Back in October 1989, NASA launched a spacecraft named after the famous astronomer Galileo Galilei and embarked on a 14-year mission: to explore Jupiter, the largest planet in the solar system, in an unprecedented way. The mission involved more than 800 researchers from different countries and created several firsts: the first spacecraft to orbit exoplanets, the first to deploy probes inside the atmosphere of exoplanets, and the first to observe asteroids so closely.
Galileo's journey to Jupiter began with its release from the cargo hold of atlantis, a space shuttle that was in orbit around the earth. Since Galileo didn't carry enough fuel to get it straight to the giant gaseous planet, it was devised with an ingenious flight trajectory: using a technique called gravity-assisted motion to get it to skim over Venus once and Earth twice to increase its speed and push it outward into the solar system.
In February 1990, Galileo arrived at our mysterious neighbor Venus, giving Galileo the first chance to properly test and calibrate its scientific instruments. As it passed the hellish planet, Galileo studied the thickness of Venus' atmosphere and sent back fascinating images of its toxic atmosphere. This dark, almost eerie image reveals how the thickness of Venus's atmosphere hovers over the scorching surface of the planet. 5 days after flying away from its closest position to Venus, Galileo took the image through ultraviolet filters and used blue to enhance the contrast so that we could see the structure of the atmosphere in more detail.
After receiving a boost from Venus, Galileo continued its journey to Earth, where it would complete two gravity-assisted flights. The first took place in December 1990, during which time Galileo captures this magnificent picture of the true-color Earth, which was about 1.5 million miles away, or 2.4 million kilometers away. The African continent can be seen stretching upwards from the center of our magnificent Earth, and the sunlit continent of Antarctica sits quietly at the bottom of the Earth.
As far as the eye can see, slightly rotating clouds hang over the earth. Close-up images of the Earth have also been captured, such as a bird's-eye view of the beautiful continent of Antarctica during the day and the other side in the darkness. The blue atmosphere surrounding the Earth's surface can also be seen, reminding us of how fragile our existence is.
After flying over Earth, Galileo followed a constant outward orbit and in October 1991 skimmed the edge of the asteroid belt, a vast area between Mars and Jupiter.
Galileo created the history of successfully taking the first close-up image of an asteroid ever made in the vastness of the universe. The asteroid, named Gaspra, is about 11 miles long, or 18 kilometers long, and has many severe potholes on its surface, possibly a young planet.
Sunlight shining from the right side of the image clearly characterizes the asteroid's surface, projected into scarred craters on the asteroid's surface. But there seems to be a lack of larger craters here, and scientists believe that Gaspra was once part of a large planet, but it was separated from the subject during an impact event.
After passing the Gaspra, Galileo swung inward, ready for its next encounter with Earth. He successfully completed a second flyby in December 1992, increasing his speed the last time, and bid farewell to his home planet forever. Now, Galileo has finally accumulated enough speed to begin its long journey to the outer solar system, where it will carry out its main mission.
But before it reaches Jupiter, it will first encounter another planet. In August 1993, there was a small surprise when the spacecraft passed by a second asteroid. The asteroid, named Ida, was the first asteroid to be discovered to have its own moon, later named Actyl. The massive asteroid is about 35 miles long or 58 kilometers long, while its moons are only 1 mile wide, or 1.6 kilometers.
The origin of Dactyl is uncertain, but scientists believe it may be a fragment of a larger star that split at some point in the past and formed Dactyl. After passing through The Taskyl, Galileo continued its long journey, eventually leaving the asteroid belt and entering the final stages of its journey. From here, the spacecraft had no more plans to meet before reaching the Gas Giant, but it captured historic moments from afar.
In July 1994, the spacecraft had full view of fragments from 21 comets, and Comet Shoemaker Levy 9 collided with Jupiter. Galileo could directly observe the impact and send back stunning imagery.
The four frames were captured at the moment when the comet collided with Jupiter, and the maximum impact force was equivalent to the energy of 300 million atomic bombs. Since its launch, Galileo has visited Venus, been swung twice by Earth, encountered two separate asteroids, and gained a front-row position in the comet-Jupiter duel.
After a six-year journey of 2.3 billion miles (3.7 billion kilometers), Galileo finally reached Jupiter. During the journey, Galileo also carried a small atmospheric probe that was released in July 1995 as the spacecraft entered its final approach course. The probe flew into Jupiter's atmosphere alone, descended 95 miles, or 153 kilometers, through the clouds, and vaporized after 58 minutes. Although the probe is not equipped with a camera, it collects direct data on Jupiter's local weather for the first time.
