To understand speed in space, first, we have to understand the term “time” and how it works. From a physicist perspective, time can be defined simply as the movement of something and that something, an interval, and that something is nothing but the hyperfine transition frequency of the cesium-133 atom, which is expressed in Hertz to calculate or you can say to count 1 second, which is an Itanium SI (International standards of units) definition of time. A moment of something (say, photon particles) which can be measured is called time. Now, how does time work in space-time?
In 1905, Albert Einstein came up with the theories of “Special Relativity” and “General Relativity”. These are some of the best theories that have ever been published and on which modern and classical physics are based or work. He explained time dilation and how speed affects not only time but also mass and space. He defined the relationship between energy, matter, and mass. E = MC*C, where E stands for energy, M for small mass, and C for speed of light. He also explained that time is relative and it moves relative to the reference point or the observer. Whenever an object is in motion, it experiences some time dilation, which means that if an object is going or moving very fast, then the person on that object or the object itself (clock) experiences time more slowly than when the object is at rest position.
To understand this, consider an example of two people, one who is a 15-year-old girl named Maria and another who is a 15-year-old girl named Chioa, both studying at a high school. One day, Maria left school and went on an ISS spacecraft (international space station) for a mission and traveled at the speed of light for almost five years. And when she returned years later, she would have aged 5 years for the 5 years she spent traveling through space. As Earth is moving at a much slower speed as compared to light, her friend Chioa would be 65 years old on Earth. In simple words, time moves slowly in the space-time dimension, and it almost freezes if you travel at the speed of light through space. This happens because of the space-time fabric. As space, the universe, and the spacecraft on which Maria was traveling are all moving very fast as compared to the earth, the earth’s time clock is taken as a reference point to show the relativity difference between the two. But currently, we don’t have the technology that will help us travel in space at the speed of light.
Which leads us to another question: how fast can we travel through space?
As of now, we have been able to travel through space at about 0.001% of the speed of light. On August 12th, 2018, NASA launched an unmanned rocket named Parker Solar Probe into space aboard the United Launch Alliance Delta IV Heavy Rocket. The probe was sent in a circle or to revolve around Venus to capture necessary information regarding the planet. The probe is circling Venus, either directly using Venus’s gravitational field or slingshotting itself directly towards the Sun. It is calculated or estimated that by the year 2024, it will reach a close maximum speed of 430,000 miles per hour (around 692,000 kilometers per hour).
The fastest recorded manned mission was Apollo 10. It occurred in early 1969. The Apollo 10 mission was handled and organized by NASA and was sent to the moon with some crew members. And while Apollo 10 was returning from the moon, the spacecraft vehicle consisting of crew members reached a maximum speed of 24,791 miles per hour (around 39,897 kilometers per hour). The landing was successfully handled and it was a successful mission, leading to another Apollo 11 Moon Mission.
SpaceX’s CEO, Elon Musk, has officially stated that he is working on several Mars civilization projects and is planning to send humans to Mars by the year 2026, SpaceX is building a spaceship that can travel at a maximum speed of 25,000 miles per hour (around 40,000 kilometers per hour). And if SpaceX and Elon Musk succeed in this mission, then we will break Apollo 10’s fastest manned mission record.
However, many space research organizations, including NASA, are working on developing next-generation spaceships and spacecraft that can travel at much faster speeds than we currently have, including the construction of numerous hypersonic rockets and spacecraft. The Orion Spaceship, working on gravitational or gravitational spacesuits, G forces, the outlet of a spacecraft that damages or destroys the rockets by meteorite rain, acceleration speed, and cosmic radiation. Many researchers and scientists are working on several projects to come up with an idea that will allow us to travel through space at the speed of light, without causing any cascading or hazardous effects to our human bodies. Engineers are working on various antimatter-fueled engines that will help us travel much faster through space. According to experts, it would take another 50 to 60 years for us to build a spaceship, rocket, or spacecraft that would accelerate over several periods of months or years.
There are other theories claimed by famous physicists, scientists, and mathematicians that could allow us humans to nearly travel through space at the speed of light, i.e. approximately 299792 kilometers per second. In the Hadron Collider particle accelerator, an example of this theory is the electromagnetic field theory, electromagnetic field accelerates constituent particles at a relative speed. If we are somehow able to construct a spaceship’s engine with this theory, which can travel at the speed of light without collapsing or destroying the spaceship, then we might be able to create a next-generation spacecraft. Another theory is that of magnetic explosions. Magnetic explosions constantly occur in space. They are twisted magnetic fields that forcefully snap and shoot particles and waves across space. Wave-particle interaction is another exciting theory that might allow us to travel through space at the speed of light.