martes, 17 de diciembre de 2019

Eternal Light and Darkness

La tinaja de Guaitil y otros cuentos
M.L.Alvardo y J.A.Villalobos/EDiNexo 2018/ISBN: 978-9968-557-73-3/pág 79-93.

I descended on the Moon eight hours ago, along with two other fellow astronauts in the Nicte module, a two-stage spacecraft launched from Earth on a rocket like the Saturn V. The Nicte is similar to the  Apollo Lunar Module of the seventies, moreover larger and technologically advanced, in terms of space navigation and comfort for astronauts.
The three of us believe that without any problem, we will walk on the Moon and explore it with our rover, within a  perimeter of 3 km around the module. Also, that the food, equipment, energy and tools for scientific explorations will allow us to stay here for at least a week, and that the Nicte will take us back to Earth, when we will be ready. The entire trip was carefully planned months ago; nothing to fear.

     Day 1 (Monday, April 8, 2024)
This is the date of the landing I wrote in the log of the Nicte, including the selenographic coordinates of the site: 89 degrees South, 75 degrees West. We landed on a tiny valley 3 kilometers northeast of the edge of Shackleton crater, between this and Shoemaker crater, almost at the south pole of the Moon.
The Earth from the Moon

Lise Valley is the name I gave to this valley in honor of the physicist Lise Meithner, member of the team that discovered nuclear fusion, and perhaps because she was a woman, was not considered to share the 1944 Nobel Prize. Well, these is a commander's prerogative, when the mission returns to Earth, I will submit the name for consideration to the International Astronomical Union.

The expedition goals are to assess the conditions and prepare everything necessary for a first landing, within 18 months, inside the eternally dark Shackleton crater. In two days, we’ll climb to its ridge, go down to the bottom the next day, and conclude a thorough exploration in less than a week.
The Moon landing was precisely planned on the exact date of the new moon, as viewed from Earth and as we expected and learned in the training classes, the region is in a dim twilight in spite of the lunar phase, which does not allow to see this natural satellite from our planet. However, from the Lise Valley you can see the cusps of the neighboring craters, illuminated by the soft glowing light of the Sun. They resembled the decayed teeth of a giant whose oral cavity we can’t see, and so both will remain like that forever.
Suddenly an alarm sounds in the Nicte, and a digital clock lights up, its dial shows 16:39 (Universal Coordinated Time on Earth). Now we do not recognize the reason for the alarm, but Nicte's computer speaker reminds us:

--Total Solar Eclipse, Saros 139. The shadow cone will travel across the Pacific Ocean, enter the American continent through Mazatlán in Mexico, continue to Texas and go out into the Atlantic Ocean via New Brunswick in Canada. Its maximum will be at 18:17 UCT and will end at 19:55 UCT.--

After this message, we talk about how lucky our crew is, being the first three earthlings who will be in position to observe the path of a total eclipse of the Sun from Earth’s natural satellite. We will have first row chairs on the Moon, right at the very origin of the shadow cone that will paint with darkness a strip of umbra and penumbra on the surface of the Earth.

Paola, the first officer, tells us that from our position, on the side of the Moon that always faces the Earth, our planet looks fixed in the sky -rotating but not revolving-. That’s why we won't see the end of the since the effect of that Earth’s rotation will hide it from our eyes the Eastern United States at 19:02 UCT.

Sergei, the mission specialist is a geologist and tells us that if we were native inhabitants of the Moon (selenites but not lunatics), we would surely say that
--today is Full Earth--. 
And like on a lunar eclipse on the Earth, we are at night, notwithstanding at the south pole of the Moon we experience a soft twilight. Consequently, from the near side of the Moon, we might see the three regular types of solar eclipses on the surface of the Earth, partial, total, and annular, even hybrid eclipses.

However, Sergei tells us that a solar eclipse on the Moon, during --New Earth phase--, would be something exceptional, because of its duration, size and level of darkness. This is because the Earth would cover the Sun more deeply and the size of the shadow on the Moon is larger and the eclipse last more minutes. Moreover, the shadow bands, hues and diamond ring effect will be extraordinary because of Earth’s atmosphere and high mountains. The three of us discussed how much we'd like to be at Mare Serenitatis the date of such a type of solar eclipse.
The viewing impact we got watching the Earth rotating but fixed at a point in the sky is unforgettable. A curious rotation without moving on its orbit as if our beautiful blue marble is whirling on the finger one of those basketball players, but at the same time the background stars are slowly revolving, behind her.

