In my earlier blog post (part 1), I posed the question of how some of the most energetic gamma-rays observed by the LHAASO and HAWC observatories can be created. In order to understand their origin, I drew an intuitive picture of how a photon can scatter off an electron at rest, usually called Compton scattering. The goal of this part is to take this a step further towards inverse Compton scattering, the case when the electron is instead moving at almost the speed of light. Inverse Compton scattering In all the earlier situations in part 1, the photon energy decreased or stayed the same at most. To increase the photon…

Neurodivergence is understood as a variation in human brain functioning that influences sociability, learning, sensory processing, movement and/or attention, among others (Kapp, 2020). The term encompasses a broader set of distinct conditions such as autism, ADHD or dyslexia. We understand neurodivergence as a spectrum, since it covers a wide range of conditions with varying levels of intensity and different ways they affect the life of a neurodivergent person. Some are fully capable of sustaining themselves, whereas others need to rely on support in all areas of life. Because neurodivergent experience varies on a case-by-case basis, each individual’s strengths and challenges are unique. For example, an autistic person can struggle with…

Did you know that light can bounce off a charged particle like an electron? And that this interaction can lead to some of the highest-energy gamma-ray radiation that we have ever observed in the universe? In this double blog post, I will build up an intuitive and visual understanding of how this quantum billiards between light and charged particles works (part 1) and how its relativistic version can explain some of the most fascinating astrophysical ultra-high-energy observations (part 2). Recently, the astrophysical community is flooded by exciting new observations from the Large High Altitude Air Shower Observatory (LHAASO) and High Altitude Water Cherenkov Experiment (HAWC). Both detectors are measuring light…

noun: imposter syndrome Unfortunately, the feeling of being a fraud merely skating by on luck is all too common in STEM fields. Women, under-represented minorities, and those early in their careers are particularly susceptible and therefore make up a disproportionate number of “imposter syndrome” sufferers.  As a community, there’s a lot of discourse about imposter syndrome and overcoming it on an individual level. But many of the suggested courses of action to combat these internalized feelings of fraud, such as “celebrate your successes” or “let go of perfectionism”, can read as empty platitudes that are typically much easier said than done. Crucially, these suggestions, although well-intentioned, focus more on what…

This month, I decided to write a blog post targeted at people outside of astronomy, to explain the reasoning behind one of the tools that we use. This is because I think the means and methods we have for exploring astrophysical phenomena are often as cool as the actual sources that we study, but often we don’t talk about how we go about discovering something. So, in this line, I’m starting simply, explaining the reasoning behind why we use a particular units system. Now, the title might be the first you’re hearing about this. And you might ask why we would ever, ever choose to measure the largest known things in the…

Using observations from 2017 and 2018, the Event Horizon Telescope (EHT) Collaboration has deepened our understanding of the supermassive black hole at the center of Messier 87 (M87*). If you read English or Dutch, I highly recommend checking out the official press release: M87* One Year Later: Catching the Black Hole’s Turbulent Accretion Flow, of het nieuws in de Nederlandse Onderzoekschool voor Astronomie (NOVA): Gas bij zwart gat M87 spiraliseert tegen draairichting in. I am proud to be quoted in the official press release, acknowledging the time and effort I devoted to that project. I performed statistical analyses to compare general relativistic magnetohydrodynamic (GRMHD) simulations with observations of M87*. My…

Some time ago, I was sitting at a family gathering when my grandmother asked me: “What is a black hole?”. I was in my second year of the astronomy bachelor’s in Chile, the first-ever image of the M87 black hole had just been made public by the Event Horizon Telescope and it was all over international news. I noticed that other people around me stopped their conversations and started listening to my response: “Well, you know how the Earth has gravity we can’t escape? That’s how we stay on the earth instead of flying into space. A black hole has such strong gravity that light cannot escape. Therefore, it’s a…

With the advent of the Christmas time, it is common to put yourself a nice candle in the living room (or sometimes even four or more). It is particularly nice to enjoy the warm and dim orange light, softly flickering and creating a cozy atmosphere. As an astrophysicist researching the light emission from outflows moving at almost the speed of light towards us, I was wondering what would happen to such a Christmas candle if I would do the same thing to the candle – move it at the speed of light. Clearly, the airstream would blow out the candle and it wouldn’t burn if we put it into a…

Astrophysicist by day, a music and pop-culture enthusiast by night, our very own Sera Markoff is elected as a member of the Koninklijke Nederlandse Akademie van Wetenschappen (the Royal Netherlands Academy of Arts and Sciences). This prestigious recognition underscores her contributions to the advancement of astrophysics and her role as a leading figure in both science and science outreach.  The Royal Netherlands Academy of Arts and Sciences, known as the KNAW (Koninklijke Nederlandse Akademie van Wetenschappen), is one of the oldest and most prestigious scientific organizations in the Netherlands. It serves as a key advisory body to the Dutch government on scientific matters, and its members are selected based on…