It recorded wind speeds of up to 450 miles per hour, or 724 kilometers per hour, and detected huge thunderstorms in the distance that were many times larger than those observed on Earth. Galileo's successful entry into orbit around Jupiter in December 1995 meant the beginning of his first mission. Over the next eight years, it orbited the gas giant, capturing thousands of images of incredibly fascinating atmospheres, including the famous Great Red Spot Storm. The orbital design also allows the spacecraft to complete a close-range flight starting at the spectacular icy planet Europa Europa, Jupiter's largest moon.
A magnificent picture like this shows us the full spectacle of Europa, showing off its captivating surface features. The photographs also show a geologically diverse world, covered with long linear cracks and ridges that criss-cross the icy planet. Galileo also discovered a crust hidden in the subsurface liquid ocean. Looking closer, you'll also find something fascinating, like these shallow red pits, called Lenticulae, which means freckles in Latin. These unusual holes are thought to have been caused by warmer ice churning like cold lava lamps as they moved upward from the bottom of Europa's ice shell, which of course also provides further evidence for the hidden warm ocean.
Scientists have found that the linear ridges and bands crisscrossing Europa's frozen surface are most likely caused by the strong stretching and dragging gravity between Jupiter and the moon, a force that repeatedly opens and closes the ridges, leading to these astonishingly large cracks. After Europa, in September 1997, Galileo orbited the gas giant planet 10th circle and observed the peculiar Io, Io. Io's surface environment is scary and active.
As we can see from this amazing color map, Io is the most volcanic planet in the solar system. You can see irregularly shaped mountains, layered material forming vast plateaus, and lava flows erupting from giant craters, all scattered across the bright sulfur-rich surface of the planet. This image is a close-up of a crater, interwoven with various beautiful colors, this crater was named Tupan Crater, named after the god of thunder in Brazilian mythology. It can be distinguished that the black material in the figure is cooled lava, while the yellow part is speculated to be a mixture of sulfur-containing compounds, and the red part may be sulfur gas, which floats out of the crater and condenses and covers the ground. The material is surrounded by cliffs 3,000 feet high (900 meters).
This image captures an active volcano erupting, with hot lava erupting out and adorning Ganymede's brilliant surface. The volcanic activity on Ganymede is due to the strong gravitational pull of Jupiter itself, as well as the strong gravitational pull of its large moons Europa (Europa), Genimedes (Ganymede) and Kallisto (Ganymede). Due to various gravitational tug-of-war, Ganymede was constantly pulled and deformed, causing its interior to heat up and spew out colorful material, a picture that was captured by the Galileo probe many years ago. During the eight years the probe orbited Jupiter, it took fascinating images of hundreds of Jupiter's largest moons, including Galnie De, and Calisto.
Genimede is the solar system's largest moon, and its icy surface is covered with bright new craters and darker old craters, and the frozen surface is covered with oddly shaped trenches and ridges. Scientists believe that Genimede is very similar to Europa, and beneath its hard ice shell, there is an ocean layer that may have more water than on Earth. Calisto is Jupiter's second largest moon, and as shown in the figure, it is the object with the most impact craters in the solar system. Calisto is a dark, icy world that is easily apparent to have been devastated over a long period of time, although there is some evidence that Calisto, like its neighbors, may have hidden an underground ocean of liquid water beneath its frozen surface.
The Galileo probe completed 34 orbits around Jupiter while capturing thousands of stunning images of Jupiter's clouds, rings, and major moons. Since its launch in October 1989, it has traveled a total of 2.8 billion miles, or 4.6 billion kilometers. In the 14 years of space exploration, the Galileo probe has made many "firsts" and many discoveries. But just as everything in life has an end, Galileo's mission had to end. In September 2003, the Galileo probe actively fell into Jupiter's atmosphere according to the instructions. Scientists destroyed it forever, avoiding the probe from causing any pollution on Jupiter's large moons. The Galileo probe completed one of the most successful missions ever undertaken, unveiling the solar system's largest planet, showcasing the planet's stunning details and paving the way for ambitious people on Earth to the future.
by: Seeking the island, picking the stars by hand, Pete Judah, Old Eight