Solex : Coronal Hole in HeID3

The entire day a blue sky, so perfect for an observation with my Sol'Ex. Before I started, the slit was cleaned using ethanol 96%. The result is much better then before.

Observation in H-alpha, MgIb2, HeID3, H-beta, CaIIH, H-epsilon and CaIIK.

HeID3 shows the coronal hole, facing towards Earth. It's shape is like a witch flying. 

Both H-alpha as CaII show activity.

It was also the first time I used a IR/UV L1 cut filter in stead of the IR cut filter. 

Seeing was between 1" and 2,5" (measured with SSM3), Sx/Sy was 1 and tilt < 0,5°.

Software: SharpCap, Inti, JSolex 5.6.1, CS4, AstroSurface.

Chasing X Tri: My First Variable Star Light Curve

Inspired by a fascinating presentation on variable stars at the Helios astronomy club, I decided to try my hand at capturing a complete light curve of my own. Locating the target proved a bit tricky with the ASIAIR interface, so I first centered on NGC 780 to get everything properly framed before locking onto the eclipsing binary X Tri (SAO72085). With high humidity threatening the session, I made sure to hook up my dew heaters to keep the optics crystal clear against the condensation. Using my TS-TLAPO80/480 refractor paired with the ASI2600MC camera, I carried out a continuous session lasting two and a half hours, taking ten second exposures to track the photometric variation reliably. For the reduction and photometry, I utilized ASTAP to extract and process measurements across the green, red, and blue channels. Analyzing the recorded magnitude values reveals the full eclipse event in clear detail, starting from an initial magnitude of 9.485, dropping smoothly down to a deep minimum of 11.119, and recovering back up to 9.323 magnitude by the end of the run. This yields a net observed magnitude drop of 1.63 magnitudes relative to the start. The measurements clearly trace the progression, with curve fitting pinpointing the exact minimum right around 20:38 UT, beautifully matching the prediction and giving me a tremendous rush to see real astrophysical data emerge from my own backyard setup.

Deep Space Spectroscopy Made Compact: The TinyStar’Ex Breakthrough

The world of amateur spectroscopy has taken a major leap forward with Christian Buil’s latest open-source project, the TinyStar’Ex. Building on the success of Sol’Ex and Star’Ex, this ultra-compact spectrograph is designed to bring faint-object astrophysics to modest backyard setups.

Unlike high-resolution predecessors that rely on heavy frames, TinyStar’Ex uses a lightweight housing and a low-resolution 300 line/mm diffraction grating paired with short focal length optics. This streamlined optical path maximizes light throughput, allowing observers to capture the full visible spectrum of faint targets like supernovae, comets, and variable stars in a single exposure.

By drastically cutting down overall length and weight, TinyStar’Ex solves the common issue of mechanical flexure on telescope focusers, ensuring precise alignment throughout long imaging sessions. Entirely 3D-printable and fully compatible with processing tools like SpecINTI, it offers an accessible way for amateur astronomers to gather scientifically valuable spectral data.

See more this link: https://tse-spectro.net/

For the optics we need to wait untill November 13: https://www.univers-astro.fr/en/spectroscopy/1975-tinystar-ex-tse-optical-kit-for-spectrograph-lenses-slit-and-grating.html

Inspiring Lectures by Eva Laplace and Matthew Kenworthy at the VVS Weekend

During the fortieth edition of the JVS/VVS weekend in the Duinse Polders, we had the pleasure of attending several fantastic scientific lectures. Prof. dr. Matthew Kenworthy from Leiden University delivered an impressive presentation on exoplanets and exomoons. He demonstrated how his team successfully captured cosmic disks that potentially represent young exoplanets or colliding exomoons. 

On the second day, dr. Eva Laplace took us into the fascinating world of binary stars and their crucial role in supernovae, black holes, and gravitational waves. During a subsequent discussion, she explained how her software TULIPS provides insights into type Ia supernovae and the Hubble tension. Both speakers added extra brilliance to this anniversary weekend and greatly inspired all the amateur astronomers present.

Highlights from the August 12 Solar Eclipse Featured in Magazine Heelal

The November issue of Magazine Heelal prominently features both the collective efforts of VVS Section Helios and my personal journey during the solar eclipse of August 12, 2026.

During the event, VVS Section Helios hosted a public observation at the Maagdentoren in Zichem, welcoming around a hundred visitors to safely view the partial eclipse and promoting upcoming astronomical events. Meanwhile, four members of our section—Walter Swinnen, Johan Reviers, Roger Marien, and Pascal Hilkens—traveled to Spain to experience totality. Observing across locations like Covarrubias, Burgos, Autilla Del Pinto, and Carrion de los Condes, the team captured remarkable footage—including drone imagery of the solar ring—and witnessed 1 minute and 46 seconds of totality.

We are delighted to see these experiences published in Magazine Heelal. You can read the full accounts and view the photographs in the latest November issue.

Boarding Pass Dragonfly to Titan

In 2028, NASA launches its Dragonfly rotorcraft toward one of the most extraordinary destinations in the solar system: Saturn’s moon Titan. I signed up to have my name placed on a chip aboard Dragonfly and got my personalized Boarding Pass for this daring exploration adventure.

The 24th Solvay Public Lectures with Nobel Laureates Kip Thorne & David Gross

 

What an absolute privilege to stand face-to-face with true legends of physics this weekend! This past Sunday, during the special public session of the 24th Solvay Lectures at Flagey in Brussels, four of us from Helios astronomy club had the incredible opportunity to attend together—and I even managed to grab selfies with none other than Nobel laureates Kip Thorne and David Gross.

Walter, Pascal, Lieven, Fernando from Helios

The event was entirely dedicated to gravitational waves and the deepest mysteries of our universe. Kip Thorne—who won the Nobel Prize in 2017 for his decisive contributions to the LIGO detector project and the historic first-ever detection of gravitational waves—delivered a fascinating lecture titled "Probing Black Holes with Gravitational Waves". He brilliantly explained how these ripples in spacetime allow us to uncover the secrets of black holes. Alongside him, theoretical physicist Claudia de Rham took the stage to speak about testing the fundamental nature of gravity, after which David Gross expertly moderated the panel discussion that followed.

Kip Thorne

Claudia De Rham

Witnessing and meeting these brilliant minds becomes even more awe-inspiring when you realize the groundbreaking work they have accomplished. Kip Thorne earned his Nobel Prize for capturing the very first whispers of spacetime, proving Einstein’s century-old prediction about gravitational waves. David Gross, on the other hand, was awarded the Nobel Prize in Physics back in 2004—alongside Frank Wilczek and David Politzer—for the discovery of asymptotic freedom. Together, they unlocked how the strong nuclear force works and how quarks behave deep inside the smallest building blocks of atomic nuclei.

To cap off an already unforgettable day, we were treated to a lavish, grand reception after the presentations, giving our Helios group the perfect opportunity to raise a glass and process everything we had just experienced. From the subatomic particles that Gross unraveled to the colossal black holes that Thorne and De Rham brought to life, attending this Solvay Conference alongside fellow Helios members is a memory we will cherish for a very long time.

Selfie with Kip Thorne

Selfie with David Gross