'Sojourner' was the first successful rover mission on mars which landed on 4th July 1997. It was designed to last for 7 Mars days and could be extended up to 30 Mars days. Sojourner lasted for 83 days on mars(85 Earth days.)

This was followed by Rovers: 'Spirit' and 'Opportunity'. The Spirit’s mission was planned for 90 Martian solar days(92 earth days) but because of winds cleaning the sand over its solar panels, it was able to continue the mission for six years. Opportunity rover was operating from 2004 up until 2018 and traveled just over 45 km.

It's been said that ‘what a rover could do in 6 months, a Man can do in 2 hours.’ If this holds true, A man could have done the same in less than 2 days. But rovers have also allowed us to discover key ingredients to life such as oxygen, nitrogen, hydrogen, carbon, sulfur and they have also measured radiation levels on Mars so that when we send humans, we already have a better understanding of the environmental conditions that we will be exposed to.

Rover Spirit was stuck in a region of soft soil during its mission on the surface. In order to get Spirit unstuck, Engineers from NASA's Jet Propulsion Laboratory had to put an identical rover on Earth in as close to the same situation as possible including a reduction in gravity.

This highlights an advantage of human consciousness against a machine running with codes. In addition, A human would not have to wait for signals from Earth to make the decisions to get out of a complex situation. These signals take anywhere from 4 minutes to 24 minutes depending on the distance from Earth to Mars. (Closest: 54,556,762 km and Farthest 400,762,656 km)

If we send humans to Mars, we can rapidly conduct our experiments and discover possibilities of staying on the surface. We can drill the Martian polar ice caps to look into its past and seek martian life even if it exists in a microscopic form. We will also be able to find out if liquid water exists below the surface and possibly use the same in the future for humans staying on the Red Planet. 

The nearest spiral galaxy to us known as ‘Andromeda’ or ‘Messier 31’ about 2.2 million light-years away is on its way to collide with our Milkyway galaxy in about 4.5 billion years from now. The sky that we are used to seeing at night is about to get spectacular!

The way scientists predict this event in the distant future is by observing the movement of stars in Andromeda with respect to the galaxies in the background using Hubble Space Telescope. The blueshift in the electromagnetic spectrum of the incoming light waves from M31 suggests that the stars emitting the light are approaching us with a speed of about 110 km/s. Why won’t it just fly past Milkyway and not collide into it? Because the tangential velocities of the stars are measured and found to be extremely small compared to the speed of approach. So it is sure to bump into us. Time to buckle up as we enter into a galactic roller coaster. 

Representations of the galaxies seem to be a very dense spiral collection of stars but in reality, the interstellar spaces are mostly empty. It is safe to assume that our solar system at the time of collision would remain intact. Alien solar systems would fly past solar systems in our galaxy as the core of M31 and Milkyway come closer and closer. Both the galaxies have a supermassive black hole at their centers. The new center of ‘Milkdromeda’ galaxy will be formed by these two supermassive black holes merging into one and sending out ripples across the fabric of space and time. A great time to detect Gravitational Waves coming from not too far!  The orbit of our solar system around the center of the Milkyway would be distorted and we would now have a new center in a bigger galaxy. If humans are still here on Earth during this event, the sky would be really different but would mostly look the same for human generations. Because our timescale is very very tiny compared to the timescales of galaxies in the universe.

If there is going to be a new battlefield in the near future, it is going to be outer space. Here on earth, we have developed tonnes of weapon systems designed specifically to be lethal under atmospheric conditions and taking into account the gravitational force which cannot be ignored. All the Guns, Aircraft, Missiles, Submarines, Battleships are designed according to the conditions they will be operated in. can these same weapons systems work in space just as effectively?

Imagine a soldier in space, Firing bullets through his gun that he uses on earth. ‘Every action has an equal and opposite reaction’. Hence, the force exerted by the gun on a bullet to push it forward will be experienced by the soldier in the opposite direction. Same as on Earth right? Except now he has nothing to hold on to. The more he fires, the more recoils will be experienced and the faster he will move backward. (Something that doesn’t seem to occur in Call of Duty Ghosts. Sorry C.O.D. )

Then what weapons are useful in space if not guns?. Lasers! It would be very lethal in space even for thousands of kilometers. It is an electromagnetic wave with immense energy capable of traveling at the speed of light! No chance of dodging it even if the target is 10,000 km away. How about a dogfight between spaceships? Here on earth, it is better to be behind the enemy aircraft chasing him. One should not try to follow an enemy in space, it can just rotate and shoot back at you while moving in the same direction i.e away from you. Same laws of physics but a very different environment.

I hope to see no wars in space. But it seems inevitable considering the fact that we cannot be peaceful on our planet.

Can a machine capable of changing the curvature of space be used as a weapon?

We, Humans, have developed 5 senses throughout our evolution on this planet. Vision, Taste, Smell, Hearing, Touch. These allow us to perceive the nature around us as we experience it today. But are we able to see, feel, or experience everything that nature offers to us with these senses? The answer turns out no! We can’t! For example, How many basic colors are there that we can see… VIBGYOR (Violet, Indigo, Blue, Green, Yellow, Orange, Red)… Easy right?

Now have a look at the Electromagnetic spectrum. We, Humans, are only able to see a tiny portion of this wide range of wavelengths that are there around us… Everywhere. All those 7 colors are in that small section. And we have thousands of color shades produced from those 7 basic colors. And nature is already so diverse and beautiful because of it.

We had to develop tools and techniques to understand that there is more going on in the universe than just VIBGYOR. All those Ultraviolet and Infrared wavelengths are being employed in our daily lives. Everyone knows how X-rays work and Microwave is like a college student’s best friend. What if we could actually see a larger portion of this spectrum? What colors are we not able to see? What would nature look like with those unknown colors?

Related Links

https://www.miniphysics.com/electromagnetic-spectrum_25.html

12,740 km is the diameter of Earth. The surface area of about 510 million square km. About 8 billion people living on this surface, now jump to 400 km above the surface of the earth. this is the distance where the space station revolves around our planet. The Earth seems to be huge for us from here!

There are a total of Eight Planets. Alright, Nine! If you insist on adding pluto. Think about 1 star having 8 planets revolving around it. That’s our solar system. Now blow your mind by searching for the possible number of stars in our Galaxy, the Milky-way. 25,000+ crores of stars. That’s around 200,000 crore Planets if we assume 8 planets revolving around each of those stars. We haven’t even been outside our galaxy yet.

For those who don’t know what a generation ship is… it is currently an imaginary space ship large enough to hold hundreds and thousands of people and all the supplies and technologies needed to survive in space for thousands of years as it travels to destinations across the galaxies.  

For now, this massive ship is a thing of the future. But just imagine if it was real and you were born on one of such humongous ship. The world would be as big as the ship itself and you will always look outside the glass panes wondering where we are heading and when will we reach there... Will I be alive when it happens?

The same places to visit and the same things to do over and over again and never knowing what living on a planet feels like… Gravity aboard the ship wouldn’t be possible unless the ship is spinning in space… or will there be an advanced technology to generate gravity in some weirdly unthinkable way? Would you like to be on one of such Generation ships?