Dwarf stars are the most plentiful in our sky. But as their name suggests, they are smaller in mass and thus less intrinsically bright. Our August fundamentals will focus on some white and red dwarf stars. Although each of these stars are dwarf stars, they are more different to each other than just their color. Red dwarfs are part of the main sequence stars, and are among the most plentiful in the universe. In addition, a good percentage of the stars nearest our solar system are also red dwarfs. Proxima Centauri, our nearest star is a red dwarf. Also not as easy to see is Barnard’s Star, a red dwarf star about six light years away. Main sequence stars are burning their main fuel of hydrogen, and red dwarfs have a long lifespan as the star undergoes fusion in its core.
White dwarfs on the other hand are bright, because they are the hot dense cores of sun-like stars that have burned through the main sequence and ended up as just the carbon core of a star. White dwarfs are also commonly found with planetary nebulae, since those outer layers puff off as the star cycles from hydrogen to helium and onto heavier elements as the life of the star progresses. These white dwarfs are about the mass of our sun but compacted to a diameter of Earth. Although they are very hot, they are also intrinsically faint. Fortunately, there are about 5 white dwarfs within about 16 light years of Earth. 40 Eridani B is about 4.4 magnitude and easily visible in a small scope. Interested in taking a tour of these mighty, yet smaller mass stars? Make sure to catch our August Fundamentals meeting with our presenter, NAA member Jim Hopkins.
Focal Plane November ’24 – Searching for Gravitational Waves from Supermassive Black Hole Mergers
The October 3, 2024 NASA Universe of Learning featured discussion on gravity. One of the topics covered was searching for gravitational waves from supermassive black hole mergers. Chiara Mingarelli, PhD - assistant professor of Physics at Yale University,...
Astronomy Fundamentals – Choosing a Telescope – Things to Consider
For many new comers to the hobby, the biggest question asked is what kind of telescope should I buy? Whether it is parents nurturing their child’s curiosity, or an adult that wants to enjoy the night sky. Of course, the hobby can be enjoyed without telescopes, and...
November ’24 Focal Plane – Discovering the Stars
For millennia, humanity has looked up at countless tiny points of light in our night sky – and wondered. What are the stars, and how did they get there? How far away are they, how big are they, why do they shine? In the last few centuries, astronomers have learned a...
November’24 – Rick’s Picks
Transient Events That Can Give Us a Good Enough Reason to Get Outside and Do a Little ObservingAll month: After favoring the morning sky for much of the year, the planets’ transformation into evening targets is nearly complete as November opens, and unmistakable by...