What are the demographics of stars visible to the naked eye?
user99379 on physics.stackexchange.com asks “Of the stars that can be seen with the naked eye, what are the distributions of each type? For example, how many are main sequence? how many are Super Red giants/white dwarfs/neutron stars…etc. What’s the distribution by mass and distance?”
Most of the brightest stars are nearby main sequence stars with spectral types B, A and F (50%, e.g. Sirius, Altair, Vega), but there are also a bunch of more distant O-type main sequence and giant stars (5%, e.g. Regor, Naos) and another big clump of red giants (about 35%, e.g. Arcturus, Aldebaran) and a few percent are distant supergiants (e.g. Deneb, Rigel, Betelgeuse). There are no white dwarfs, and definitely no neutron stars!
I have attached an image which I created by selecting 4992 bright (V 6, hence visible from a good site) stars from the new, revised, Hipparcos catalogue (van Leeuwen 2007) with a parallax and plotted them on the absolute V vs B-V colour-magnitude diagram (analogous to the Hertzsprung-Russell diagram). Also shown is a zero age main sequence for stars
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7:30pm ET! To join, head over to YouTube and check out the show’s live chat and our Discord!
Python for Microcontrollers – Adafruit Daily — Select Python on Microcontrollers Newsletter: PyCon AU 2024 Talks, New Raspberry Pi Gear Available and More! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi
EYE on NPI – Adafruit Daily — EYE on NPI Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey
