A striking new image from the James Webb Space Telescope shows a rare object called an Einstein ring. This shows what appears to be a ring-shaped object in the sky, but is actually created by two separate galaxies and the epic forces of gravity.
There’s a useful astronomical phenomenon called gravitational lensing, in which a large object like a galaxy or a cluster of galaxies has so much mass that it actually bends spacetime. If a massive object sits in front of a more distant object, as seen from Earth, the massive object can act like a magnifying glass, letting us see the very distant object in more detail than would normally be possible. This is a relatively common finding in astronomical images, and is one way that scientists are able to study extremely distant galaxies.
Most often, these lensed objects appear curved or distorted by the gravitational forces acting on spacetime. But occasionally, the objects line up in such a way that the distant object appears as an almost perfect circle: this is then called an Einstein ring.
“When the lensed object and the lensing object line up just so, the result is the distinctive Einstein ring shape, which appears as a full circle (as seen here) or a partial circle of light around the lensing object, depending on the precision of the alignment,” Webb scientists explain. “Objects like these are the ideal laboratory in which to research galaxies too faint and distant to otherwise see.”
The galaxy which is close to us and is seen the center of this image is an elliptical galaxy (meaning it is smooth with a bright core) that is part of a cluster called SMACSJ0028.2-7537, while the more distant background galaxy that is stretched into the ring shape is a spiral galaxy (like our Milky Way). Even though this galaxy has been tugged into what looks like a circle shape, you can still see the hints of its spiral arms at the top and bottom of the image.
The image was created using data from both James Webb’s NIRCam instrument and also the Hubble Space Telescope’s Wide Field Camera 3 and the Advanced Camera for Surveys instruments, showing how effective these two telescopes can be when they work together.
After 13 suborbital test flights and more than $15 billion in development costs, SpaceX's Starship has finally reached orbit. The 407-foot megarocket, the most powerful ever built, lifted off from Starbase, Texas, on Monday and delivered its first real payload on it's 14th attempt. The celebration came with an asterisk, though, since SpaceX had to cut the planned 10-hour mission to roughly three hours.
https://twitter.com/SpaceX/status/2104601695711904180
SpaceX is finally ready to give Starship its biggest test yet. The company says the massive rocket's 14th test flight is scheduled for September 22, when it will attempt to put the upper stage into Earth orbit for the first time. The launch is currently pending regulatory approval, with a 75-minute window opening at 7:15 a.m. CT.
Starship has 26 Starlink satellites to deliver
For decades, humanity has looked up at the Moon and wondered what it would be like to live on it. Think sprawling cities, factories, research centers, and permanent human settlements. Unfortunately, there is one fairly fundamental problem with that vision.
A new study published in Frontiers in Space Technologies argues that even the Moon's potentially enormous reserves of frozen water may be nowhere near enough to support city-sized populations sustainably. Researchers Martin Elvis and Jonathan McDowell estimate that the permanently shadowed regions near the lunar poles could contain roughly one billion tons of water. It sounds like an extraordinary amount until you put a million thirsty humans next to it.