Sashas Story. Part 3: History
see." Sasha's father said, "How did we come this far so quickly? To some
extent its simply down to good luck, but I guess it all started back in 2010
when some people at NASA made some very smart decisions. That's only fifteen
years ago, just before you were born. There wasn't much public enthusiasm for
human spaceflight or space research back then. NASA hadn't done anything really
exciting for nearly 40 years. They had built the International Space Station of
course, and repaired the Hubble Space Telescope, but nothing that sparked the
public imagination the way the moon landings had.
Space Shuttle was being retired, and the new White House administration had
invited suggestions on how the space program might evolve, and what goals it
could realistically set for NASA.
were generally agreed that Mars was a very interesting place in the Solar
System, mainly because we thought we might find evidence of life there, but
also because Mars is a world thats undergone catastrophic climate change. We
knew there would be valuable lessons for us here on Earth. The idea of a manned
mission to Mars had been discussed since the Apollo days, but no plans had ever
made it off the drawing board.
a drawing board? asked Sasha.
its like a tablet computer without the computer... It doesnt really matter.
As you know we had sent several simple robot Rovers to Mars by 2010, which were
a scientific success, but quite limited in range and capability, especially
when you consider we were exploring an entire planet. The fact is there are big
challenges with operating rovers remotely, and the biggest one is due to
eyes brightened, "you mean the speed of light problem?"
exactly right. Mars is very far away, so it can take up to 40 minutes for a
radio command to travel from Earth to a Mars rover and for a response to come
back. Its a tedious process. The rovers NASA launched in 2003 worked this way,
and ended up covering only about two miles every year. As you know I love
robots, but today most people agree that if we'd continued with just robots it
would have been decades before we discovered those Martian fossils.
who wanted a manned mission to Mars said a human geologist could accomplish
everything the NASA rovers achieved in just a week or two! But plans for manned
missions to Mars always assumed we'd land and stay on the surface. They were
immensely expensive, complicated and dangerous, and since they were making
plans when money was tight – just like now – most people had given up hope of
ever getting scientists onto the surface. My robotics friends would also point
out that manned lander missions would always be less capable than theirs
because robots didnt need to take food, water – or toilets – so youd always
be able to send more rovers to more sites for the same cost.
was also a third idea that people looked at: a sample return mission. While
we were sending ever more capable rovers, such as the Mars Science Laboratory,
nicknamed Curiosity, they were always going to be limited in the kind of
analysis they could do. So, instead of sending robot geologists to Mars, the
idea with sample return was to bring Mars back to the geologists here on
Earth. The trouble is this type of mission required a very large, complex, and
therefore expensive rover. It needed to be able to find an interesting sample,
load it into an on-board rocket that could launch from the surface, enter Mars
orbit, head back to Earth, and then a year or so later re-enter our atmosphere
where the geologists would be patiently waiting. Thats a lot of hardware to
carry to the Mars surface, and a lot that can go wrong. Plus its only one
sample. What if you picked a boring rock by mistake?
when they hit on the idea that we now know worked so well, a way to get most of
the advantages of all three approaches, while avoiding their biggest problems.
Public enthusiasm for the plan snowballed, the money was found, and here we are
original plan for the Mars Orbital Laboratory was a simple rover control room,
where geologists would operate multiple rovers on the surface in real-time from
the safety and comfort of Mars orbit. Thats how my company got involved. The
astronauts used our helmets – like
the one you tried in the exhibit – to see
through the Rovers camera eyes. For them it was like actually being on the
surface, but of course since they were actually in the orbiting lab they didnt
have to deal with the freezing temperatures, or worry about dust. Plus they
could work at a rover site in the northern hemisphere in the morning and switch
to the south in the afternoon! I should also say the Mars Sample Geochemistry
Module was added pretty quickly after planning started, and its these guys we
have to thank for finding life on Mars.
