Today in my Astro Sci-Comm class we tried something new: we watched clips of 4 astronomers, & discussed the wildly different speaking/presenting styles. Of course I chose these to be VERY different in style. Only 1 was a chaotic train wreck (spoiler, it was me from +10yrs ago) #astrodon#academicchatter#astronomy
"Next steps for the project could include follow-up observations by the James Webb Space Telescope, which would deliver important insights into the planet's surface mineralogy, and the potential for an atmosphere."
#solarstorm
I predict the next big cult of the Sun will be started by radio astronomers, whose life has become way too much dependent on the cycles of solar activity these days.
Human sacrifices of post-docs and phd will be the next step I guess. 😬 #astrodon#astronomy
Hier ist ein Vergleich von gestackten Bildern, die ich von M101 mit meinem #EvoGuide 50ED und #SkyWatcher Az-GTi aufgenommen habe.
Das erste Bild wurde letztes Jahr im Juli mit einer ASI224MC aufgenommen. Es ist ein Stack von 2550 Bildern mit jeweils 3s Belichtung, insgesamt 7650s.
Obwohl es letzte Nacht windig war, konnte ich 50 Bilder mit 120s Belichtungszeit aufnehmen (6000s Gesamtbelichtungszeit). Diesmal wurde eine ASI533MC-Pro verwendet.
1/2 I still struggle getting used to the fact that the smallest mirrors of the Extremely Large Telescope are similar in size to the primary mirrors of many current telescopes!
The M5 – the fifth mirror in the optical path – has reached a key milestone: its blank, the piece that will be later polished, has been finalised.
Limbach+ on “Occurrence Rates of Exosatellites Orbiting 3-30MJup Hosts from 44 Spitzer Light Curves” with some very intriguing measurements that are suggesting exomoon eclipses around free floating low mass objects and occurrence rates of ~0.6 for short period terrestrial exosatellites 🔭🪐 #astrodonhttps://arxiv.org/abs/2405.08116
Awesome work by F.Ubertosi (University of Bologna) using from LOFAR to VLBI radio observations (together with Chandra's X-ray obs.) to probe the feedback history of central galaxy in cluster RBS 797
covering in radio from ~100kpc to ~10pc in scales (!) this study support the idea that the dynamics of this system is explained by a binary supermassive black hole merger
Das sind die Nordamerika (links) und Pelikan Nebel (rechts) im Sternbild Cygnus. Getrennt werden die beiden Emissionsnebel durch die so genannte "Great Wall", eine gigantische Staubwolke.
Die Aufnahme ist als HOO Variante entwickelt, also als Falschfarbendarstellung, um die Verteilung der verschiedenen Gasgebiete zu zeigen.
What did we do & why is this interesting? Deep technical dive ahead!
We learn about accreting #BlackHoles studying their spectra & short-term (~millisecond) variability, called timing. However, individually, both approaches leave us with a lot of puzzles - so we try to combine them in spectral-timing.
In the past, we could only do so above 3 keV using RXTE (and a bit using XMM, but not quiet that well - for this kind of study, one needs many short observations at different times and this is not the XMM observing strategy). Utilizing NICER, we can push down to 0.5 keV and thus finally, finally, probe details of the disk variability in different spectral states of the source!
Generally and kinda unsurprisingly, things are a lot more complex at low energies!
People have shown in the past (and M. Böck & I have really driven home for Cyg X-1 in 2011 & 2014) that power spectra (ways to measure contributions to overall variability at different timescales) are highly energy dependent. We confirm that this trend is crucial at low energies.
This means also that when calculating coherence and lags, we cannot work with a broad reference band (lots of literature does!). So this is going to be fun - people will need to change their methods.
We also see a clear change in how the noise at low and hard energies is connected depending on the spectral shape of the source: when the spectrum is hard, the noise at different energies is coherent, implying a connection between the processes producing the noise (or the same process). When the spectrum is soft, this is not the case anymore.
We also see a rather puzzling feature in the hard state at low energies- a jump in time lag, accompanied by a loss of coherence.
We have some ideas what it may be, but no definitive answer. But we do see it in other sources, too! (We haven't seen it before because there was no instrument with NICER's spectral and timing coverage!)
Yes, parts V to VII of this series were my PhD thesis back in the days (and there are two more PhD thesis in the earlier papers of the series). Ole is proudly carrying on the work!
And it's also fun to see how we keep adding more pieces to the puzzle but also how much there is that we still don't know when it comes to variability.
There is far more than one PhD thesis in this source still :D
This image perfectly conveys just how huge the 100-m dish of the Green Bank Telescope is. I had the chance to visit it a few years ago, back when I lived in the US, and the view from the receiver room is stunning. Although I must admit that looking down through the mesh floor was... "an experience" 😵💫 😅
Citizen scientist Gerald Eichstädt made these images using raw data from the JunoCam instrument, applying processing techniques to enhance the clarity of the images.
Image credit:
Image data: NASA/JPL-Caltech/SwRI/MSSS
Image processing by Gerald Eichstädt