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.
Don’t fuck with moon dust. No seriously, do not fuck with moon dust.
Absent any moisture or atmosphere, millennia of asteroid impacts have turned lunar regolith (soil) into a fine powder of razor sharp, glass-like particles. What’s more, the solar wind imparts an electric charge on the dust, causing it to cling to any and every surface it touches through static electricity. On earth, sand tends to get smoother over time as wind and water tumble the grains about, eroding their sharpness. Not so on the moon – lunar dust is sharp and deadly. This is Not A Good Time if you’re an explorer looking to visit our celestial neighbor.
During Apollo, the astronauts faced a plethora of unexpected issues caused by dust. It clung to spacesuits and darkened them enough that exposure to sunlight overheated the life support systems. Dust got in suit joints and on suit visors, damaging them. It ate away layers of boot lining. It covered cameras. Upon returning to the cabin, astronauts attempting to brush it off damaged their suit fabric and sent the dust airborne, where it remained suspended in the air due to low gravity.
Inhaling moon dust causes mucus membranes to swell; every Apollo astronaut who stepped foot on the moon reported symptoms of “Lunar Hay Fever.” Sneezing, congestion, and a “smell of burnt gunpowder” took days to subside. Later Apollo missions even sent a special dust brush with the team to help clean each other and equipment. We don’t know exactly how dangerous the stuff is, but lunar regolith simulants suggest it might destroy lung and brain cells with long-term exposure. 1
In fact the dust is so nasty that it destroyed the vacuum seals of sample return containers. We no longer have any accurate samples of lunar dust, “Every sample brought back from the moon has been contaminated by Earth’s air and humidity […] The chemical and electrostatic properties of the soil no longer match what future astronauts will encounter on the moon.” 2
Whats worse, the solar-charged dust gets thrown up off the moon’s surface via electrostatic forces. The moon doesn’t technically have an atmosphere, but it does have a thin cloud of sharp dust itching to cling to anything it can find.
And it probably isn’t just the moon. “A 2005 NASA study listed 20 risks that required further study before humans should commit to a human Mars expedition, and ranked "dust" as the number one challenge.” 3
The coolest solution I’ve heard about in next-gen spacesuit design is a mesh of woven wires layered into the suit. When activated, the wire mesh would form an anti-static electric field that repels dust. Quite literally a force field. 4 #astronomy#apollo#moon#lunardust
I've bloody well done it again! YUS! One year, every evening at 4pm (winter) 5pm (summer). A 20 second exposure through a pinhole camera, on a glass plate. I've captured the Analemma again! #analemma#astronomy#beauty
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) ?
(⚠️ 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)
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.
Mastodon est magique, j'en suis sûr.
Mon fils de 8 ans est passionné d'astronomie.
Nous lui avons promis un super livre sur ce sujet.
Nous sommes donc à la recherche du meilleur livre possible.
Parmi les astronomes amateurs et professionnel de mastodon, quel livre conseillez vous ?
Le retoot vous décroche la lune. #astronomy#astronomie#astrophotography#astrophysique
OK. :: sets down suitcase :: Looks like I've moved over here from mastodon.social.
Seem to have lost my follows, but I think I can rebuild that.
So how about a little introduction post? I'm a woman in her '60s, living in Southeastern Pennsylvania. I have a partner, a 10-year old son, two Schipperkes, and five hens.
The question I ask myself a lot these days is, how do we survive the next century cooperatively? I'm alarmed by the risk of authoritarianism here in the US.
#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.
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 👇
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?
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?
Thanks to a collaboration with my friend Stephen Voss, we present this composite image, taken over 3 nights last week. With Dunedin's Mount Cargill Tower as foreground, It shows the change in altitude of the sun over 3 nights caused by Earth's axial tilt and our motion around our parent star. It also shows the rotation of the sun over 3 Earth days (look at the sunspots and how they change position). Photos by me, processing by Stephen Voss. I love collaborations! #astronomy#NewZealand#sunset
If you could place any object on the surface of Mars, purely to confuse NASA scientists, what would it be?
For me i would just place like random paintings, like NASA would be very confused on why Mars would have paintings lmao.
SpaceX's Starlink internet satellites 'leak' so much radiation that it's hurting radio astronomy, scientists say (www.space.com)
Starlink satellites can disturb observation even of those telescopes protected by radio-quiet zones.
Could white holes actually exist? (www.space.com)
White holes are mathematically possible, according to general relativity. But does that mean they're actually out there?
The expansion of the universe could be a mirage, new theoretical study suggests (68k.news)
The expansion of the universe could be a mirage, a potentially controversial new study suggests....