Collecting some 1 GB of Hubble Space Telescope data, spanning more than 15 years, I was able to draw the orbit of Procyon B around the main star.

Due to huge magnitude difference, the double is one of the toughest to observe from the ground, so researchers were forced to request HST time to study the astrometry of the system (see Bond et al.). They say it was impossible to avoid saturating the CCD with the new WFC3 detector, so you can see the blooming in all the FITS.

The ellipse I obtained fits quite well with the white dwarf apparent orbit presented in the paper. Procyon B completes one revolution in around 40 years.

Unlike almost all stars, showing dark absorption spectra, Wolf-Rayets have emission lines clearly visible here against the background of the continuum, and as peaks of the intensity curve above. Thanks to their huge mass and temperature, which places them at the top left of the HR diagram, W-R stars are able to ionize even helium and nitrogen, extremely stable molecules.

Tormented by furious stellar winds, they are excellent candidates for ending their lives by exploding as supernovae.

Technical data

C8EdgeHD ♦ Star Analyzer 100 ♦ Apollo-M camera

R=6.2 Å/pixel

An attempt to resolve Ceres (the largest of the asteroids), in opposition those days. The third and fourth images were obtained with the camera rotated 90°; you can clearly see how the axis of the asteroid (which is cigar-shaped) rotates in accordance. For comparison, the last image shows the PSF of a nearby star. The image obtained (rescaled and blurred) matches almost perfectly with the Hubble image.

This image is one of the very few (among amateur ones) to clearly resolve this asteroid.

The white dwarf Sirius B (aka "The Pup") is in recent years at the maximum distance from the main star (more than 11″), so it is not difficult to spot in the glare of the primary, both visually and digitally. The optics must be very clean and the seeing conditions fair, at least. The diagonal reflection in the image is given by the ADC prisms, with the 4 secondary diffraction spikes superimposed. The processing is light, to give an idea of ​​how the double looks like at the eyepiece.

Technical data

14″ Newton (Zen optics) ♦ Player One Saturn-C camera

October 17, 2022

This animation had been assembled with images taken by the Japanese Akatsuki probe (Planet-C) in orbit around Venus. The instrument used was UVI (UltraViolet Imager), while the sequence spans approximately 6 1/2 days.

The size of the planet changes according to the distance of the probe. The famous Venusian Y is recognizable at the beginning and towards the end of the sequence.

South at top.

2016 June 22-28