Space and astronomy news
Picture the Universe’s ancient beginnings. In the vast darkness, light was emitted from a particular galaxy only 460 million years after the Big Bang. On the way, the light was shifted into the infrared and magnified by a massive gravitational lens before finally reaching the James Webb Space Telescope.
The galaxy is called the Cosmic Gems arc, and it held some surprises for astronomers.
Continue reading “Webb Sees Globular Clusters Forming in the Early Universe”
There’s something poetic about humanity’s attempt to detect other civilizations somewhere in the Milky Way’s expanse. There’s also something futile about it. But we’re not going to stop. There’s little doubt about that.
One group of scientists thinks that we may already have detected technosignatures from a technological civilization’s Dyson Spheres, but the detection is hidden in our vast troves of astronomical data.
Continue reading “Astronomers are on the Hunt for Dyson Spheres”
In July 2022, NASA’s James Webb Space Telescope (JWST) used its NIRCam (Near-Infrared Camera) to capture stunning infrared images of the largest planet in the solar system, Jupiter. Within these striking images, scientists recently discovered a jet stream in the northern latitudes just over Jupiter’s equator and 20-35 kilometers (12-21 miles) above Jupiter’s cloud tops. This jet stream stretches approximately 4,800 kilometers (3,000 miles) with speeds of 515 kilometers per hour (320 miles per hour), more than double the speed of a Category 5 hurricane on Earth.
Continue reading “A New Weather Feature was Hiding in JWST’s Picture of Jupiter”
The James Webb Space Telescope is widely considered to be better than the Hubble Space Telescope. But the JWST doesn’t replace its elder sibling; it’s the Hubble’s successor. The Hubble is nowhere near ready to retire. It’s still a powerful science instrument with lots to contribute. Comparing images of the same object, NGC 5068, from both telescopes illustrates each one’s value and how they can work together.
Continue reading “Compare Images of a Galaxy Seen by Both Hubble and JWST”
The JWST is grabbing headlines and eyeballs as its mission gains momentum. The telescope recently imaged M74 (NGC 628) with its Mid-Infrared Instrument (MIRI.) Judy Schmidt, a well-known amateur astronomy image processor, has worked on the image to bring out more detail.
Continue reading “Here’s M74 Like You’ve Never Seen it Before, Thanks to Judy Schmidt and JWST”
Searching for Dyson spheres, rings, or swarms remains a preoccupation of many astronomers. If there are any out there, they will eventually be found, and the person or research team to do so will go down in history for making one of the most momentous discoveries in the history of humanity. If you’re interested in claiming that accolade for yourself, an excellent place to look may be around white dwarfs. At least, that’s the theory put forward in a new paper by Benjamin Zuckerman, a now-retired professor of astrophysics at UCLA.
Continue reading “If There are Dyson Spheres Around White Dwarfs, We Should be Able to Detect Them”
A lot of the threats humanity faces come from ourselves. If we were listing them, we’d include tribalism, greed, and the fact that we’re evolved primates, and our brains have a lot in common with animal brains. Our animalistic brains subject us to many of the same destructive emotions and impulses that animals are subject to. We wage war and become embroiled in intergenerational conflicts. There are genocides, pogroms, doomed boatloads of migrants, and horrible mashups of all three.
Isn’t humanity fun?
But not all of the threats we face are as intractable as our internal ones. Some threats are external, and we can leverage our technologies and our knowledge of nature in the struggle against them. Case in point: asteroids.
Continue reading “NASA has Approved a Space Telescope That Will Scan the Skies for Dangerous Near-Earth Asteroids”
The oldest stars in the Universe are cloaked in darkness. Their redshift is so high, we can only wonder about them. The James Webb Space Telescope will be our most effective telescope for observing the very early Universe, and should observe out to z = 15. But even it has limitations.
To observe the Universe’s very first stars, we need a bigger telescope. The Ultimately Large Telescope.
Continue reading “What Telescope Will Be Needed to See the First Stars in the Universe? The Ultimately Large Telescope”
NASA’s Spitzer Space Telescope has reached the end of its life. Its mission was to study objects in the infrared, and it excelled at that since it was launched in 2003. But every mission has an end, and on January 30th 2020, Spitzer shut down.
Continue reading “Good-bye Spitzer. We’ll Miss You But We Won’t Forget You.”
The Cassini spacecraft ended its mission on September 15th, 2017, when it crashed into Saturn’s atmosphere, thus preventing any possible contamination of the system’s moons. Nevertheless, the wealth of data the probe collected during the thirteen years it spent orbiting Saturn (of the gas giant, its rings, and its many moons) continues to be analyzed by scientists – with amazing results!
Case in point, the Cassini team recently released a series of colorful images that show what Titan looks like in infrared. The images were constructing using 13 years of data that was accumulated by the spacecraft’s Visual and Infrared Mapping Spectrometer (VIMS) instrument. These images represent some of the clearest, most seamless-looking global views of the icy moon’s surface produced so far.
Infrared images provide a unique opportunity when studying Titan, which is difficult to observe in the visible spectrum because of its dense and hazy atmosphere. This is primarily the result of small particles called aerosols in Titan’s upper atmosphere, which strongly scatter visible light. However, where the scattering and absorption of light is much weaker, this allows for infrared “windows” that make it possible to catch glimpses of Titan’s surface.
It is because of this that the VIMS was so valuable, allowing scientists to provide clear images of Titan’s surface. This latest collection of images are especially unique because of the smoothness and clarity they offer. In previous infrared images captured by the Cassini spacecraft of Titan (see below), there were great variations in imaging resolution and lighting conditions, which resulted in obvious seams between different areas of the surface.
This is due to the fact that the VIMS obtained data over many different flybys with different observing geometries and atmospheric conditions. As a result, very prominent seams appear in mosaic images that are quite difficult to remove. But, through laborious and detailed analyses of the data, along with time consuming hand processing of the mosaics, Cassini’s imaging team was able to mostly remove the seams.
The process used to reduce the prominence of seams is known as the “band-ratio” technique. This process involves combining three color channels (red, green and blue), using a ratio between the brightness of Titan’s surface at two different wavelengths. The technique also emphasizes subtle spectral variations in the materials on Titan’s surface, as evidenced by the bright patches of brown, blue and purple (which may be evidence of different compositions).
In addition to offering the clearest and most-seamless glimpse of Titan yet, these unique images also highlight the moon’s complex geography and composition. They also showcase the power of the VIMS instrument, which has paved the way for future infrared instruments that could capture images of Titan at much higher resolution and reveal features that Cassini was not able to see.
In the coming years, NASA hopes to send additional missions to Titan to explore its surface and methane lakes for signs of biosignatures. An infrared instrument, which can see through Titan’s dense atmosphere, provide high-resolution images of the surface and help determine its composition, will prove very useful in this regard!
Further Reading: NASA