Solar System Sun
Terrestrial Planet Mercury, Venus, Earth (Moon), Mars
Asteroid Belt Ceres, Vesta
Jovian Planet Jupiter, Saturn, Uranus, Neptune
Kuiper Belt Pluto, Haumea, Makemake
Scattered Disc Eris, Sedna, Planet X
Oort Cloud Etc. Scholz’s Star
Small Body Comet, Centaur, Asteroid
- Touch the Sun (12/6/2019) - Remember how Icarus wanted to touch the Sun, but met his demise instead? Well, scientists at NASA wanted to touch the Sun too, but unlike Icarus, they succeeded! Better yet, they are beginning to share what they learned by doing it! Before we get into all of that, let’s go back and start at the … Continue reading Touch the Sun
- Halloween@NASA (10/31/2019) - The folks at NASA love Halloween, and they do something to celebrate every year. For example, the engineers at NASA Jet Propulsion Lab have been holding a pumpkin carving contest for almost a decade, and stories about their ingenuity invariably make it into the news. Here’s a video from Wired about their 2016 competition. Here’s … Continue reading Halloween@NASA
- Get Lost in Space! (9/14/2018) - Way back in August, in anticipation of the start of a new school year, I set out to update the pages on this site related to space. Those pages tend to be popular among the teachers and students who use Cosma, and I happen to enjoy updating them, too. It sounded like a short, fun … Continue reading Get Lost in Space!
- Milky Way Lost & Found (8/15/2018) - Have you seen the Milky Way? You may think that you have, but are you sure? Unless you live in an extremely remote area, or you’ve visited one, then you probably haven’t seen our own galaxy, the Milky Way, very well, or at all. Worse yet, you may not even realize that it’s missing. The … Continue reading Milky Way Lost & Found
- Umbraphiles (8/20/2017) - umbraphile : One who loves eclipses, often travelling to see them. — Wiktionary Yes, this is that obligatory post about “The Solar Eclipse” (NASA, Wikipedia). Of course, there had to be one — eclipses really are just too cool to ignore. You’ve already been bombarded with explanations of the science and history of eclipses, but … Continue reading Umbraphiles
- TRAPPIST-1 (2/23/2017) - You’ve probably heard that NASA has found a trove of “Earth-like” planets circling the TRAPPIST-1 system roughly 40 light years away, but just in case you haven’t, here’s a short 2 minute AP video about the discovery. Here’s another video from NASA/JPL with more explanation. Most entertainingly, here’s a 360° YouTube Video published by NASA/JPL … Continue reading TRAPPIST-1
These are organized by a classification scheme developed exclusively for Cosma. More…
star : a self-luminous gaseous spheroidal celestial body of great mass which produces energy by means of nuclear fusion reactions — Webster
Star is a luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth. Historically, the most prominent stars were grouped into constellations and asterisms, the brightest of which gained proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. However, most of the stars in the Universe, including all stars outside our galaxy, the Milky Way, are invisible to the naked eye from Earth. Indeed, most are invisible from Earth even through the most powerful telescopes.
For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star’s interior and then radiates into outer space. Almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star’s lifetime, and for some stars by supernova nucleosynthesis when it explodes. Near the end of its life, a star can also contain degenerate matter. Astronomers can determine the mass, age, metallicity (chemical composition), and many other properties of a star by observing its motion through space, its luminosity, and spectrum respectively. The total mass of a star is the main factor that determines its evolution and eventual fate. Other characteristics of a star, including diameter and temperature, change over its life, while the star’s environment affects its rotation and movement. A plot of the temperature of many stars against their luminosities produces a plot known as a Hertzsprung–Russell diagram (H–R diagram). Plotting a particular star on that diagram allows the age and evolutionary state of that star to be determined.
A star’s life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. When the stellar core is sufficiently dense, hydrogen becomes steadily converted into helium through nuclear fusion, releasing energy in the process. The remainder of the star’s interior carries energy away from the core through a combination of radiative and convective heat transfer processes. The star’s internal pressure prevents it from collapsing further under its own gravity. A star with mass greater than 0.4 times the Sun’s will expand to become a red giant when the hydrogen fuel in its core is exhausted. In some cases, it will fuse heavier elements at the core or in shells around the core. As the star expands it throws a part of its mass, enriched with those heavier elements, into the interstellar environment, to be recycled later as new stars. Meanwhile, the core becomes a stellar remnant: a white dwarf, a neutron star, or if it is sufficiently massive a black hole.