     Day 2 (09/04/2024)
Today we rest, study and prepare for tomorrow’s tasks. We wrote the report on yesterday’s eclipse and review some orbital and physical data of the Moon. For example, the 5.1 degrees plane tilt of its orbit relative to the ecliptic and the 1.5 degrees obliquity of the axis of rotation with respect to the orbital plane. Because of these two conditions the sun's rays are almost parallel to the surface at both poles most of the time, and that consequently the ridges of polar craters remained somewhat illuminated.
Nevertheless, the bottom of the polar craters is completely hidden, in permanent darkness, no matter the lunar phase. We'll see that tomorrow.
To this eternal darkness contributes the faint - almost absent lunar atmosphere, perhaps the closest thing to what we know as emptiness. 
This lack of atmosphere attenuates diffuse light, which is then only caused by the reflection of the dark soil. Thus, the bodies that receive the sun's rays directly are resplendent, while those that do not receive light, as the bottom of Shackleton crater, are in total darkness. 
We don’t experience such unusual situation on Earth, since our planet atmosphere diffuses sunlight, and allows us to see a little bit of our surroundings, even if we are inside a closed room that has at least one small window.

     Day 3 (10/04/2024)
Paola and Sergei dressed in their astronaut suits, are unloading the necessary equipment from the Nicte, including the rover, that will transport them to a low wall of the crater. There they climb the slope, get to the top and conduct the first exploration of the perimeter, a walk in the park. 
I will stay, on my trousers, inside the module, to monitor and maintain constant communication with the two explorers. The next day, Paola and I will climb to the top of the crater, go down to the bottom and continue with the routine of recognition, data and sample collection.

The Shackleton is a circular impact crater, 21 km in diameter, its depth is estimated in 4.2 km. The bottom is assumed to be bumpy, with some mounds of various sizes, the central is about 50 m high. The temperature at the bottom might reach 90 kelvin and we believe that there is water ice scattered in some deposits, or mixed with the soil, but this it is uncertain. This ice possibly came from a comet nucleus that stroked the South Pole about 3.6 billion years ago and created the crater.
What we're sure of that is there we will come across something like the blackest new moon night, in the most remote place of Earth that you can imagine. To guide our steps, we will use the led lamps of our astronaut helmets, which points only in the direction of their narrow light cones.
I see Sergei and Paola driving the rover, moving away and climbing the crater a little, to a point where their inclination reaches 15 degrees. Then they park the vehicle securely and check that the remote-control mechanism is active, in case I need to retrieve the rover.
The rim of the crater is 70 m higher than the average level of the Lise Valley, so they only need to climb 52 m. At this stage they will use their personal jetpacks, which allow them to ascend or descend in the weak gravitational field of the Moon (one sixth of the Earth's value), but only for five minutes at a time, before reloading.
At 08:00 (Nicte time), I'm informed that they arrived at the top of the crater, took off the jetpacks and begin to explore the crater rim. They realize that it took them much less time than expected and make a risky personal decision that is not in the established protocol. As they are on the edge, feel rested, in clear twilight, with enough oxygen and energy, they decide to go down a few five hundred meters to the bottom of the Shackleton, but they will not let me know that change of plans.
Paola and Sergei estimate that they can go down and up in no more than one hour and that I won't notice it until they conclude, supposedly successfully, and instead of a rebuke for two, we'll have a celebration for three.
The descent and ascent into the crater were planned months ago. It will be executed in the traditional mountaineers' way we use on Earth, with feet, hands and ropes, but it requires at least five hours. Paola and Sergei know the procedure by memory, but...
Decided to change plans, the two astronauts use their equipment to secure two ropes in a crater rim rock, which look solid and firm and begin the descent.
It is 09:00 Nicte time. The strings are very thin Carbon fibers of exceptional strength and elasticity, have a length of 500 m, attached to a harness on their back, like dog’s straps and are coiled to a ring at the waist of each space suit. They are almost unnoticed and can be released and rolled up at will with three voice commands, transmitted by  Bluetooth to a small engine built into the astronaut suit. Paola and Sergei just have to say the words corresponding to three musical notes (as pronounced in Spanish, French, Italian, Portuguese, or Romanian), as follows: --do-- of 261.6 hertz to climb, --si-- of 493,8 hertz to go down, and –fa-- of 349.2 hertz to stop.
They start the descent, becomes dark at 09:15, time to use the lanterns. The altimetry indicates that they have descended 400 m. Everything has turned out simple, the walls are smooth, firm, without loose gravel and the average slope of about 60 degrees has allowed a relatively easy and fast descent. Here they take a break on a small ledge and take advantage to give me a report, pretending that they still exploring the top of the crater. I listen and save the message on the recorder of the Nicte.
However, the telemetry I get tells me that they are not on the top the crater, but I mistakenly ignored that difference, probably caused by incorrect calibration.
Suddenly something unexpected happens that I won't find out after a few hours. The rocky ledge breaks, Sergei loses his balance, suffers a severe impact on his helmet, that hurts his head and loses consciousness. He falls down the slope of the crater and descends about 90 m, until the mechanism that controls its rope is automatically activated and stops the fall abruptly. The mechanical effort of the break impact causes Sergei's rope to exceed its elastic limit, fractures and burst. Without any control, the astronaut resumes his inexorable fall, tumbling downwards, with bumps and noises that no one can see or hear, possibly ceased to exist long before reaching the bottom of the crater.
Paola visualize in her mind the terrified scene, but she can't really see anything, she can't hear anything, she can only imagines a fatal outcome. The emotion and anguish strongly alter her heartbeat, she breathes with difficulty, have an excess of saliva in her throat, she feels she is drowning, she wants to take off her helmet, but rapidly realize that if she does that she will really drown.
Thinking of her partner and somewhat confused she tries to activate the stop command several times; shouting --fa-fa-fa--, but she gets no answer, she is at rest and her sound recorder does not apply to Sergei’s mechanism. In desperation she wants to use her jetpack, but she left it on the top of the crater. She tries to establish radio communication with me, but the walls of the Shackleton do not allow a clear transmission towards the Nicte. Her only chance to survive is to escalate the inner wall aided by the umbilical cord of her rope and once there communicate what happened and wait for a rescue. She hardly makes that in three hours.
At 10:45 I get the news of the accident, I assumed something wasn't right one hour ago, but….
Paola is exhausted, only conveyed a short message, she is about to faint, and only wants to rest. She doesn't even dare to use her jetpack, to descend where the rover is parked, she's afraid and fear paralyzes her muscles and mind. Luckily all verbal communications and other data are stored on the rover and the Nicte recorder and I know where she is. I also know what to do.
It's 10:50, I set the rover's remote-control mechanism and I make it come back efficiently, returning smoothly over its own tracks reaching the base at 11:35.
While I was waiting for the rover, I collect everything is necessary for the rescue. I get on board and head off for the previous recorded site. In all this time I have not received any other messages from Paola and as far as Sergei I suppose he is fatally injured.
Arriving to the site where my two astronauts started the climbing I use the jetpack and 25 seconds later, I'm upstairs, next to Paola, with a first aid kit, including an additional oxygen tank. She's semi-unconscious, the suit looks intact but she's breathing with difficulty, looks dehydrated and weak. With a mutual effort we manage to place the jetpacks on our backs and descend towards the rover.
There seems to be a tacit understanding between Paola and me. For now, we can do nothing for Sergei, he is missing, perhaps already lifeless because of the blows received, or because his oxygen endowment already run out. Possibly he is somewhere on the inner slope of the crater, or at the bottom.
Focused on returning soon to the base, Paola and I left alone all the unnecessary equipment and quickly headed back for the Nicte.
The clock shows the 13:01 hour when we enter the safety of the lunar module. We got rid of the astronaut suits, and I continue to medically assist my first officer, she's recovering satisfactorily. We are both very tired and soon fall into a state of drowsiness that makes us sleep for several hours.

