CHANCE OF STRONG FLARES: Don't be surprised if there's an X-flare today. Two sunspots (4232 and 4236) have unstable delta-class magnetic fields, and both are facing Earth. Shortwave radio blackouts and geoeffective CMEs are likely if an explosion occurs. Solar flare alerts: SMS Text.
COMET 3I/ATLAS HAS REACHED MARS: Interstellar Comet 3I/ATLAS is approaching Mars for a close encounter on October 3rd. The Mars Fleet is ready. "We're about to get our best-ever look at an interstellar comet," says physicist T. Marshall Eubanks from Space Initiatives Inc, who is helping coordinate the international spacecraft teams.
As many as 6 spacecraft could get a close-up view: NASA’s MAVEN and Mars Reconnaissance Orbiter, ESA's Mars Express and ExoMars Trace Gas Orbiter, the UAE's Hope probe, and China's Tianwen-1.
Because 3I/ATLAS is now invisible from Earth as it swings behind the sun (a blackout that will last until December) Martian spacecraft may provide the only high-quality spectra and images of the comet at its brightest. "The fleet at Mars could deliver the definitive dataset," write Eubanks and colleagues, who authored a new study urging space agencies to seize this opportunity.
When the comet passes Mars on Oct. 3rd, it will be almost bright enough to see with human eyes--about magnitude +6.7, according to Eubanks. If only humans were there to see it. Spacecraft will have to do all the work. The comet will be 0.195 AU (29 million km) from the Red Planet, giving the orbiting fleet a ringside seat.
Of all the cameras involved, Mars Reconnaissance Orbiter's HiRISE will deliver the sharpest images: 29 km per pixel. HiRISE should resolve the comet's atmosphere (coma) with more than 850 pixels. Researchers will be on the edge of their seats to see if the camera can also glimpse the nucleus hidden within the gas cloud. Photographing the core could put to rest internet rumors that it is "alien tech."
For Eubanks, getting the maximum amount of data is a labor of love. "I have worked on this very intensively since July," says Eubanks. "As my wife would tell you, we have no funding source for this."
Mars is getting big in the window. Let the observing begin!
THE GEOMAGNETIC STORM CONTINUES: Earth's magnetic field has been vibrating for 4 consecutive days--a remarkably long-lasting geomagnetic storm. Last night, Valentin Grigore photographed the light show from Tromso, Norway:
"This outburst appeared on Oct. 1st," says Grigore. "I am leading a group of 17 Romanians to Norway to observe the auroras. I never imagined we would be able to see such a spectacular aurora storm so many nights in a row."
Thank the Russell-McPherron effect. During weeks around equinoxes, the magnetic field of the sun can connect itself to the magnetic field of the Earth. Under these circumstances, even slight gusts of solar wind ignite auroras.
Current solar wind speeds are anything but slight, with gusts topping 600 km/s. NOAA forecasters say G2-class geomagnetic storms are likely on Oct. 2nd. Five days in a row, anyone? Aurora alerts: SMS Text.
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CONSTELLATION CAT NIGHT LIGHT: It's the most far-out feline night light ever--the Constellation Cat Crystal Ball. On April 23, 2025, the students of Earth to Sky Calculus launched it to the stratosphere onboard a giant helium balloon.
You can have it for $139.95. Outlined by stars in the style of an astronomical constellation, the laser-etched cat comes with an LED stand that produces a soothing glow for your bedside table. Also included: A unique greeting card shows the crystal ball in flight and tells the story of its journey to the edge of space.
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