Astronomers are on the Hunt for Dyson Spheres

Artist's impression of a Dyson Sphere. The construction of such a massive engineering structure would create a technosignature that could be detected by humanity. Credit: SentientDevelopments.com/Eburacum45
Artist's impression of a Dyson Sphere. The construction of such a massive engineering structure would create a technosignature that could be detected by humanity. Credit: SentientDevelopments.com/Eburacum45

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.

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A New Weather Feature was Hiding in JWST’s Picture of Jupiter

Image of Jupiter taken by NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) in July 2022 displays striking features of the largest planet in the solar system in infrared light, with brightness indicating high altitudes. One of these features is a jet stream within the large bright band just above Jupiter’s equator, which was the focus of this study. (Credit: NASA, ESA, CSA, STScI, R. Hueso (University of the Basque Country), I. de Pater (University of California, Berkeley), T. Fouchet (Observatory of Paris), L. Fletcher (University of Leicester), M. Wong (University of California, Berkeley), J. DePasquale (STScI))

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.

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Compare Images of a Galaxy Seen by Both Hubble and JWST

NGC 5068 is a barred spiral galaxy about 20 million light-years away. The Hubble captured this image of NGC 5068 in ultraviolet, visible, and near-infrared light. Image Credits: NASA, ESA, R. Chandar (University of Toledo), and J. Lee (Space Telescope Science Institute); Processing: Gladys Kober (NASA/Catholic University of America)

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.

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Here’s M74 Like You’ve Never Seen it Before, Thanks to Judy Schmidt and JWST

The JWST recently imaged NGC628, also knows an M74. Well-known astronomy image processor Judy Schmidt reworked the image to show more detail. Image Credit: NASA/ESA/CSA/STSCI/JUDY SCHMIDT CC BY 2.0

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.

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If There are Dyson Spheres Around White Dwarfs, We Should be Able to Detect Them

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.  

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NASA has Approved a Space Telescope That Will Scan the Skies for Dangerous Near-Earth Asteroids

An artist's illustration of the NEO Surveyor, a space telescope designed to detect and catalogue NEOs. Image Credit: NASA/JPL

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.

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What Telescope Will Be Needed to See the First Stars in the Universe? The Ultimately Large Telescope

New results from the NASA/ESA Hubble Space Telescope suggest the formation of the first stars and galaxies in the early Universe took place sooner than previously thought. A European team of astronomers have found no evidence of the first generation of stars, known as Population III stars, when the Universe was less than one billion years old. This artist’s impression presents the early Universe. Image Credit: ESA/Hubble, M. Kornmesser.

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.

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Good-bye Spitzer. We’ll Miss You But We Won’t Forget You.

An image from each year of Spitzer's operation. Image Credit: NASA/JPL

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.

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Titan Looks Cool in Infrared

Infrared images of Saturn's moon Titan, captured by Cassini's the Visual and Infrared Mapping Spectrometer (VIMS) instrument. Credit: NASA/JPL-Caltech/Stéphane Le Mouélic, University of Nantes, Virginia Pasek, University of Arizona

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.

Comparison between how Titan appears in visible light (center), and in infrared. Credit: NASA/JPL-Caltech/Stéphane Le Mouélic, University of Nantes, Virginia Pasek, University of Arizona

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).

The three mosaics shown here were composed with data from Cassini’s Visual and Infrared Mapping Spectrometer (VIMS) taken during the three flybys of Titan. Credit: NASA/JPL/University of Arizona

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

NASA Discovers 72 New Asteroids Near Earth

Artist's impression of a Near-Earth Asteroid passing by Earth. Credit: ESA

Of the more than 600,000 known asteroids in our Solar System, almost 10 000 are known as Near-Earth Objects (NEOs). These are asteroids or comets whose orbits bring them close to Earth’s, and which could potentially collide with us at some point in the future. As such, monitoring these objects is a vital part of NASA’s ongoing efforts in space. One such mission is NASA’s Near-Earth Object Wide-field Survey Explorer (NEOWISE), which has been active since December 2013.

And now, after two years of study, the information gathered by the mission is being released to the public. This included, most recently, NEOWISE’s second year of survey data, which accounted for 72 previously unknown objects that orbit near to our planet. Of these, eight were classified as potentially hazardous asteroids (PHAs), based on their size and how closely their orbits approach Earth.

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