     Day 4 (12/04/2014)
Paola and I are awake and partially recovered at 03:24. Outside the Nicte you can see the eternal clarity of Shackleton’s cusps, inside it and in eternal darkness, there is a whole dilemma for us: How will we find Sergei?
Decided to complete the mission and at the same time look for our geologist, we used the rover, jetpacks and ropes to quickly move to what was left of the rocky ledge inside the crater, where the accident occurred.
The two of us continue the descent in the supposed direction of Sergei's fall, sometimes illuminating the way with the lamps.
After 20 minutes we reached the bottom and there we find an unmistakable sign of the end of our partner's fall trajectory. The battered glove of his left hand with his index finger, partially trapped in a small block of frozen water. Possibly some ice from the bottom was melted by the energy of the impact and refrozen almost immediately, due to low pressure. Next to the glove, we saw an irregular drag footprint of about two meters long, where newly removed ice crystals, mixed with fine lunar regolith and small rocks, but curiously ends abruptly.
It can be seen unequivocally, that beyond this footprint and in all directions the bottom of the crater has not been altered.
We got together, taking care to walk alone over our own footsteps, we use the lamps at full power and illuminate the scene in all directions.
Nothing..., everything seems to be unchanged five meters around. You only see the typical floor of a lunar crater, but there is no Sergei, nor any other piece of his suit, or equipment, there is no clue of its possible fate. For us it has mysteriously disappeared. --What can we do, says Paola? --
We look at the gauges of our suits and realize that there is just the oxygen needed for a quick return, this if we rise with the jetpacks, which we hope will have the power to do so.
Over a quickly stacked rocks, which we can hardly see we place Sergei's glove and Paola's radio beacon, whose --beep-beep-beep-- we begin to hear in our helmet’s speakers.
After two hours we're back at the Nicte. We take the decision that there will be no day 5 and immediately return to Earth.
After obtaining a clear sign from the Space Center and inserting the parameters of the return trajectory into the computer, we soared the crater. On the speakers of our spaceship we continue to listen that increasingly weaker --beep-beep-beep--.
Might Sergei also perceive them, wherever he is? We'll never know.
Now from up here, we only have to say hello and goodbye to our friend and fellow cosmonaut, with a mixture of sadness, respect and joy. We're going back to Earth, on a bumpy mission, almost accomplished.
Away from the eternal light and darkness of the Moon South Pole.

(Please use "comentarios" to submit language corrections, etc.)