wikipedia/commons/4/4f/Space_Shuttle_Enterprise_747_separation.ogg

http://en.wikipedia.org/wiki/Space_Shuttle_design_process

STS-135 T-10 Days - Shuttle Program

Shuttle Liftof

As we move into the final ten days, it is time to talk about the Space Shuttle.  The Shuttle is comprised of 4 major components.  The Orbiter is the part that goes into space carrying the astronauts and the cargo.  It has three liquid fuel rocket engines that are reused on each flight.  The fuel for the engine comes from the huge orange External Fuel Tank, which is jettisoned and discarded into the ocean when the fuel is exhausted..  Mounted on each side of the External Tank are two Solid Rocket Boosters. which provide 83% of the thrust needed for liftoff.  After 2 minutes, they are burned out, get jettisoned, and are retrieved for reuse after splashing down in the Atlantic. The final component of the Shuttle is the orbiter add-on, that is carried in the Orbiter bay and varies among flights.  Atlantis will carry a Multi-Purpose Logistics Module to the space station on it's last flight.  It will be the final supply trip to the space station from the US.  The flexibility to carry and return cargo in the huge bay has been the hallmark of the shuttle program.

Orbiter Approaching Space Station

As I continue the countdown, perhaps a word about the countdown is in order.  The most frequently heard portion starts at ten.  When growing up we used the 10, 9, 8... countdown to kick off many activities.  The countdown is linked to a very long checklist of items that must be performed in a specific order and with specific timing in order for the launch to occur.

Shuttle Final Countdown

The shuttle countdown begins at T-72 hours with the team called to their stations.  As the time ticks down, the shuttle is fueled, the astronauts board, all the equipment is checked, and everything else that has to be done. T-0 is liftoff.  With the shuttle, the main engines on the orbiter are ignited at T-6.6 seconds.  Huge bolts hold the shuttle to the pad as the engines build power in preparation for liftoff.  At T-0, the solid rocket booster on each side, are started and immediately provide the thrust needed to take off.  The bolts are exploded and off it goes. 

The Saturn V was ignited at T-3 seconds.  I remember watching TV videos taken at the bottom of the launch pad that showed the rockets firing and the latches holding it down as it built up power.  Then at the zero count, the latches pulled back and the rocket would start to lift.

http://en.wikipedia.org/wiki/Space_shuttle_launch_countdown

http://science.ksc.nasa.gov/shuttle/countdown/count.html#T-06H00M

STS-135 T-11 days - Apollo Soyuz - July 1975

The National Air and Space Museum display of Apollo–Soyuz

The final Apollo flight would be in July of 1975.  We were on speaking terms with the Soviets.  A political era of "detente' was underway where the US and the USSR were trying to learn how to cooperate.  It was a huge step forward from the fear during the moon race.  These talks resulted in the first weapons treaties between us to limit the number of nuclear missiles, biological weapons and other weapons both sides were developing that had the capability to annihilate all life on the planet.

Soyuz spacecraft as seen from Apollo CM

In this project we developed a docking module that could adapt the incompatible docks for each spacecraft as well as to interface between the incompatible atmospheres in each spacecraft.  Working together to do this was unheard of.  It required trust that the two countries were struggling to comprehend.

It was several more decades before the cold war would be over, but these steps started to pave the way.  It would have been an unbelievable dream at the time to think that someday we would work in cooperation with the Soviets to build a space station or that we would be sending our astronauts to the space station on Soviet spacecraft.

Betamax tape

Also in 1975, the very first home video product came to market.  Sony's Betamax began a revolution.  For about $1000 in 1975 dollars, you could buy a device that could record a TV show and play it back.  This was a capability that had only been available in TV studios.  Although this was so expensive that only the very wealthy could afford it, the home video revolution was launched.  It would not be very many years before this was affordable.

http://en.wikipedia.org/wiki/File:Apollo-soyuz.jpg

STS-135 T-12 Days - Skylab 1973 - 1974

Skylab as Apollo approache

After the moon missions, NASA and the nation struggled to select the next challenge.  The Apollo/Saturn V was a powerful combination and held options for further exploration.  However, the huge budget that funded the moon program was past.  Using parts that had been built for Apollo, a few more missions were designed to expand our scientific knowledge and determine the limits of space travel.  NASA developed our first real space station from an upper stage of the Saturn V  They called it Skylab.  Then they used the Apollo SCM to ferry astronauts to and from Skylab in three missions spanning about 9 months in 1973 and early 1974.

In comparison to all prior spacecraft, Skylab was huge, check out the drawing.  The astronauts had room for many experiments and living facilities to work for extended periods.  The third mission lasted 84 days, may times longer than prior records.  During the Skylab flights we learned to make repairs on spacecraft already in flight,  It included many EVAs to perform experiments and make repairs.  The most critical repair was in the first mission to fix a stuck solar cell wing that failed to deploy.  Without it deployed, the Skylab would have been unable to conduct the subsequent missions.

