Majadahonda Astronomical Observatory

On April 3rd, 2026, I acquired the spectrum of the supernova SN 2026fvx using a spectrograph based on a Star Analyzer SA100 diffraction grating adapted to operate with a 35-micron slit. The observation consisted of a sequence of 15 exposures of 300 seconds each, resulting in a total integration time of 1 hour and 15 minutes. Although the Star Analyzer is commonly used in slitless configurations, in this case it was adapted into a slit spectrograph configuration, significantly

Artistic representation of Haumea and its ring system (cover of JOURNAL FOR OCCULTATION ASTRONOMY, Volume 16, No. 2) The observation of the occultation by Haumea on May 4th, 2026 represented a particularly relevant scientific opportunity for the study of trans-Neptunian objects. These types of events make it possible to obtain extremely precise information about the size, shape, density, and environment of these distant bodies by analysing the momentary disappearance of a sta

On May 1st, 2026, we carried out a new stratospheric balloon launch as part of the Balloon Probe project coordinated by the Agrupación Astronómica de Madrid (AAM) in preparation for the total solar eclipse of August 12th, 2026. This date was deliberately selected because the position of the Sun closely reproduced the same geometric conditions expected on the day of the eclipse, allowing tests to be performed under conditions very similar to the real event. The payload incorpo

3I/ATLAS was discovered on July 1, 2025 . It was first detected by the ATLAS telescope in Río Hurtado, Chile, when it was approximately...

When primary cosmic rays collide with atoms in the Earth's atmosphere, unstable particles such as pions and kaons are produced. As these particles decay, they generate muons and neutrinos. By constructing a muon detector, we are able to record secondary cosmic rays. Its construction is a very interesting project and opens the door to our knowledge and experimentation in the field of high-energy astrophysics. You can read more at: Muon Detector

The AAVSO has kinly sent me an acknowledgement for “ your invaluable contribution of over 2,500 variable star observations by...

FlashTime is a light flash generator synchronized with the PPS (Pulse Per second) of a GPS. It allows to generate light pulses to be...

I'm sure you've heard of AllSky cameras, but what is a HowSky camera? It is actually an invented concept: a camera with a wide field of...

ESA's Gaia mission has catalogued nearly 12 million variable stars, published in 2022 through Gaia Data Realease 3 (Gaia DR3). The...

I have added a new project to the website https://www.observatorio-majadahonda.com/motorised-flip-mirror which explains how to automate a...

Photometric observation of asteroids is one of the most interesting activities for amateurs. To analyse the rotation of an asteroid it is...

The supernova SN2023BEE, discovered on 1 February 2023, has been extensively photographed and measured, most notably by the Supernova...

b Persei (which is not the same as beta Persei, Algol) is an exciting triple star system with a hierarchical structure. The main part of...

How to help as an amateur to answer this question. Europa is, along with Io, Ganymede and Callisto, one of Jupiter's four largest...

In January 2021, a double (actually triple as we shall see) star was occulted by the asteriode Egeria. This post explains my experience...

The Minor Planet Center published in the bulletin "volume 49, number 2" corresponding to the period April to June 2022, a work of the...

The summer holidays are a good time to undertake new astronomy-related projects that are adapted to the circumstances of being on the...

Many thanks to the AAVSO for their recognition of the report of more than 1,000 photometric measurements with the PEP (Photoelectric...

Occultations of stars by the Moon are of interest in astronomy for measurements of lunar topography, measurements and even discovery of...

In this video you will see an eclipsing binary star system like you have never seen before ... I hope you enjoy it. It was prepared for a...