A Solo Brown Dwarf Found With Auroras

This artist concept portrays the brown dwarf W1935, which is located 47 light-years from Earth. Astronomers using NASA’s James Webb Space Telescope found infrared emission from methane coming from W1935, generating an aurora, a very unexpected discovery. Credit: NASA, ESA, CSA, Leah Hustak (STScI)

Astronomers have used JWST to find a brown dwarf with polar auroras like the Earth, or Jupiter. This is surprising because the brown dwarf, dubbed W1935, is a free-floating object, meaning it isn’t part of another star system. Therefore, there’s no solar wind available to generate any Northern Lights. Instead, the auroras are seemingly generated from methane emissions in the planet’s atmosphere, interacting with the interstellar plasma. Another theory is that it perhaps has an active but unseen moon contributing to the emissions.

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Solar Storms Could Cause Mayhem to Trains

Solar storm. Image credit: NASA
Solar storm. Image credit: NASA

The rail service here in the UK is often the brunt of jokes. If it’s not the wrong type of rain, or the leaves are laying on the tracks the wrong way then it’s some other seemingly ludicrous reason that the trains are delayed, or even cancelled. A recent study by scientists at the University of Lancaster suggest that even the solar wind might cause train signals to be incorrectly triggered with potentially disastrous consequences.

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NASA’s MAVEN Witnessed Auroras as Multiple Solar Storms Crashed into Mars

Artist’s illustration of NASA’s MAVEN spacecraft orbiting Mars. (Credit: NASA)

After orbiting Mars for eight long years, NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft observed an extraordinary duo of auroras around the Red Planet that resulted from solar storms emanating from the Sun only a few days earlier on August 27. This observation is extraordinary since Mars lacks a global magnetic field so the solar flares must have been very powerful for MAVEN to detect them.

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Jupiter’s Atmosphere is Surprisingly Hot

Temperature measurements of Jupiter's upper atmosphere. Credit: James O’Donoghue

Jupiter is a big planet, but it’s still a planet. That means it doesn’t heat itself through fancy mechanisms like nuclear fusion. Its interior is heated through its own weight, squeezing the interior through hydrostatic equilibrium, and its surface is heated mostly by the Sun. Since Jupiter only gets about 4% of the light per square meter that Earth gets, you’d expect its upper atmosphere to be pretty cold. Traditional models estimate it should be about -70 degrees Celsius. But recent measurements show the upper atmosphere is over 400 degrees Celsius, and in the polar regions as much as 700 degrees Celsius. In the words of Ruby Rhod from the movie The Fifth Element, “It’s Hot Hot Hot!”

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A New Map Shows how Solar Winds Rain Down Everywhere on Mars

In a joint effort between NASA’s MAVEN spacecraft and the United Arab Emirates’ Emirates Mars mission (EMM), scientists have observed an uncommonly chaotic interaction between the solar wind and Mars’ upper atmosphere, creating a unique ultraviolet aurora. The phenomenon represents an unusual occurrence in Martian space weather, and scientists are excited to take advantage of future collaborations between spacecraft to keep an eye out for repeat events.

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Webb Telescope Sees Jupiter and Its Auroras in a New Light

JWST view of Jupiter
The James Webb Space Telescope's NIRCam imager produced this composite image of the Jupiter system using orange and cyan filters. The image shows Jupiter's auroras as bright rims at the poles. The planet's rings and two of its moons, Amalthea and Adrastea, are also visible. Credit: NASA, ESA, CSA, Jupiter ERS Team; image processing by Ricardo Hueso (UPV/EHU) and Judy Schmidt.

NASA’s James Webb Space Telescope is designed to probe the farthest frontiers of the universe, but newly released images of Jupiter prove that the observatory can also bring fresh perspectives to more familiar celestial sights.

The infrared images reveal Jupiter’s polar auroras and its faint rings as well as two of its moons — plus some galaxies in the far background. The planet’s Great Red Spot is there as well, but because it’s seen through three of JWST’s specialized filters, it looks white rather than red.

JWST’s new perspective should give scientists a better sense of how the complex Jupiter system is put together.

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Chinese Astronomers Recorded Earliest Account of Aurora

How dating an ancient text revealed one of the oldest observations of aurora known.

It’s one of the greatest sky spectacles you can witness. Along with a total solar eclipse and a major meteor storm, I’d put a fine aurora display up there as one of the the most amazing things you can see in the night sky. And we’re not talking about the dull green glow that folks in the ‘lower 48’ see to the north and dismiss, but the glorious silent streamers of auroral curtains that can light up the entire sky.

Now, a recent study, entitled A Candidate Auroral Report in the Bamboo Annals Indicating a Possible Extreme Space Weather Event in the 10th Century BCE may have pinpointed one of the earliest accounts on ancient aurorae. In the study, University of Pennsylvania and Nagoya University researchers culled through the legendary chronicle known as the Bamboo Annals (also sometimes referred to as Zhushu Jinian) penned around the 4th century BCE. Chinese texts are some of the best documented sources of sky phenomena stretching back over the millennia, to include accounts of naked eye sunspots, supernovae and meteor outbursts.

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Here’s the View From Sweden During the Recent Solar Storm

Aurora seen in Sweden, October 12, 2021. Credit: All-sky camera, Kiruna Atmospheric and Geophysical Observatory (KAGO) within the Swedish Institute of Space Physics (IRF).

Vivid green and purple aurora swirled and danced across the entire night sky in Sweden recently. The nighttime light show was captured by an all-sky camera in Kiruna, Sweden, which is part of the European Space Agency’s (ESA) Space Weather Service Network.

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Ions Surf Through Jupiter’s Magnetic Field, Triggering its Auroras

Auroras come in many shapes and sizes.  Jupiter is well known for its spectacular complement of bright polar lights, which also have the distinction of appearing in the X-ray band.  These auroras are also extreme power sources, emitting almost a gigawatt of energy in a few minutes. But what exactly causes them has been a mystery for the last 40 years.  Now, a team used data from a combination of satellites to identify what is causing these powerful emissions.  The answer appears to be charged ions surfing on a kind of wave.

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Uranus X-Rays are Probably Reflected Sunlight, but There Could be Another Source as Well

X-rays offer a unique insight into the astronomical world.  Invisible to the naked eye, most commonly they are thought of as the semi-dangerous source of medical scans.  However, X-ray observatories, like the Chandra X-ray Observatory are capable of seeing astronomical features that no other telescope can.  Recently scientists found some of those X-rays coming from a relatively unexpected source – Uranus.

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