My Little Pony: My Little Pony The Martian

"By the way," after some standard greetings, Venkat asked on the other end of the phone, "Bruce, how have you been resting recently?"

"There is no time to rest," Bruce Wu replied, "I just enjoy the luxury of a few weeks of eight-hour workdays and adequate sleep. In addition to providing advance supplies for the future Ares 6, the Sleipnir project It may have come to an end, but many other projects at JPL must continue as usual."

"We're all the same in that regard," Venkat agreed, "but seriously, you and your men have accomplished an incredible feat, and we can't thank you enough." He leaned back in his chair and continued. Said, "By the way, did you receive my memo about letting Watney and his friends perform Ares 4 MAV modifications?"

"Of course. I spent the whole afternoon and part of the evening on it," Bruce replied. "Although I don't want to pour cold water on you, I still have to tell you that the draft you made is wrong. And it's wrong. It’s more than a star.”

"Is there a mistake? What's going on?"

"The thrust-to-weight ratio of the MAV descent stage is indeed 1.2," Bruce explained, "but that's before the fuel generator converts a ton and a half of hydrogen into nearly twenty tons of fuel and oxygen. Your calculations assume that Only the thrust-to-weight ratio of the hydrazine engine itself is 1.2 when the total weight of the aircraft is forty-four tons, but the mass of a landed MAV before starting to synthesize fuel is only about twenty-six tons; and for an aircraft fully loaded with fuel For the MAV, the thrust-to-weight ratio of the descent stage thruster is actually around 0.7."

"Ah." Venkat roughly ran through his thoughts in his mind and realized that Bruce's discovery was right on target. When he calculated the gross weight of the MAV's total structure, he took it for granted that other conditions would remain unchanged and completely ignored this point. "The situation is not good. It is really not good."

"It goes without saying," Bruce complained. "After that, I tried several alternatives using Pony engines, but the results were not very satisfactory. And considering that we still have to keep the MAV cockpit equipped with Shining engines for direct flight. Earth’s backup plan is no way to continue losing weight.”

"Bruce, we still have to continue to think of a solution. Now this matter can only be left to you." Venkat paused again, "If the pony engine cannot be used on the descent stage, how can we use it?"

"We will continue to study," Bruce replied. "The best way that I can think of right now is to remove the single engine and fuel tank of the second stage and replace it with a pony engine and three tons of batteries, so that it can gradually Replenish energy. But I can't think of any way Mark and his friends can safely disassemble the engine. Even using magic is very difficult. Not to mention that the specific impulse of the pony engine is actually not as good as methane-liquid Oxygen-driven chemical engine, so we are actually exchanging the current speed increase for the speed increase that may occur in the future. I don’t know if it will work.”

"And I really don't want to add a little more non-fuel load to the first stage unless it is unavoidable. The increase in speed earned at the beginning after ignition cannot make up for the loss in the later stages of flight. In order to ensure that we planned During the ascending flight path, the first stage must consume 70% of its mass during work, don’t forget this.”

"Do your best first, and let me and Teddy know as soon as there are any new developments."

"I will try my best," Bruce sighed. "As for now, let's ask the ponies if they have any method of synthesizing hydrazine that won't kill them."

For a long time in the past, Dr. Gaither had managed NASA's satellite communications command, also known as the satellite control department, with an iron fist. Then came those uninvited alien guests, and then Mindy Parker was promoted to Chief Mark Watney Observer, with authority over Dr. Gaither. Gaither made a serious protest about this matter, but the response he received was that in addition to the Mars orbiter, NASA also has a bunch of earth science satellites, two solar laboratories, a space telescope and a Venus probe at his disposal. , complain about nothing. So Gaither submitted an application to be transferred to another department.

