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You’d think that something happening billions of light-years away wouldn’t affect Earth, right? Well, in 2002, a burst of gamma rays lasting 800 seconds actually impacted our planet. They came from a powerful and very distant supernova explosion. Its gamma-ray bombardment disturbed our planet’s ionosphere and activated lightning detectors in India.

This particular gamma-ray burst (GRB) occurred in a galaxy almost 2 billion light-years away (and took two billion years to reach us). Not only did ground-based detectors record the bombardment, but satellites sensitive to high-energy outbursts “saw” it, too. That included the European Space Agency’s International Gamma-Ray Astrophysics Laboratory (INTEGRAL) mission. It typically records gamma-ray bursts on a daily basis, but this one—named GRB 221009A—outshone all the rest.

GRBs this strong happen (on average) about once every 10,000 years, so this was one that caught everyone’s attention. “It was probably the brightest gamma-ray burst we have ever detected,” says Mirko Piersanti, University of L’Aquila, Italy, and lead author of a paper analyzing the event.

How The Gamma-ray Burst Affected the Ionosphere

Most of the time, radiation from the Sun bombards our planet. That’s often strong enough to affect the ionosphere. That’s an atmospheric layer that bristles with electrically charged gases called plasma. It stretches from around 50 km to 950 km in altitude above the surface. There’s a “top-side ionosphere” (which lies above 350 km) and a “bottom-side ionosphere”) which lies below that. Scientists are pretty familiar with how the Sun treats this region of the atmosphere, particularly during periods of heavy solar activity.

GRB 221009A: looking back through time at a gamma-ray-burst. Courtesy ESA
GRB 221009A: looking back through time at a gamma-ray-burst. Courtesy ESA

This GRB blast triggered instruments generally reserved for studying the immense explosions in the Sun’s atmosphere known as solar flares. “Notably, this disturbance impacted the very lowest layers of Earth’s ionosphere, situated just tens of kilometers above our planet’s surface, leaving an imprint comparable to that of a major solar flare,” says Laura Hayes, research fellow and solar physicist at ESA. That imprint basically was an increase in ionization in the bottom-side ionosphere. It left an imprint in low-frequency radio signals that move between Earth’s surface and the lowest levels of the ionosphere. “Essentially, we can say that the ionosphere ‘moved’ down to lower altitudes, and we detected this in how the radio waves bounce along the ionosphere,” explained Laura.

Gamma Ray Bursts in the Data

Past GRBs bothered the bottom-side ionosphere but didn’t always disturb the topside. Scientists just assumed that by the time it reached Earth, the blast from a GRB didn’t have the “oomph” to change that part of the ionosphere. GRB 221009A proved that idea wrong. Thanks to data from the orbiting China Seismo-Electromagnetic Satellite (CSES), scientists saw a strong disturbance in the upper ionosphere. It created a strong electric field variation and was the first time scientists saw this connected to a GRB. The result is the first-ever top-side ionospheric measurement of electric field variations triggered by a gamma-ray outburst at cosmic distances.

INTEGRAL and other spacecraft continually record GRBs from around the Universe. Have they all affected our ionosphere in some way? Is there a way to find out? Now that scientists know what ionospheric effects to look for, they can search the data to find answers. Data from INTEGRAL, and CSES will be particularly useful. They should be able to correlate it with other GRBs seen since 2018. That’s when CSES was launched.

Evidence of ionospheric disturbances from GRBs goes back as far as 1988. That’s when the effects of a 1983 gamma-ray burst were first reported. Scientists now have an array of ground-based and space-based detectors—such as Swift, Fermi, MAXI, AGILE, INTEGRAL, and CSES—gave strong detections of the emissions from GRB221009A.

Implications for Future GRB Effects on Earth

This kind of disturbance
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Experimental Radar Technique Reveals the Composition of Titan’s Seas

Cassini Titan bistatic schematic 1024x523 1

The Cassini-Huygens mission to Saturn generated so much data that giving it a definitive value is impossible. It’s sufficient to say that the amount is vast and that multiple scientific instruments generated it. One of those instruments was a radar designed to see through Titan’s thick atmosphere and catch a scientific glimpse of the moon’s extraordinary surface.

Scientists are still making new discoveries with all this data.

Though Saturn has almost 150 known moons, Titan attracts almost all of the scientific attention. It’s Saturn’s largest moon and the Solar System’s second largest. But Titan’s surface is what makes it stand out. It’s the only object in the Solar System besides Earth with surface liquids.

