Here it is, several thousand years in the making: the protostellar jet HH212 as seen in the infrared by #JWST.
We discovered this jet in 1993, glowing in the light of shocked molecular hydrogen at 2.12 microns, as gas emerges symmetrically at about 100 km/s from the two poles of a young protostar not far from the Horsehead Nebula in Orion.
Our new JWST image spans six wavelengths & is ten times sharper than any previous infrared image.
Want to know what my research is about? Follow this thread 🧵 based on a 10min talk I've drawn for a meeting.
The talk was aimed at non-specialist space science colleagues (not the general public!). The slides were built up step by step, but I'm omitting this here & showing only the final graphs, less this becomes a 34-part thread. 11 is plenty enough!
So: "Understanding Winds of Massive Stars Using High Mass X-ray Binaries"
The first results from my #JWST time, in a project shared with Tom Ray et al. from the MIRI consortium, a study of the extremely young protostellar outflow, HH211, in Perseus, published in advance form in Nature today.
All right, I've just learned that it was my #Fediversary yesterday and I have a new paper out on arxiv today, so let's celebrate all that with an #astrodon 🧵 on magnetized accretion, and it's surprising connections with turbulence in ... pipes ! It's quite a ride in terms of research story
(⚠️ some modifications to the numbers I quoted here: https://mastodon.social/ - the upper estimate of the escape time from the Sun were exaggerated, following too old references)
A new #AstrophysicsFactlet prompted by a smart question posed by a student of my Astroparticle course for astronomers.
In a nutshell: why the maximum energy of the #CosmicRays we can capture as they collide with the atmosphere of our planet is so much bigger than the maximum energy of the cosmic rays we can accelerate with human made accelerators, like the Large Hadron Collider (LHC) ?
Hope Mars Mission
Time: 2023-05-23 00:33
Orbit 377
Filters: f635+f546+f437, f320 used to slightly enhance the orographic cloud over Ascraeus Mons
Processed from: https://sdc.emiratesmarsmission.ae
The Event Horizon Telescope has unveiled how Sagittarius A*, the supermassive black hole at the centre of our galaxy, looks like in polarised light, which tells us a lot about the magnetic field around this monster.
The lines overlaid on the image below mark the orientation of the polarisation, from which astronomers can work out the structure of the magnetic field around the black hole.
#AstroPhysicsFactlet about the propagation of cosmic rays.
Cosmic rays are particles (mostly protons, occasionally also heavier nuclei or leptons) that move basically at the speed of light.
The most energetic cosmic ray ever recorded moved at a speed which is 99,99999999% of the speed of light.
And yet, unlike photons, cosmic rays even so fast do not move in a straight line, but along this drunk trajectory in the figure.
"Good morning Sir...this is the invitation to attend a multi-cultural initiative to promote a dialogue between science and spirituality in an unbiased way...would you please join us....by the way it's going be hosted in a MONASTERY WITH MONKS"
etc etc
No, thanks no!
My bottom line here is that no, I think that while people have their spirtuality, there should be no legitimacy for an equal ground dialogue between science and sprituality.
1/ This is the longest exposure I've ever taken: 8 months long! It shows the Sun's path on the sky between Apr 17 - Dec 11 2018, as seen from ESO's Paranal Observatory in #Chile.
This is part of a collaboration with Diego López Calvín, an expert in solarigraphy: https://solarigrafia.com
Diego sent me some of his hand-made #pinhole cameras, which I placed all over Paranal. So what do we see here? See thread below 👇
Allez j'ai fini mon rapport en retard.. Vu que c'est une journée où j'échange sur la physique apparemment, je profite de la fin d'après-midi pour tooter un petit thread sur l'utilisation des harmoniques sphériques en physique, et plus spécifiquement dans le contexte de la cosmologie, thread qui avait été posté en diffusion restreinte il y a quelques semaines #astrodon#outreach 🧵
Simulations in astrophysics are getting larger and larger, and so is the global population on our planet.
The simulation on the left is the largest simulation I have ever run (on the Piz Daint supercluster at CSCS in Lugano, Switzerland) and is one of the largest ever in simulation with magnetic fields in cosmology.
Are there more people on Earth now, or cells in my simulation?
By extrapolating some numbers based on local measurements, we can guess there are about 1e12-1e13 galaxies just in the observable part of our Universe, for a total of at least~1e24 stars.
When did the Universe form them? How well do we know?
How far did astronomers travel world-wide for conferences in 2019 in total? More than 300 times to the Moon & back! Or, to put it in astronomical units: more than 1.5 AU, so to the Sun and halfway back!
A 🧵 summarizing our paper "Astronomy’s climate emissions: Global travel to scientific meetings in 2019" - published today, lead by Andrea Gokus (who also wrote the draft for this thread) and @knud, with many people, among them @leo & me, contributing:
First light with XRISM 💡 🛰️ ! The X-ray telescope launched in September and has an imager developed by JAXA (Xtend) & spectrometer developed by NASA (Resolve). An observation from both is shown in the press release!
There is one blip: the protective beryllium dewar aperture door on Resolve should be removed, but it's currently stuck. High energy X-rays can pass through this, but lower energies are absorbed. The team will shift conditions a bit and try again.