Gaither, now in charge of Contracting Program Relations, has repeatedly hammered private NASA contractors on the example of how the long-standing potential danger of spacesuit safety glass masks turned into an actual accident during the Sol 88 Habitat Module leak. He was replaced by Tamara Lincoln; unlike the previous Star Controller, Mrs. Lincoln did not think that Mindy was an ambitious bitch who was plotting to usurp power (not that Gaither actually said this, but he did His dissatisfaction with losing his authority is really palpable), but he regards her as a scientific worker with important abilities and due diligence.

So instead of walking up to Mindy's desk and giving her orders or dismissing her as nothing, she asked Mindy to come to the main desk to discuss the issue. "Hi, Mindy," she said bluntly, "the Meteorology Department has recently Here comes a strange request.”

Mindy glanced behind her new supervisor inadvertently, "Is it about the dust storm blowing from the Amazon plains?"

"Of course," Lincoln replied, "They want to carefully trace the source of this dust storm. Although it is not unprecedented, it is certainly not suitable for the current season." This is indeed true: generally in the southern hemisphere of Mars , large-scale dust storms all erupt in late spring and early summer; when the planet reaches perihelion, the Mars weather system can absorb the most energy. Summer in the north corresponds to the aphelion in the elliptical orbit, and the possible solar radiation heat transfer capacity decreases sharply. Therefore, summer in the southern hemisphere is when the weather is truly hot, with the highest daytime temperatures regularly reaching above zero degrees Celsius.

But then again, the giant dust storm on Sol 6 came at a very untimely time...

"Understood," Mindy replied, "but why do they ask us to do image analysis? Aren't they an entire department dedicated to Martian weather observations?"

"They're not asking us to do it," Lincoln responded, "They're asking you."

"Oh." Mindy realized that something was wrong.

"Mindy, welcome to the fast lane," Lincoln said with a few compliments. "Don't be too surprised when the Manned Systems Department asks you to help modify the design of their Sirius tandem rover."

"Then at least my degree can finally be put to use." Mindy muttered softly, unable to resist.

"What do you say?"

"Nothing," Mindy decided to end the conversation, "I'll go to work right away."

Mindy spent the first hour flipping through information on Martian weather patterns. In order to avoid being trapped in the fog of a large-scale retrospective dust storm, she must have some preliminary understanding of the possible source of the dust storm. She studied the general wind patterns on Mars to date and reviewed key writings on the Martian weather system over the years. She didn't spend much time delving into the basic principles of meteorology; her mechanical engineering studies didn't help her develop much of an understanding of things like the Coriolis effect.

Interestingly, this morning’s observations of the dust storm in the Amazon plain (the center is roughly located at 10 degrees north latitude and 170 degrees west longitude, and is moving westward at a high speed of 60 kilometers per hour) indicate its source. It's the Tarsis Plateau - it's absolutely true, and to do so you have to climb directly over Mount Olympus. However, this conclusion is completely ridiculous; the materials that Mindy came into contact with in a short period of time have shown very obvious patterns: three-quarters of the major dust storms that occurred on Mars came from the Greek plains or the northern plains area-all These low-lying areas with relatively high air pressure give dust devils a chance to rest and recharge before attacking the Martian highlands.

The Hellenic Plain is in the Southern Hemisphere; dust storms produced there only cross the equator when they grow in size. The dust storms born in the northern plains have to move a considerable distance from northwest to southeast before they meet the Martian trade wind belt and start to turn. In either case, the dust storm is unlikely to end up north of the equator, but rather far south of the trade winds.

What's more noteworthy is that although Martian dust storms can expand at lightning speed, their overall movement speed is often as slow as a glacier. And the guy we're talking about is a fly by Martian standards—comparable to the cold fronts that hit the Houston area in the spring and fall, driving thunderstorms ahead at speeds of thirty to forty miles an hour.

Everything about this dust storm was wrong. Based on her brief understanding of Martian weather, nothing was consistent with previous conclusions.

But it has eerie similarities to the disaster on Sol 6.

I finally understand why they didn't solve it internally, but wanted me to handle this problem.

Mindy pulled up the weather satellite photography of the Tarsis area the day before and began to think about it.