Binary and multi-star systems consist of two or more stars that are gravitationally bound and generally move around each other in stable orbits. When two such stars have a relatively close orbit, their gravitational interaction can have a significant impact on their evolution. Stars can form part of a much larger gravitationally bound structure, such as a star cluster or a galaxy. — Wikipedia
Stellar Astronomy is the study of stars and stellar evolution, and it is fundamental to our understanding of the Universe. The astrophysics of stars has been determined through observation and theoretical understanding; and from computer simulations of the interior. Star formation occurs in dense regions of dust and gas, known as giant molecular clouds. When destabilized, cloud fragments can collapse under the influence of gravity, to form a protostar. A sufficiently dense, and hot, core region will trigger nuclear fusion, thus creating a main-sequence star. — Wikipedia
Stars News -- ScienceDaily News about Stars. Read science articles and see images on the birth of monstrous stars, brown dwarfs and red giants. Consider stellar evolution and more.
- The planet does not fall far from the staron October 14, 2021 at 6:20 pm
A compositional link between planets and their respective host star has long been assumed in astronomy. Scientists now deliver empirical evidence to support the assumption -- and partly contradict it at the same time.
- Stellar 'fossils' in meteorites point to distant...on October 12, 2021 at 2:27 pm
A new study analyzes a diverse set of presolar grains with the goal of realizing their true stellar origins.
- Radio signals from distant stars suggest hidden...on October 11, 2021 at 3:08 pm
Using the world's most powerful radio antenna, scientists have discovered stars unexpectedly blasting out radio waves, possibly indicating the existence of hidden planets.
- ALMA animation of circling twin young starson October 7, 2021 at 4:22 pm
Researchers analyzed the accumulated data from the Atacama Large Millimeter/submillimeter Array (ALMA) and depicted the motion of a young twin star system XZ Tauri over three years. This 'ALMA Animation' of twin stars sheds new light on the origins of the binary stars and the planets to be formed around them.
- Astronomers may have discovered first planet to...on October 2, 2021 at 4:30 pm
In a distant star system -- a mere 1,300 light years away from Earth -- researchers may have identified the first known planet to orbit three stars.
Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.
- Astrophysicists explain the origin of unusually...on October 8, 2021 at 4:18 pm
A new study showing how the explosion of a stripped massive star in a supernova can lead to the formation of a heavy neutron star or a light black hole resolves one of the most challenging puzzles to emerge from the detection of neutron star mergers by the gravitational wave observatories LIGO and Virgo.
- NGC 1605 is an old binary open cluster, study...on October 7, 2021 at 1:00 pm
By analyzing the data from 2MASS and Gaia-EDR3 surveys, as well as images from NASA's WISE spacecraft, a Brazilian astronomer has inspected a galactic open cluster (OC) known as NGC 1605. The study, presented in a paper published September 29 on arXiv.org, reveals that NGC 1605 is not a single open cluster as was previously thought but a pair of OCs.
- A bigger nursery for the solar system's first...on September 29, 2021 at 6:38 pm
By studying isotopic variations of the elements vanadium (V) and strontium (Sr), an international team of researchers including scientists from Lawrence Livermore National Laboratory found that those variations are not caused by irradiation from the sun but are produced by condensation and evaporation reactions in the early solar system. The research appears in the Sept. 29 edition of Science Advances.
- Galactic panspermia: How far could life spread...on September 27, 2021 at 11:28 am
Can life spread throughout a galaxy like the Milky Way without technological intervention? That question is largely unanswered. A new study is taking a swing at that question by using a simulated galaxy that's similar to the Milky Way. Then they investigated that model to see how organic compounds might move between its star systems.
- Hubble snapshot of 'molten ring' galaxy prompts...on September 23, 2021 at 3:41 pm
Hubble Space Telescope's glamor shots of the universe are so revealing they nearly always have a discovery behind them.