That gives scientists plenty of places to hunt for exoplanets , or planets outside our solar system. As a result, estimates of how many stars there are come down to calculations of our galaxy’s mass, and estimates of how much of that mass is made up of stars. According to a new scientific estimate there are at least 100 billion planets in our galaxy, or one for every star. Using a technique called microlensing, which can reveal the mass of planets … Researchers from NASA, the SETI Institute, and others, found that there may be as many as 300 million potentially habitable planets in our galaxy alone. The discovery of the nature of galaxies as distinct from other nebulae (interstellar clouds) was made in the 1920s. Each galaxy has … By Jessie Yeung, CNN. The four galactic arms rotated around this black hole across a diameter of over 100,000 light-years. Answers (2) Akira Haley 21 August, 16:23. There are about 51 galaxies in the Local Group (see list of nearest galaxies for a complete list), on the order of 100,000 in our Local Supercluster, and an estimated one to two trillion in all of the observable universe.. 0. 0. Astronomers estimate that there is roughly one exoplanet per star in our galaxy. The eight planets in our Solar System, in order from the Sun, are the four terrestrial planets Mercury, Venus, Earth, and Mars, followed by the two … The galaxy, as it was commonly referred to, was one of the trillions of galaxies in the universe.The galaxy was a vast composite of over 400 billion estimated stars and over 3.2 billion habitable systems orbiting around a supermassive black hole at the heart of the galaxy. Comment; Complaint; Link; Know the Answer? There are at least 300 million potentially habitable planets in our galaxy, NASA finds. There are likely to be many more planetary systems out there waiting to be discovered! The following is a list of notable galaxies.. Comment; Complaint; Link; Aliana Nguyen 21 August, 16:54. Current estimates suggest there may be as many as 2 trillion—that's trillion with a T— galaxies in the observable universe. There could be as many as six billion "Earth-like" planets in the Milky Way galaxy, according to a new study. Doing the math, we can then say that the Milky Way galaxy has – on average – between 800 billion and 3.2 trillion planets, with some … Our planetary system is called the Solar System, referencing the name of our Sun, and it hosts eight planets.. A star that hosts planets orbiting around it is called a planetary system, or a stellar system, if more than two stars are present. There are infinite planets in a galaxy! Answer. Our Sun is just one of about 200 billion stars in our galaxy. +2. How Many Planets Are There In A Galaxy? Based on these calculations, scientists estimate that the Milky Way contains between 100 and 400 billion stars (though some think there could be as many as a trillion ). Of course, some stars have many planets – our own Sun … There are more than 100 billion planets in a galaxy.