Cassini’s radar instrument had two basic modes: active and passive. In active mode, it bounced radio waves off surfaces and measured what was reflected back. In passive mode, it measured waves emitted by Saturn and its moons. Both of these modes are called static modes.

But Cassini had a third mode called bistatic mode that saw more limited use. It was experimental and used its Radio Science Subsystem (RSS) to bounce signals off of Titan’s surface. Instead of travelling back to sensors on the spacecraft, the signals were reflected back to Earth, where they were received at one of NASA’s Deep Space Network (DNS) stations. Critically, after bouncing off of Titan’s surface, the signal was split into two, hence the name bistatic.

A team of researchers has used Cassini’s bistatic data to learn more about Titan’s hydrocarbon seas. Their work, “Surface properties of the seas of Titan as revealed by Cassini mission bistatic radar experiments,” has been published in Nature Communications. Valerio Poggiali, a research associate at the Cornell Center for Astrophysics and Planetary Science, is the lead author.

This schematic shows how Cassini's bistatic radar experiment worked. The orbiter used its Radio Science Subsystem to send signals to Titan's surface. The signals then reflected off of Titan to Earth, where they were received by either the DNS receiver at Canberra, Goldstone, or Madrid. The signals are either Right Circularly Polarized (RCP) or Left Circularly Polarized (LCP.) Image Credit: Poggiali et al. 2024.
This schematic shows how Cassini’s bistatic radar experiment worked. The orbiter used its Radio Science Subsystem to send signals to Titan’s surface. The signals then reflected off Titan to Earth, where they were received by one of the DNS receivers at Canberra, Goldstone, or Madrid. The signals are either Right Circularly Polarized (RCP) or Left Circularly Polarized (LCP). Image Credit: Poggiali et al. 2024.

The signals that reach the DNS are polarized, which reveals more information about the hydrocarbon seas on Titan. While Cassini’s radar instrument revealed how deep the seas are, the bistatic radar data tells researchers about both their compositions and surface textures.

This image of the hydrocarbon seas on Titan is well-known and was radar-imaged by Cassini. That radar data told us how deep the seas are. New bistatic radar data can reveal more about the composition and surface texture of the seas. Image Credit: [JPL-CALTECH/NASA, ASI, USGS]
This image of the hydrocarbon seas on Titan is well-known and was radar-imaged by Cassini. That radar data told us how deep the seas are. New bistatic radar data can reveal more about the composition and surface texture of the seas. Image Credit: [JPL-CALTECH/NASA, ASI, USGS]

“The main difference,” Poggiali said, “is that the bistatic information is
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Webb Measures the Weather on a Tidally Locked Exoplanet

Webb Atmosphere Graphic 1024x663 1

Exploring exoplanet atmospheres in more detail was one task that planetary scientists anticipated during the long wait while the James Webb Space Telescope (JWST) was in development. Now, their patience is finally paying off. News about discoveries of exoplanet atmosphere using data from JWST seems to be coming from one research group or another almost every week, and this week is no exception. A paper published in Nature by authors from a few dozen institutions describes the atmospheric differences between the “morning” and “evening” sides of a tidally locked planet for the first time.

First, let’s clarify what the “morning” and “evening” sides mean. Tidally locked planets don’t spin, so one hemisphere constantly faces the planet’s star. As such, there is always a part of the planet where it appears to be “morning,” with the star barely peaking over the horizon. Alternatively, there’s a part of the planet where it seems to be “evening,” where the star is again just barely peaking over the horizon, but it would appear to be setting. 

Typically, on Earth, we would think of the morning side as the star peaking over the eastern side, whereas the evening side would see the star setting into the western sky. However, exoplanets sometimes rotate in the opposite direction from planets in our solar system, so that mental model doesn’t always work for them.

Webb Atmosphere Graphic 1024x663 2
The JWST light curve for WASP-34b, clearly showing the dip in the star’s brightness as the planet passes in front of it.
Credit – NASA / ESA / CSA / R. Crawford (STScI)

It’s also important not to confuse the “morning” and “evening” sides with the “day” and “night” sides of the planet. On the day side, the full force of the star affects the planet, but on the night side, the star is never seen at all. The temperature differences on such a planet are massive, and cause much more extreme weather than anything we have experience with in our solar system.

That is the case for WASP-39b, one of the most studied exoplanets. It is a “hot Jupiter” and is roughly 1.3 times the size of the largest planet in our solar system, though it only masses in at about the same size as Saturn. It’s 700 light years away and is tidally locked to its star.