they came up with the MOL plan there were two competing camps within NASA that
could never agree. On the one hand you had the remote science and robotics
fans, which the astronauts criticized for being ineffective and boring, and on
the other side was the astronaut corps, which the science and robotics teams dismissed
as simply grandstanding Buck Rogers wannabes who sapped funds from their
the MOL proposal, the Mars remote rover drivers could see the value of being an
astronaut geologist on-site. They were now all on one side.
there was an economics argument that persuaded many. Come to think of it, I bet
youll approve of it too.
had planned to continue sending orbiters and rovers to Mars every twenty-six
months – just as wed done since the late 1990s – with some missions scheduled
decades out. With the MOL plan, we could vastly accelerate how quickly the
research was done. The idea was to spend all the money in one go. Rather than
spend 200 million a year for 16 years, put the whole 3.2 billion into
the MOL pot. It was a gamble, of course, but the idea of an intensive research
program that brought in the data decades earlier was very compelling.
NASA also decided to hand
over nearly all Moon missions to the private sector. That freed up money for
MOL, and led to the startup of many of today's commercial space companies.
They make a nice profit doing sample return projects for NASA and other
space agencies. This also marked the real beginning of the space tourism
The value of knowledge
gained from MOL is really hard to judge in financial terms. If wed not found
the fossils, Im sure youd find more people whod say it was a waste of money.
But we were lucky enough to have a series of governments who saw the value of
the program, and the money kept flowing. But I
guess my point is the MOL mission was approved because of the science return it
promised, and because it explicitly didnt need the expense of a human base on
was unconvinced. OK. I can see the advantages of operating rovers from orbit,
and the virtual reality stuff was cool, but surely it would be better to be
there in person. You havent explained why its so hard to do that. Whats so
easy about landing on Phobos and hard about landing on Mars?
with Phobos you have no atmosphere and essentially no gravity, so landing
there is a matter of moving your spacecraft close enough to touch it.
for Mars... I already mentioned that Einstein makes life difficult for us. It
turns out that Newton and Maxwell cause us headaches too. The basic problem is
the atmosphere on Mars is very thin, less than 1% as thick as it is here on
Earth. When we send spacecraft on their way to Mars they are going very fast
since theyve got such a long way to go. The trouble is when you get there you
need to slow down.
said Sasha. So you have a heat-shield and a parachute. Just like Apollo, and
just like the Mars Rovers.
works for smaller spacecraft that have a fairly small amount of momentum to
shed. But if you do the math for a spacecraft the size of a manned ship and
habitat, the atmosphere isnt thick enough to slow you down to a speed where
you can safely open the parachutes. There are ways around the problem of
course, like using an enormous heat-shield, or firing the engines to slow you
down ahead of time, but both of these require a ship much larger than the MOL.
Plus a manned ship that lands in just one place cant do anywhere near as much
science as we can today with multiple rovers. But its the guys who figured out
we could fit small rock-sample rockets on the rovers that really made this
option a winner. Once we had the orbiting lab in place, the rockets only had to
launch the samples into low orbit where a tug could capture them and bring them
back to the geologists in the MOL. There they ran tests, and directed the other
rovers to promising sites, and ultimately found the fossil."
wrinkled her nose. So how many samples did they look at in the Mars Lab before
finding the fossil?
From six different sites. And the Geochemistry Module onboard is far more
sophisticated – and by that I mean larger and heavier – than anything we could
reasonably fit into a manned lander.
basically, we got this far so quickly by arguing we didn't need the expense of
a manned Mars landing, so it's hard to convince the people who control the
money we want to do one now.
had overdone it. Sasha was looking at her feet.
course, there are plenty of people who think a manned landing is the next
logical step, and if we dont do it first someone else will. I dont want sound
too discouraging! Its just that it might not happen for a few years yet, while
we wait for those rocket scientists to work their magic. I just dont want you
to be disappointed!
OK, Dad, she said. I can be patient. But in the meantime Im going to walk on
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| Contributed by: Adrian Wyard