Cut-away view of Skylab, docked with Apollo CSM

As much as Skylab was advancing our understanding of living in space.  It was expensive.  The space shuttle program was getting underway and it needed the funds.  The third and final Skylab mission concluded in February 1974.  There would be one final Apollo flight before the space shuttle.  Although Skylab had supplies to support astronauts for over a year, we could not afford the cost of that program.  We were ending an era in space and the next would be years away.

Our first space station had been a success, even if only for a brief time.

By the way, in 1972, about this time, the HP-35 became the first pocket sized scientific calculator.  It cost $400, then.  Although expensive, it spelled the end of the slide rule and became the standard that all engineers had to have.  Advances occurred so fast, that by 1975, the HP-35 was discontinued for more powerful models.  My first was the HP-55.

http://en.wikipedia.org/wiki/Skylab  http://en.wikipedia.org/wiki/HP-55

STS-135 T-13, Apollo14-17 1972

We made 4 more trips with increasingly successful landings.  In December 1972, four years after Apollo 9 had made the first trip to the moon, we sent the last men to the moon. 

Lunar Rover - Apollo 15, 16, & 17

Starting with Apollo 15, the LEM engines were made more powerful, enabling it to carry the additional weight of the Lunar Rover, which was a go cart type of vehicle permitting the astronauts to travel further from the LEM.  Using the Lunar Rover, the astronauts of Apollo 17 traveled over 20 miles on the surface collecting 110 pounds of rocks and soil.  They stayed on the lunar surface for three days, running a long series of experiments.  Each of the EVAs on the surface lasted over seven hours, contrasted to the two and a half hour EVA of Apollo 11.  We had come a long way.

Last Trip to the Moon, Schmitt, Flag, & Earth

The race to the moon had solidified a country that had a true concern over the threat of the Soviet union.  As the moon program ended, I was in my freshman year at MIT.  MIT had been responsible for the guidance systems for the missions and many of the students ahead of me had worked in the labs.  I remember the dismantling of labs and facilities that had been used for the space program, and in fact still have parts that were salvaged from equipment used in the program.  We were moving on to a new era and new challenges.  I have not seen the prolonged dedication and focus to a national objective since.  The stunning magnitude of this accomplishment is profoundly memorable.

A plaque left on the ladder of the descent stage of the Apollo 17 LEM, Challenger reads:

Here man completed his first explorations of the Moon December 1972 A.D. May the spirit of peace in which we came be reflected in the lives of all mankind.

Next time you are looking up at the moon some evening, pause, look at it carefully, and consider what it took to make 9 manned trips to the moon and land 12 people to explore and return. Perhaps in your lifetime, people will travel to the moon again and this plaque will once again be seen and read by a new generation.

http://en.wikipedia.org/wiki/Apollo_program

STS-135 T-14, Apollo 13 - 1970, "Houston, we've had a problem."

Apollo 12 and Surveyor 3

Just four months after the first moon landing, Apollo 12 followed the path to the moon.  This time a few of the kinks were worked out.  They figured out that Apollo 11 landed so far off course due to a miscalculation in the angle of the decent burn.  With that corrected, Apollo 12 landed that was so accurately that they were able to walk to the Surveyor 3 probe that had landed years earlier and retrieve some parts to take back to analyze.  Remember, I told I would explain how the picture of Surveyor 3 was taken on the moon.  See the picture of the astronaut Conrad, Surveyor 3, and the LEM in the background.  So close a landing was unbelievably accurate.

Apollo 13 SM showing Damage

The third landing mission to the moon, Apollo 13, lived up to its unlucky number.  Two days into the trip to the moon, there was a bang, heard and felt by the crew.  Listen to the attached audio, of the well know, "Houston, we've had a problem."  The extent of the damage was not fully known, but after investigation, they determined that the command module had lost it's oxygen tank.  This had far reaching consequences.  The side effects were that the fuel cells could no longer create power, they could not remove the carbon dioxide from the cabin, the SCM rockets were inoperable, and in general the command module became useless.

The LEM was called to duty to save the astronauts.  Without it, the spaceship would have been doomed.  A contingency plan was put into action to have the spacecraft slingshot around the moon and back to Earth.  The command/service module was nearly useless.  The details depicted in the movie are very accurate.  Watch it.  The picture shows the CO2 scrubber they highlighted in the movie.

CO2 Scrubber Mod in the LEM

It was a hair raising few days.  It was horrible to think that the astronauts could easily be stranded.  We followed the news continuously for the three days it took to swing around the moon and carefully aim for the reentry and landing in the Pacific.  Through the ingenuity of thousands of people, the LEM was used for rocket propulsion, living quarters, and life support through the trip to the moon and back to Earth.  It was an incredibly lucky break and a masterminded adaption of the equipment to save the crew.

When the service module was jettisoned towards the end of the voyage, they were able to take the picture that showed the entire side blown off.  That was the first they saw of the severity of the damage.  It was truly miraculous that they survived.  Really, rent the movie.

http://en.wikipedia.org/wiki/Apollo_13