Space researchers usually focus on our own star system, however Alpha Centauri has been gaining attention, with the hopes to possibly be visited. The article, “Alpha Centauri: Why Our Neighboring Star System Holds So Much Potential” from space.com explains our nearest stellar neighbor has been gaining a lot of attention ever since the announcement of Breakthrough Starshot, a mission backed by Stephen Hawking, Yuri Milner, and Mark Zuckerberg. Being the closest star system to our sun, it is still 4.37 light-years (25 trillion miles) away from Earth. There are thousands of exoplanets in the universe, with many of them being in orbit in habitable zones, meaning they have the potential of having liquid water on the surface. Project Blue’s focus is to see one with our own eyes and to take the first photo of an Earth-like planet. Alpha Centauri contains two stars similar to our sun, Alpha Centauri A and Alpha Centauri B. Just earlier this year an Earth-like planet was discovered in the star system, known as Proxima b. This planet is believed to be orbiting in the habitable zone, with the hopes that the planet could support life. This discovery is what sparked Breakthrough Starshot to announce that it is focusing on traveling to Proxima b as soon as the technology is available.
Before reading this article, I never knew how close another star system was to us, especially with the possibility of an Earth-like planet. Its strange that this never had some big headline yet the finding of TRAPPIST-1 was announced all over even though it is 39 light-years away. Alpha Centauri has a realistic possibility of being traveled to at some point in the future while visiting TRAPPIST-1 would be a much, much more difficult challenge. I am very surprised of the three people who are funding and backing up Breakthrough Starshot. I’d expect Stephen Hawking to be involved in a project like this, since he is a cosmologist, but Yuri Milner who is a rich entrepreneur and Mark Zuckerberg who is the CEO of Facebook just seems a little random to me. However, this project will cost a great amount of money at an estimated 100 million dollars, which explains why a billion dollar entrepreneur is helping fund it. This project wouldn’t be possible without the money, but it also wouldn’t be possible without knowing how far away the stars are, which relates to our 11th conceptual objective. If astronomers didn’t understand the distance of stars, then Breakthrough Starshot may be sent towards TRAPPIST-1 instead of the much closer Alpha Centauri. As we learned in class, scientists measure the distance of stars by calculating their parallax angle.
The parallax angle is the top angle joined by the two longest sizes as shown from our Lecture-tutorial notes. By figuring out the parallax angle, then one can figure out the distance of the star. Because the parallax angles are so small, they are measured in a unit known as arcseconds which one arcsecond is 1/3600 of a degree. Astronomers also use what is known as a Parsec as the unit of length to describe a star’s distance. One parsec is when a star has a parallax angle of one arcsecond. There are two planets shown on the image from our lecture-tutorial; planet A and planet B. Planet B is farther away from planet A, and as question 13 asks which star would have a larger parallax angle, planet A has the larger angle because its closer. Even though using the parallax angle is a useful and accurate way of measuring star distance, there is a draw back. Since the angles are so minuscule, measuring stars angles that are several light-years away would be impossible. As we were shown in class, one arcsecond (in comparison to using our hands to find out the degrees of the moon) would be the size of slicing one finger 60 times, and then take one of those slices and cut is another 60 times. That really shows how small of an angle scientists work with and can clearly understand how it would be difficult working with stars with even smaller angles.