Welcome to another edition of Constellation Friday! Today, in honor of the late and great Tammy Plotner, we take a look at “the Twins” – the Gemini constellation. Enjoy!
Space News & Blog Articles
“Coma” comes from the Greek word for “hair”, and it’s also the origins of the word comet. When comets appear in the sky, they don’t look like a normal star. Instead, they are surrounded by a glowing halo, and sometimes that halo appears to trail behind them, like long hair in the wind.
In globular clusters you will find a lot of older, redder stars packed closely together. In many ways, they’re the retirement homes for the galaxy.
The study of extrasolar planets has revealed some interesting things in recent decades. Not only have astronomers discovered entirely new types of planets – Super Jupiters, Hot Jupiters, Super-Earths, Mini-Neptunes, etc. – it has also revealed new things about solar system architecture and planetary dynamics. For example, astronomers have seen multiple systems of planets where the orbits of the planets did not conform to our Solar System.
What fills the vast spaces between the stars? Mostly nothing – those expanses would register as a vacuum in a laboratory here on Earth. But it’s not completely, totally, 100% empty. If you look closely, and wait long enough, you’ll see a beehive of activity.
The highly anticipated Europa Clipper mission, set to launch in 2024, will investigate Jupiter’s moon Europa. This icy moon with a subsurface ocean is considered one of the most enticing places in our Solar System where life might exist. To look beneath Europa’s icy crust, the Clipper mission has a host of instruments looking for plumes and ‘hot spots.’
Located in the Okanagan Valley outside of Penticton, British Columbia, there is a massive radio observatory dedicated to observing cosmic radio phenomena. It’s called the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a cylindrical parabolic radio telescope that looks like what snowboarders would call a “half-pipe.” This array is part of the Dominion Radio Astrophysical Observatory (DRAO), overseen by the National Research Council (NRC).
In the upper reaches of the Earth’s atmosphere, the intense UV and X-ray radiation from the Sun bombards molecules and atoms, causing them to split apart. The resulting positively charged nuclei are called ions, and the free electrons are called…free electrons. These charged particles behave differently than normal neutral molecules, especially when it comes to how they interact with radio waves.
China’s Chang’e-5 lunar lander has found evidence of hydroxyl (OH) on the Moon. Hydroxyl is a close chemical cousin of water, H2O. While several other orbital missions have detected OH on the Moon previously, Chang’e-5 marks the first time it has been detected by a spacecraft sitting on the lunar surface.
A central aspect of galactic evolution is that they must eat or be eaten. Dark energy strives to push galaxies apart, but gravity tries to pull them together. As a result, galaxies tend to form into local groups. As these superclusters of galaxies become more isolated due to cosmic expansion, they gravitationally turn on each other, and in time the largest galaxies of the group will consume the smaller ones. The Milky Way is one of the larger galaxies in our local group, and so it has consumed smaller galaxies in the past. But piecing together the history of these galactic meals is a real challenge.
In 1866 the American astronomer Daniel Kirkwood was studying all the known asteroids, which at the time amounted to several hundred. If you just look at a snapshot of the solar system, there’s nothing that particularly stands out about the asteroids. They appear to have all sorts of random positions and random orbits within the main asteroid belt, which sits halfway between Mars and Jupiter.
To date, a total of 4,884 extrasolar planets have been confirmed in 3,659 systems, with another 8,414 additional candidates awaiting confirmation. In the course of studying these new worlds, astronomers have noted something very interesting about the “rocky” planets. Since Earth is rocky and the only known planet where life can exist, astronomers are naturally curious about this particular type of planet. Interestingly, most of the rocky planets discovered so far have been many times the size and mass of Earth.
It’s almost impossible to comprehend a supernova explosion’s violent, destructive power. An exploding supernova can outshine its host galaxy for a few weeks or even months. That seems almost impossible when considering that a galaxy can contain hundreds of billions of stars. Any planet too close to a supernova would be completely sterilized by all the energy released, its atmosphere would be stripped away, and it may even be shredded into pieces.
On November 16th, 1974, a coded radio message was broadcast from the Arecibo Observatory in Puerto Rico. The message contained information on mathematics, humanity, the Solar System, DNA, and the Observatory itself. The destination for this message was Messier 13 (NGC 6205 or “The Great Hercules Cluster”), a globular star cluster located about 25,000 light-years from Earth in the constellation of Hercules.
If you thought landing a used rocket booster on a barge or a landing pad was crazy idea, take a look at how SpaceX plans to land the big Starship rocket.
Earth has had a long and complex history since its formation roughly 4.5 billion years ago. Initially, it was a molten ball, but eventually, it cooled and became differentiated. The Moon formed from a collision between Earth and a protoplanet named Theia (probably), the oceans formed, and at some point in time, about 4 billion years ago, simple life appeared.
70% of astronauts who spend time on the International Space Station (ISS) experience swelling at the back of their eyes, causing blurriness and impaired eyesight both in space and when they return to Earth. Sometimes, it’s permanent. Understanding the way microgravity affects the eyes, and the human body as a whole is an essential part of preparations for future long-duration spaceflights to the Moon and Mars. In an effort to understand the cause of these eye problems, researchers at the Medical University of South Carolina used MRI scans of twelve ISS astronauts to measure the intracranial venous system (veins that circulate blood to the brain) before and after flight. They’ve determined that there is a strong connection between the swelling of these veins and the onset of eye trouble.
Let’s not sugarcoat it. Exploring the Moon is not for the faint of heart! It’s an airless body, which means there is no atmosphere, the surface temperatures are extreme, and there’s lots of radiation. The low gravity also means you can never really walk on the surface and have to bounce around in a bulky spacesuit until you fall over. And you can bet your bottom dollar people will make a supercut of the footage someday (see below). Then there’s that awful moondust (aka. lunar regolith), which is electrostatically charged and sticks to EVERYTHING!
The James Webb Space Telescope primary mirror is now fully unfolded, which successfully completes the mission’s major deployments. The starboard side of the primary mirror was released into place today, completing a two-week long, complex deployment sequence. The mirror of the most powerful space telescope ever built is now open to prepare to “unfold the Universe.”
Most Universe Today readers are familiar with nebulae. They’re gaseous structures lit up with radiation from nearby stars, and they’re some of nature’s most beautiful forms.

