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.
Distant giant planets form differently than...
on February 10, 2020 at 9:57 pm
Astronomers have probed the formation process of giant exoplanets and brown dwarfs by using a combination of direct imaging of these objects and custom software to model their orbits.
Supercharged light pulverizes asteroids
on February 10, 2020 at 4:22 pm
The majority of stars in the universe will become luminous enough to blast surrounding asteroids into successively smaller fragments using their light alone, according to an astronomer.
Astronomers discover unusual monster galaxy in...
on February 5, 2020 at 4:05 pm
Astronomers have found an unusual monster galaxy that existed about 12 billion years ago, when the universe was only 1.8 billion years old. Dubbed XMM-2599, the galaxy formed stars at a high rate and then died.
ALMA catches beautiful outcome of stellar fight
on February 5, 2020 at 1:41 pm
Astronomers have spotted a peculiar gas cloud that resulted from a confrontation between two stars. One star grew so large it engulfed the other which, in turn, spiraled towards its partner provoking it into shedding its outer layers.
New insights about the brightest explosions in...
on January 23, 2020 at 8:25 pm
Researchers have, after ten years, found an explanation to the peculiar emission lines seen in one of the brightest supernovae ever observed -- SN 2006gy. At the same time they found an explanation for how the supernova arose.
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.
Double nuclei in the galaxy IC 676 investigated...
on February 11, 2020 at 4:10 pm
Chinese astronomers have carried out spectroscopic observations of the lenticular galaxy IC 676. Results of these observations provide more insights into the nature of the galaxy's double nuclei. The study was detailed in a paper published January 31 on the arXiv pre-print repository.
Study investigates over 70 variable stars in the...
on February 4, 2020 at 2:21 pm
Using three ground-based telescopes, astronomers have conducted a long-term photometric monitoring of the Sh 2-170 star-forming region. The new observations have identified 71 variable stars in this region and provided essential information about their properties. Results of the study were presented in a paper published January 24 on arXiv.org.
Observations detect distortion of magnetic fields...
on February 3, 2020 at 2:10 pm
Using the South African Astronomical Observatory (SAAO), Japanese astronomers have investigated the magnetic field structure of the protostellar core Barnard 335. The new observations suggest that the magnetic field of Barnard 335 is distorted, which could have implications for our understanding of the nature of this object. The finding is detailed in a paper published January 22 on arXiv.org.
How many stars eventually collide as black holes?...
on February 3, 2020 at 1:58 pm
Since the breakthrough in gravitational wave astronomy back in 2015, scientists have been able to detect more than a dozen pairs of closely located black holes—known as binary black holes—by their collisions into each other due to gravity. However, scientists still debate how many of these black holes are born from stars, and how they are able to get close enough for a collision within the lifetime of our universe.
Image: Hubble spies bar, baby stars
on January 31, 2020 at 3:05 pm
The galaxy depicted in this image taken by the NASA/ESA Hubble Space Telescope is a barred spiral known as NGC 7541, in the constellation of Pisces (the Fishes).