The cosmos continues to expand. Growing space exists between galaxy clusters. It’s not that those galaxies are expanding into empty space, but that space itself is growing. Therefore, we do not know the precise size of the cosmos. However, we are aware of its age and its immense size.
And we know that the universe’s contents are vast. There are approximately 400 billion galaxies in the observable universe, and each can contain hundreds of billions of stars. So, it’s mindboggling. But, as we become increasingly concerned of the vast size and scope of the cosmos and its incredibly diverse composition, the possibility of extrasolar life becomes increasingly plausible.
If you people asked astronomers a decade ago about the frequency of tiny, rocky planets like Earth, many would say they have no exact answer to that question. Humans have posed this inquiry for hundreds, if not thousands, of years. We are the first generation that can genuinely answer this issue, which is quite thrilling. A planet that circles another star is known as an exoplanet. Two decades ago we saw very little about exoplanets, but that has changed rapidly.
In the past decade, we have had the Kepler Space Telescope, which has allowed us to focus on a specific region of the Milky Way. Extremely an extremely restricted field, although it is studied with great intensity. Astronomers have discovered over 5,000 planets circling various stars throughout the cosmos. Due to the abundance of planets, there is much suspicion that life may be prevalent. Why should Earth be the only planet on which life exists? Accordingly, based just on the numbers, life appears to be quite common, though not uncomplicated.
What is the most miniature collection of variables that must be measured to establish that life is the sole viable explanation? It is an ongoing, contemporary question. And it’s possible that other molecules, such as methane, directly see the existence of liquid seas, maybe through observing the green, photosynthetic color. But is that sufficient? Will, we ever be able to definitively claim that we know for sure that there is life on another planet? Everything becomes more feasible in time.
And naturally, these are only scientific inquiries. There are the more significant philosophical concerns of why capital W, whether life exists, and whether existence has a purpose. These topics are beyond the capabilities of our microscopes and telescopes, yet this form of research raises all of these intriguing concerns.
Astronauts have commented on the experience of viewing Earth from space. They have a new perspective when they view all of humanity in one place. I believe you may get a similar disorienting effect by staring oppositely. Yet, they are observing the vastness of the universe and recognizing that we are a minute part of a magnificent system.
This ability to gaze up at the sky in awe makes us human.
Considering Exoplanets and Evolution on Earth
When considering how we study planets orbiting other stars, we must note that we never view the planets directly. Instead, most planets have been discovered by waiting for them to pass in front of their host star. When it goes in front of a star, it blocks part of its light; we can observe the star become fainter and brighter as it moves away from our vantage point.
Then, we can infer, for instance, the planet’s size based on this information. If the planet is more significant, it will block more light. To comprehend the qualities of the planets, we would like to measure their diameters, their masses, and, if we combine these two concepts, their density and maybe their composition. Are they composed of solid substances like granite, like the Earth, or gaseous substances like Jupiter?
By observing the dance between a planet and a star, astronomers may determine a planet’s mass. Imagine two dancing partners on the dance floor; one is 10 or 20 or 100,000 times heavier than the other yet continues to execute the back-and-forth cha-cha. We may examine the star’s light and determine that it wobbles back and forth; we call this the wobble or Doppler method. This enables us to know a planet exists, even if we cannot see it. In addition, it enables us to determine the planet’s mass, as a giant planet would cause the star to wobble more.
Moreover, we like determining the planet’s temperature, which is relatively simple. Temperature is determined by the planet’s distance from its star, which may be inferred from its orbital period. So we’ve been able to measure thousands of planets’ size, mass, and temperature. So now we have a perfect sense of which of those planets are a little more like Earth, both in terms of being temperate and rocky, and which are not like Earth, perhaps because they have a lot of gas or are much, much hotter or much colder.
There is something immensely wonderful about witnessing the past, discovering a fossil, and being among the first humans to possess this piece of our planet’s history. But there is an even deeper beauty because if you know how to look, you may start to perceive connections. One can begin to perceive links between people, humans and other species, humans, other species, and the Earth itself. We have an evolutionary relationship with them, which is the only reason why this is conceivable.
As described, evolution is the transformation of organisms over time. These alterations imply that if we could go back in time, we would find that modern animals have a common progenitor from the past. The planet Earth is dynamic. The more we learn about biology, paleontology, and geology, the more we realize that Everything on our planet, including its species, is subject to change.