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) ?
This photo of a supernova appearing in spiral galaxy M101 is a gem for at least two reasons: - it is beautiful and it won a section of the Wikimedia Science Photo Contest and - it was taken by Serhiy Khomenko and it shows how there are people in #Ukraine, who despite the war and alarms and power cuts were able to even care so deeply about the universe in May 2023, and they still do now 💪
Kindly pointed to me by a colleague in 🇺🇦 credits and details ⬇️
Like in real life, also in extragalactic astronomy there are VIPs*. If you are into clusters of galaxies, the top of the VIP probably is the Coma clusters of galaxies, aka Abel 1656.
Given its latitude, from ESO's Paranal Observatory in #Chile you can see the core of the #MilkyWay passing directly overhead. In this pic I took a few years ago you can see its faint glow reflected off the dome of one of our 8 m telescopes.
My neck wasn't happy when framing this shot, though, as my camera doesn't have a flip screen! 😅
Cecilia Payne-Gaposchkin's 1925 thesis that the sun was composed mostly of hydrogen and helium was rejected by a professor who called it "impossible". Years later, the man who rejected it realized she was in fact right, but he was credited with the discovery for decades. A prominent astronomer called her discovery "the most brilliant PhD thesis ever written in #astronomy". #WomenInScience
A new #JWST view of the remnant of Supernova 1987A.
SN 1987A has been a target of intense observations at wavelengths ranging from gamma rays to radio for nearly 40 years, since its discovery in February of 1987. Located 168,000 light-years away in the Large Magellanic Cloud, it was the nearest supernova to explode in the era of modern telescopes.
Happy first anniversary, #NASAWebb! One year after beginning science operations, Webb is celebrating with a highly detailed image of the closest star-forming region to Earth. Peer deeper in the cloud: https://webbtelescope.pub/3JUoBTA
Like many other scientists I often get "debate me" emails from random people with weird ideas about #astronomy. If I answer, they feel validated. Same if I don't. So I always pick the option that doesn't waste my time. Don't fall for the "debate me" trap, folks, you can't win. #scicomm
The first #NASAWebb results from TRAPPIST-1 are in! Measurements of mid-infrared light from TRAPPIST-1 b indicate that the rocky Earth-sized planet is hot enough to bake pizza and is probably devoid of atmosphere. What does this mean? ➡️ https://webbtelescope.pub/3nlCcLc #space#astronomy#JWST#Trappist1b
For good #astronomy lectures aimed at general audiences, look at The Silicon Valley Astronomy Lecture Series; see link to YouTube via https://foothill.edu/astronomy/
(There I first attended a lecture on discovering exoplanets by Dr Geoff Marcy in 1996, which predated the series by a few years.)
For me, one thing that makes a lecture good is hearing what a speaker finds interesting about a subject.
Here's a picture of the Sun today that I took in hydrogen alpha. Compare that to a picture taken by NASA's Perseverance Rover a few hours ago with its Mastcam-Z. Sunspots 3216 (far-left) and 3214 (left) are visible on both. Even relative sizes check out.