Astronomers and Astrophysicists have been exploring the depths of space for years. Researching and constructing ways to discover more and more galaxies, planets, and stars every day. With the climate change crisis many have wondered if future human existence will be located elsewhere in the galaxy. Scientists continue to look for exoplanets with similar properties and natural cycles to earth, the only question is, are there even any habitable planets out there, and will it affect the future human generations?

Over the past few years there has been an increase of discovered planets orbiting around red dwarf starts in our galaxy. A NASA science team has found an Earth size exoplanet in its stars habitable zone, meaning it’s a rocky planet able to support liquid water on its surface. This exoplanet has been named Kepler-1649 as it was found by NASA’s Kepler telescope, only it’s located 300 light years away. Kepler-1649 has an impressive list of similarities to Earth. It is 1.06 times larger than Earth and receives 75% of starlight from its host star than Earth does to the sun. Scientists predict this could mean Kepler-1649 has similar global temperatures to Earth but too much is unknown to declare it habitable, including the exoplanets atmosphere. Kepler-1469 as well orbits a red star, a star known to have flare-ups making a planets environment struggle to support life but is as well the most popular type of star in the Milky Way. The possible habitability of Kepler-1469 is an example of many, there has been an increase of evidence of such like planets that orbit around other red dwarfs in our solar system. Including Proxima B, a new close to Earth size exoplanet orbiting earth closest star other than the sun. Proxima B is in the habitable zone allowing liquid to pool at the surface, and it’s only 4.3 light years away. Still too much is unknown of Kepler-1469 and Proxima B but it does give hope for future discoveries, astronomer Olivier Guyon quotes “The closest star to us has a possible rocky planet in the habitable zone. That’s a huge deal. It also boosts the already existing, mounting body of evidence that such planets are near”

To give a visual, this is an artists conception of the surface of Kepler-1469: Credit: NASA/Ames Research Center/Daniel Rutter

The second photo is a direct visual comparison of Kepler-1469 to Earth: Credit: NASA/Ames Research Center/Daniel Rutter

Take a look at this video, it goes into further depth of discovered possibly habitable exoplanets. It as well talks about some similarities an exoplanet must have to Earth to make it habitable, and the travel barriers humans have to these planets; https://www.youtube.com/watch?v=F2-ZxJfzNVg

To understand what makes an exoplanet habitable, there must be an understanding of what a habitable zone is. The habitable zone of a star’s orbit is commonly known as the “Goldilocks Zone”. A range of distance from any solar systems star, where is a planet is located it will not be too hot or not too cold. It will be just the right temperature for the planet to sustain liquid water on its surface, and for there to therefore be life. Goldilocks can as well refer to the size of a planet. If a planet is too small, there is not enough gravity to hold an atmosphere, but if a planet it too big it holds too much of an atmosphere, if it’s just the right size, it’s gravity can hold a level of atmosphere that can support life. Types of stars contribute to the habitable factor of an exoplanet too. Our sun is a type G star and has a further goldilocks zone, meaning its goldilocks planet will only be susceptible to small amounts of radiation. Dwarf stars are type M, they have a goldilocks zone closer to them causing the concern of flare- ups and harmful emissions of radiation.

Visual of dwarf star size: Credit: MPIA/V. Joergens

Say in the future, our technology and telescopes find a positively habitable planet the human species can claim and expand on. There is still the barrier of distance, even the closest star to Earth is 4.3 light years away. Before exoplanets can be landed on, humans must figure out how to travel at light speed, but what even is light speed or a light year?

Light years are a unit of measurement for distance and not time. One light year is the distance light travel in one Earth year, which is 9 trillion km, and light travels at the speed of 300,000km. Light years can be broken down into light hours, minutes, or seconds. When looking at matter that is light years away you see it as it was in the past. As known, the closest star to Earth is 4.3 light years away, it takes 4.3 Earth years for that star’s light to reach Earth, meaning when astronomers look at it, they see it as it was 4.3 years ago. This happens when we look at all stars and planets in the galaxy. Our sun is about 93 million miles away, so it takes about 8.3 minutes for its light to reach Earth meaning we see the sun as it was 8.3 minutes ago. Scientists use the measurement of light years to observe how spaced looked in the past. The farthest object we can see is the cosmic microwave background, located 13.8 million light years away, it’s the best observation of space scientists have after the big bang.

So how can humans travel at light speed to get to these exoplanets? Achieving the speed of light has been claimed to be nearly impossible in the past. Even so, Scientists after much research and exploration, have found that particles in space are being launched at high speeds reaching 99.9% of the speed of light. Scientists have begun to study what makes these particles move fast to help improve future space missions and exploring the galaxy. They uncovered, there are three natural ways particles can gain this speed, electromagnetic fields, magnetic explosions, and wave-particle interactions. Electromagnetic fields can accelerate charged particles because the particles feel a force pushing them from the field. This natural force is comparable to the force of magnets with positive and negative charges and can launch these particles to incredible speeds. Scientists have done harnessed interactions of electromagnetic fields to create this speed in labs. Magnetic explosions are when two magnetic fields collide into one another and become tangled. The lines of the field then explosively snap back into place causing all charged particles near to be flung away at rapid speeds. Finally, wave-particle interactions happen when fields become compressed, charged particles start bouncing between fields and gain energy. Eventually these particles gain enough energy to reach a close speed of light.

In conclusion, it can be said that there are many possibilities for there to be a habitable planet in space. Of all the discovered exoplanets so far, many need to be further examined for habitability. There must be more data before any of these planets are declared habitable, including research on their atmospheres, host stars, and orbit. Future human generations do have a chance of being affected. With the beginning of experiments to achieve light speed, and the continuous advancements of technology and human health. There is certainly a path for humans to expand across the galaxy.

Bibliography:

• Brennan, Pat. “ESO Discovers Earth-Size Planet In Habitable Zone Of Nearest Star”. NASA Jet Propulsion Laboratory, 2016, https://www.jpl.nasa.gov/news/eso-discovers-earth-size-planet-in-habitable-zone-of-nearest-star.
• Childers, Tim. “What Is A Light-Year?”. Space.Com, 2021, https://www.space.com/light-year.html.
• “Earth-Size, Habitable-Zone Planet Found Hidden In Early NASA Kepler Data”. NASA Jet Propulsion Laboratory, 2020, https://www.jpl.nasa.gov/news/earth-size-habitable-zone-planet-found-hidden-in-early-nasa-kepler-data.
• Entwistle, John. “Goldilocks In Space”. NASA NES Teacher Corner, 2011, https://blogs.nasa.gov/NES_Teachers_Corner/2011/03/17/post_130038598355
• Johnson-Groh, Mara. “Three Ways To Travel At (Nearly) The Speed Of Light”. NASA, 2019, https://www.nasa.gov/feature/goddard/2019/three-ways-to-travel-at-nearly-the-speed-of-light.
• “What Is A Light-Year?”. NASA Space Place, 2022, https://spaceplace.nasa.gov/light-year/en/.