I ask you to build tractors, but you build rockets?

Mars, distance from Earth.

The planetary system of Mars includes itself and two orbiting satellites, but compared with the Earth-Moon system, its i ounce partners are very shabby.

Phobos "Phobos" has a diameter of only more than 20 kilometers, and Deimos "Deimos" has a diameter of only 15 kilometers, operating at altitudes of 1,300 kilometers and 8,300 kilometers respectively.

The diameter of the moon is as high as nearly 3,500 kilometers. Compared with it, these two little guys are just large meteorites. Research by scientists also believes that they are two meteorites captured by the gravity of Mars.

Their surface is not only pitted but also does not form a more regular approximate circle, so the light reflectivity is very low. On the surface of Mars, they only look like two dim star points, which is 1/12 of the moon as seen from the earth, which is about the same as seen from the earth. Like Venus.

What cannot be seen on the surface of Mars is that there is a tiny bright spot next to Deimos that shines with crystal blue light and is much smaller than Phobos.

This is the comet-Lihuo combination that is decelerating at full speed. After a nine-month journey, it arrived at Mars at least half a month earlier than expected.

When "Lihuo" was pushed by the "Comet" thruster from the Earth, only five months had passed since the last Mars opposition, and it chose the longest route to Mars.

The probe launched during Mars opposition will only take up to 6 months to arrive, and the entire process will only require engine work during acceleration and deceleration.

But "Comet-Lihuo" is different. In the past nine months, it has used two nuclear reactors and obtained solar energy. The Hall thrusters have been working at maximum power the rest of the time except for a brief shutdown when turning around and slowing down.

During the entire flight, it continued to work in the acceleration phase for 193 days. Coupled with the assistance of the chemical engine when it left the earth, the fastest speed reached 92 kilometers per second, and it could fly over 330,000 kilometers per hour.

The ground has been worried that its Hall thruster will malfunction for such a long time. After all, the situation in space is unpredictable. But fortunately, it has crossed an elliptical distance of nearly 1.1 billion kilometers safely and is still on the ground. continue working.

However, its mission was nearly completed. When it was at an altitude of 6,900 kilometers from the surface of Mars, the "Comet" shut down its engine, then exploded the bolt to energize, and at the same time, the "Lihuo"'s own thruster started. The two had been together for 9 months. Partially separated.

The ejected "Lihuo" immediately began to continue to slow down, while the "Comet" reversed its direction and began to accelerate again.

It will use the gravity of Mars to accelerate again, briefly pass Mars in the direction of returning to Earth, and return in about 5 months. If there are no problems, it can still catch up with the Mars opposition in 2018 and once again bring new detections. The vessel sets sail.

After briefly adjusting the orbit, Lihuo shut down again. It did not turn on its unbiased fuel engine until the orbital altitude dropped to about 300 kilometers. It decelerated rapidly and entered the perigee of 218 kilometers and 218 kilometers in just a few minutes. Mars' low-Earth orbit with an apogee of 294 kilometers.

…

"The fuel remaining is 45.4%, and the power supply is normal!"

"The gain antenna points normally, and the signal delay is 581 seconds!"

"The orbit deviation is 1.7% and is expected to be corrected in 10 minutes!"'

"..."

Serev looked at the dazzling red letters "PING:580264ms" on the screen, and after converting it, he couldn't help but sigh:

"Ten minutes, a full 10-minute delay, a distance of 174 million kilometers, a distance of 1.16 astronomical units. In fact, Lihuo has completed two orbit corrections now, but it hasn't even started here yet."

Xiao Okada: "Yes, it is too far away from us, but the biggest advantage of nuclear power is that it has sufficient power and a large enough platform. The high-gain antenna we use is definitely the largest among all deep space detectors, even at such a distance It can still communicate stably and return clear images even at a certain distance.”

"The outside world only knows that it will arrive in October 2018. During this year, we can safely observe Mars without blind spots."

Serev adjusted the orbital route of "Lihuo" on his computer and accurately passed through the "Plain Zero" at the South Pole of Mars.

In 1832, German astronomers Wilhelm Beale and Johann Heinrich von Madler discovered an "A"-shaped terrain feature on the surface of Mars, and then used it as a feature to establish the 0-degree longitude of Mars.

73 degrees east longitude and 69 degrees south latitude. These two numbers are the top secrets of the base, and they are more advanced than any technology.

Because its existence unmistakably illustrates one thing: it is very likely that there are aliens in the universe, and the base can be certain that there are.

Fortunately, Plain Zero is located at the South Pole of Mars, which is very inconspicuous compared to Utopia Planitia, an internationally popular location for Mars exploration. It is almost in the north and south directions.

Now, "Lihuo" will use the detectors it carries to conduct a careful search that will last for a year.

Although Lihuo has plenty of weight and space, it is very crowded because it squeezes in almost every detection equipment imaginable.

In addition to common electromagnetic wave and ray detection in all frequency bands, it is also equipped with a laser interference gravitational wave detection device.

In February last year, the Aramco LIGO Laser Interferometer Observatory detected a clear gravitational wave signal for the first time. It was produced by two black holes with a diameter of 150 kilometers that collided at half the speed. It occurred about 1.3 billion years ago. After a long journey, mankind has conclusively proved the existence of gravitational waves for the first time.

Only such a large release of energy can produce gravitational waves that can be significantly detected. The power of gravitational waves generated when the earth orbits the sun is only about 200 watts. Scientists have spent a full 100 years continuously improving the sensitivity of gravitational wave detectors.

Of course, what is on "Lihuo" is not the ultra-high-sensitivity detectors on the ground composed of laser beam arrays several kilometers apart. It is just a gadget that is better than nothing. If it can detect it, then the earth will definitely be able to receive it - at most It's just earlier.

Serev waited for ten minutes before the ground finally received the image transmission signal from Lihuo. It then took about nine minutes to completely receive the first picture.

It is a planet that glows red, but its surface is closer to orange. The photos taken by the probe's ultra-large diameter lens are very clear, fully showing the rich details of the surface of Mars.

It is not Venus, whose surface is filled with an atmosphere that flows like magma, showing a violent temper, nor is it the moon, which is so lonely and desperate, but a kind of desolation that reveals calmness. You can easily see a huge river bed that has dried up for who knows how many billions of years. .

Xiao Gangtian admired the shocking huge picture, and it took him a long time to come back to his senses and find the location of Plain Zero on it.

"The period is almost 9 Earth days, and it will take three days for the detector to reach directly above Plain Zero."

Serev: "Time is still too tight, we should still throw a lander."

Xiao Okada: "By the end of June next year at the earliest, robots will be standing on the surface of Mars."