Exoplanet hunters have intently studied this exoplanet since its discovery in 2011. It was the target of JWST’s first exoplanet research when it began science operations. Since then, they’ve made several interesting discoveries, and the Nature paper describes a new one—that the “morning” side of WASP-39b is a few hundred degrees cooler than its “evening” side.

Fraser talks exoplanet atmosphere with expert Dr. Joanna Barstow.

This temperature discrepancy is likely due to atmospheric conditions on the planet itself. The paper’s authors believe there is an extremely strong wind on the planet that runs from day to night at thousands of miles an hour. The wind rotates from the day side through the evening side to the night side, then through the morning side back to the day side.

So, essentially, the morning side receives “air” that has been cooled while traveling through the planet’s night side. However, that air is still a blistering 600 C (1,150 F). The temperature on the evening side, though, is hotter at 800 C (1,450 F), much hotter than any conditions found on any planet in our solar system.

Detecting such a temperature difference on an exoplanet hundred of light years away is an impressive technical feat, and the study’s lead author, Néstor Espinoza, credits JWST’s capabilities for enabling it. The telescope watched the planet both while it was traversing in front of its star, but also while it was next to it and emitting its own, admittedly much fainter, light. 

JWST found methane in a different exoplanet atmosphere, as Fraser describes in this video.

They were differentiating between the starlight filtered through the atmosphere of the planet and when there was no filtered starlight coming through allowed the researchers to make temperature estimates. JWST is so sensitive they were also able to split the data into semi-circles to differentiate the”
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Review: Deuter Aircontact Ultra 50+5 and 45+5 SL Backpacks

Tet19 047 Me on Teton Crest Trail copy cropped 36

Ultralight Backpacks
Deuter Aircontact Ultra 50+5

$250, 55L/3,356 c.i., 2 lbs. 15 oz./1.33kg
Deuter Aircontact Ultra 45+5 SL

$250, 50L/3,051 c.i., 2 lbs. 11 oz./1.21kg

One adjustable size in both models

Aircontact Ultra 50+5:

Aircontact Ultra 45+5 SL:

To put Deuter’s updated-for-2024 Aircontact Ultra 50+5 ultralight backpack through the paces, I took it on a pair of quite rugged but also quite different backpacking trips this spring: a three-day hike through southern Utah’s Owl and Fish canyons with a max weight of about 30 pounds in the pack, and six days and about 60 miles backpacking the Grand Canyon’s Gems Route, repeatedly carrying extra water—and starting out with more than 40 pounds inside, including over 10 pounds of water and 11 pounds of food. As I expected, those trips revealed much about the Aircontact Ultra backpacks and why they might appeal to lightweight and ultralight backpackers.

First, I must acknowledge that 40 pounds significantly exceeds Deuter’s recommended max weight for these packs: I knew that but wanted to gauge the Aircontact Ultra’s comfort by exceeding its weight capacity and then seeing when it starts feeling comfortable as my pack weight decreased each day—as I sometimes do with packs in this weight class because, almost inevitably, many backpackers overload ultralight packs at the outset of a trip, or at various points during a long-distance hike, accepting a day or more of compromised comfort for the benefit of having a pack that’s lighter and will be adequately comfortable for most of the trip. I’ve done that countless times.

Tet19 047 Me on Teton Crest Trail copy cropped 37
Hi, I’m Michael Lanza, creator of The Big Outside. Click here to sign up for my FREE email newsletter. Join The Big Outside to get full access to all of my blog’s stories. Click here for my e-books to classic backpacking trips. Click here to learn how I can help you plan your next trip.

The Deuter Aircontact Ultra 50+5 harness.
” data-image-caption=”The Deuter Aircontact Ultra 50+5 harness.
” data-medium-file=”″ data-large-file=”″ tabindex=”0″ role=”button” src=”×1024.jpg?resize=683%2C1024&ssl=1″ alt=”The Deuter Aircontact Ultra 50+5 harness.” class=”wp-image-63988″ style=”aspect-ratio:0.6671875;width:488px;height:auto” srcset=” 683w, 200w, 768w, 150w, 800w” sizes=”(max-width: 683px) 100vw, 683px” data-recalc-dims=”1″ />The Deuter Aircontact Ultra 50+5 harness.

In the Grand Canyon, having more than 40 pounds/18.1 kilos in the Aircontact Ultra 50+5 was certainly not “comfortable.” But nor was it all that bad. On that first day, we backpacked about six miles of rough dirt road just to reach the South Bass Trailhead, and then descended the often steep, loose, and rugged South Bass Trail for some 3,400 feet before
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