Die on Mars

Let the United Space Station use its camera to find Lao Mao in orbit. This was Tang Yue's last resort when he was forced to think of it. It was the last straw. The Joint Space Station is actually not suitable for this kind of work. After all, it is not a spy satellite. It does not have such high-precision optical observation equipment. It is necessary to accurately distinguish a Mars rover less than ten meters long at an altitude of three to four hundred kilometers. Only the National Reconnaissance Office's keyhole satellite can do it.

The Joint Space Station once undertook Mars remote sensing and observation missions. It was equipped with spectral scanners and synthetic aperture radars. However, such equipment was used for large-scale geological terrain detection and mapping, and it was impossible to accurately determine the position of a vehicle. The only high-precision camera on the space station is still in the Dawn module, but it has now been destroyed along with the module.

Maidong searched for telescopes and cameras in other cabins, hoping to find some useful equipment - Maidong remembered that there was an optical observation system in the Discovery cabin, which was used to assist the spacecraft in rendezvous and docking, and could It might be possible to detect the approaching Orion spacecraft two hundred kilometers away and use it to find stray dogs on Mars.

Tang Yue opened the map and marked the location of Kunlun Station on the map. "This is the location of Kunlun Station. It is 87 degrees east longitude and 12 degrees 54 minutes north latitude. It is the starting point of Operation Lao Mao."

Maidong nodded.

Tang Yue then marked the location of the Chelome probe on the map, "This is the Chelome, the end point of Operation Old Cat."

He connected the two points with a clear red line, and the computer quickly gave the straight-line distance between the two: 95.23 kilometers.

"We'd better scan every inch of land that the old cat may pass through, and we can't miss any corner." Tang Yue turned the map, and he drew vertical line segments at the two endpoints of the red line. The two line segments were divided by the endpoints. , both in length, are two kilometers long. Then based on these two line segments, he added two long sides to complete it into a long and narrow rectangle.

Tang Yue marked all the areas covered by the rectangle in red.

"Is this the area where Mr. Cat might exist?" Maidong looked at the map.

"The old cat will return immediately after finding the Chelome, so its location can only be between Kunlun Station and the Chelome landing site, that is, within the 95 kilometers." Tang Yue explained, " We expand the width of this straight line by one kilometer to the left and right... Then this corridor of 95 kilometers long and two kilometers wide is the activity range of the old cat, and its activity range should not exceed this area."

Maidong looked at the map carefully. The red rectangle drawn by Tang Yue was very conspicuous. It was a huge rectangle ninety-five kilometers long and two kilometers wide. Tang Yue's speculation was quite reasonable, leaving enough redundancy. The old cat's route might not be strictly a straight line, but no matter how many twists and turns it took, it would not go out of the width of these two kilometers.

As long as they search this area carefully, they will definitely find the old cat.

But this area covers an area of ​​190 square kilometers.

"Okay... I'll get ready. When the space station passes over your heads, I'll start taking pictures." Maidong just did it, but there was worry in her tone, "But this area is really too big, in my hands The field of view of the camera is very small when it is at the highest resolution... If you scan everything without touching the ground, the image data obtained will probably be very huge."

This is common sense. For optical observation, the larger the image, the smaller the observed area. In order to search for stray dogs on Mars, Maidong had to adjust the magnification of the observation system to the maximum. Correspondingly, the area she could observe would also be reduced to the minimum.

"The highest resolution accuracy of the optical tracker on the space station is five meters, but at this time its field of view is only as large as 2,000 square meters." Maidong calculated, "If a photo covers an area of ​​2,000 square meters, then To completely scan the entire corridor would require 95,000 photos."

This number is astonishingly large. Assuming that every photo taken by Ophiopogon japonicus can be seamlessly connected and cover all areas, it would take 95,000 photos to completely photograph this corridor, but it will definitely not be implemented in practice. If this is so ideal, the final number of photos may exceed 100,000.

There are only two people, Tang Yue and Maidong. They do not have automatic scanning, automatic shooting, or automatic recognition. Everything can only be done by naked eyes and hands, not to mention the final photo identification. The photography work alone is very difficult. It is an out-and-out major project.

What's more, we can only rely on Ophiopogon japonicus to take photos, and Tang Yue can't help.

Tang Yue thought for a moment, "If you feel it's too tiring and troublesome, we can compress the work..."

"No, no, no, I don't feel tired, nor do I feel troublesome." Maidong shook his head quickly, "I'm just saying, Tang Yue, you can't handle such a huge number of photos alone, and it's easy to make mistakes while busy, so I I can also help you share half of the burden, so we can cross-check and it won’t be easy to miss clues.”

Tang Yue was stunned for a long time before nodding.

"Okay, then let's cross-check...it's less error-prone and faster."

"Really?" Maidong blinked, his hazel eyes brightening, and there was a little bit of playfulness in his eyes.

"How long do you have to reach the skies above the Yixi Plain?" Tang Yue asked.

"Well..." Maidong glanced at the time and then at the trajectory of the space station on the screen, "There are about forty minutes left."

"Then you get ready first. I'll move the solar panels out." Tang Yue stood up and began to put on the Mingguang Armor. He locked the life support system and turned on the power switch. "This is the first time I've passed over the plains. , approximately how many photos can you take?”

"It's hard to say... The system in the Discovery cabin was not originally used to take pictures of the ground. It is a bit troublesome to operate, but fortunately it supports continuous tracking and taking pictures." Maidong made a slight estimate, "I'm effective The observation time can last about fifteen minutes, and two photos can be taken in one second after locking the trajectory."

Fifteen minutes, two photos per second, so a total of 1,800 photos.

"Remember to start scanning and shooting from the landing position of the Chelome," Tang Yue reminded.

"I got it."

Tang Yue took a long breath, adjusted his Mingguang Armor, and then stood in the hall of Kunlun Station for a few minutes, slightly lost in thought.

His eyes swept over the empty chairs at the table, looked around, and finally landed on the floor in front of him.

"I'm going out."

"Yeah." The girl waved her hand, "Go back quickly and pay attention to safety."

Tang Yue opened the door of the airlock and was about to lean out when his movements suddenly stopped. He turned around and his eyes fell on Maidong on the screen.

"Thank you Ophiopogon japonicus...I also thank you on behalf of the old cat."

"How can you thank me?" The girl chuckled, turning her eyes away, a little shyly, and pinched the Shiba Inu toy in her hand.

Tang Yue got into the airlock, and the hatch closed heavily behind him.