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An ApJL preprint on archive today “JWST detection of a carbon dioxide dominated gas coma surrounding interstellar object 3I/ATLAS”
Says the coma is CO2 dominated, with enhanced outgassing in the sunward direction, and the presence of H2O, CO, OCS, water ice and dust. The coma CO2/H2O mixing ratio is among the highest ever observed in a comet – the authors discuss why this might be the case depending on its origins.
Water detected and possible large icy grains, ApJL preprint: https://arxiv.org/abs/2508.04675
Good to hear you are continuing to monitor T CrB with your Seestar, Heinz-Bernd. As you say, now is not the time to blink!
So when will the eruption occur ? I am very impatient.
Many thanks.Kwong Man
That will be when sufficient matter has accumulated on the surface of the white dwarf to trigger a thermonuclear runaway. Your guess is as good as mine when that will be.
More nice data, Ian. The changes in eclipse width FWHM should reveal the disc shrinking as it cools.
Ulisse Munari et al. have published a pretty comprehensive analysis of T CrB’s accretion history in this Astronomy & Astrophysics preprint:
https://arxiv.org/abs/2507.23323They point out that its superactive phase from 2015 to 2023 was actually not quite as active as the equivalent phase that preceded the 1946 eruption. They note that the increased accretion since May 2024 is making up for this deficit.
Hello John,
I asked Alexander about polarimetry and he says “my quick research shows that no polarimetric monitoring has been done for X Persei in quite a long time (since 1994), at least not in the published literature.”
If he finds more info, he will get back to me.
Go well!
JeremyA chart and sequence for visual observers is here: https://britastro.org/vss/xchartcat/x-per-277.html
An ApJL preprint on ArXiv today presents events for the probable direct imaging of a lower mass companion of Betelgeuse: https://arxiv.org/abs/2507.15749
There is an interesting paper on ArXiv today that looks at the effect of geomagnetic activity in the re-entry of Starlink satellites, especially during the rising phase of Cycle 25: https://arxiv.org/abs/2505.13752
An MNRAS preprint on ArXiv today considers “Near-Infrared Spectroscopy of the Recurrent Nova M31N 2008-12a” during the 2024 eruption discussed in the thread: https://arxiv.org/abs/2505.10431
More on the Nova Super Remnant (NSR) around RS Oph. This time deep narrowband Condor Array Telescope imagery which have revealed a ∼1.5 degree, ∼ 70 pc-sized NSR in this ApJ preprint on ArXiv: https://arxiv.org/abs/2505.09510
There is an intriguing paper relating to this eclipse that has recently been published and cited on spaceweather.com. Giovanni di Giovanni might be especially interested as it refers to the electrical response of spruce trees in the Dolomites to this eclipse: https://royalsocietypublishing.org/doi/10.1098/rsos.241786
“As the eclipse approached, electrical signals from different trees began to align; their waveforms became more similar in shape and timing. This synchronization peaked during the eclipse and gradually diminished afterward. Older trees started showing electrical changes earlier, in some cases hours before the eclipse began, while younger trees responded later and more weakly.
The researchers interpreted this as a coordinated response to a large-scale environmental event, possibly involving communication or shared signaling pathways. ”
A paper on ArXiv today discusses “Initial Observations of the First BlueBird Spacecraft and a Model of Their Brightness”, https://arxiv.org/abs/2505.05820
“Based on a large set of visual observations, the mean apparent magnitude of BlueBird satellites is 3.44, while the mean of magnitudes adjusted to a uniform distance of 1000 km is 3.84. Near zenith the spacecraft can be as bright as magnitude 0.5. While these spacecraft are bright enough to impact astronomical observations, they can for periods be fainter than the BlueWalker 3 prototype satellite. A model for their brightness shows that design changes since the BlueWalker 3 mission can explain the behavior of BlueBird.”
I hoped they may stick their necks on in the section 4.3 “when will T CrB erupt?”. They observe that “Recent photometric and spectroscopic observations indicate that the system is returning to a high-accretion state. Given this, an eruption may be imminent, even without distinct precursors”. So, as ever, we shall just have to keep on watching as there might be no warning.
An MNRAS preprint on ArXiv today reviews images of the VN since 2017: https://arxiv.org/abs/2505.01760
The paper “Hubble’s Variable Nebula I: Ripples on a Big Screen” describes how they compiled images into a movie which can be viewed here: https://www.youtube.com/watch?v=5QOkzmlSzKI
