CERN Computing’s Post

The Floating Point is older than we thought. A new study reveals that the decimal point, a powerful mathematical tool enabling efficient calculations, was invented about 150 years earlier than previously believed, by a Venetian merchant named Bianchini. Previously, it was thought that the decimal point was introduced by the German mathematician Christopher Clavius in 1593. However, new research conducted by Glen Van Brummelen, a mathematician historian at Trinity Western University, shows that Bianchini was the pioneer of this notation. Bianchini, besides being a merchant, was an astronomy expert and published several works on the subject. He used the decimal point to separate the whole part from the fractional part of a number, such as 3.14159. The importance of the decimal point in mathematics is notable. Before its introduction, European astronomers used the sexagesimal system inherited from the Babylonians, which was complicated and prone to errors. Bianchini brought simplicity by expressing fractions in the base 10, greatly facilitating modern scientific and technological calculations. His approach, based on the practical arithmetic of merchants and accountants who used easily divisible real-world units, such as 12 inches per foot or 3 feet per yard, was crucial for this innovation.

📃Scientific paper: A fast photometric image alignment algorithm with row and column means Abstract: This paper introduces an astronomical image alignment algorithm. This algorithm uses the means of the rows and columns of the original image for alignment, and finds the optimal offset corresponding to the maximum similarity by comparing different offsets between images. The similarity is evaluated by the standard deviation of the quotient divided by the means. This paper also discusses the theoretical feasibility of this algorithm. Through practical testing, it has been confirmed that the algorithm is fast and robust. ;Comment: 7 figures Continued on ES/IODE ➡️ https://etcse.fr/h2 ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

📃Scientific paper: MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy Abstract: Over the past decades, libraries of stellar spectra have been used in a large variety of science cases, including as sources of reference spectra for a given object or a given spectral type. Despite the existence of large libraries and the increasing number of projects of large-scale spectral surveys, there is to date only one very high-resolution spectral library offering spectra from a few hundred objects from the southern hemisphere (UVES-POP) . We aim to extend the sample, offering a finer coverage of effective temperatures and surface gravity with a uniform collection of spectra obtained in the northern hemisphere. Between 2010 and 2020, we acquired several thousand echelle spectra of bright stars with the Mercator-HERMES spectrograph located in the Roque de Los Muchachos Observatory in La Palma, whose pipeline offers high-quality data reduction products. We have also developed methods to correct for the instrumental response in order to approach the true shape of the spectral continuum. Additionally, we have devised a normalisation process to provide a homogeneous normalisation of the full spectral range for most of the objects. We present a new spectral library consisting of 3256 spectra covering 2043 stars. It combines high signal-to-noise and high spectral resolution over the entire range of effective temperatures and luminosity classes. The spectra are presented in four versions: raw, corrected from the instrumental response, with and without correction fr... Continued on ES/IODE ➡️ https://etcse.fr/ipIcY ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

📃Scientific paper: A fast photometric image alignment algorithm with row and column means Abstract: This paper introduces an astronomical image alignment algorithm. This algorithm uses the means of the rows and columns of the original image for alignment, and finds the optimal offset corresponding to the maximum similarity by comparing different offsets between images. The similarity is evaluated by the standard deviation of the quotient divided by the means. This paper also discusses the theoretical feasibility of this algorithm. Through practical testing, it has been confirmed that the algorithm is fast and robust. ;Comment: 7 figures Continued on ES/IODE ➡️ https://etcse.fr/h2 ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

📃Scientific paper: The IACOB project XII. A new grid of northern standards for the spectral classification of B-type stars Abstract: With the advent of large spectroscopic surveys, automated stellar parameter determination has become commonplace. Nevertheless, spectral classification still offers a quick and useful alternative for obtaining parameter estimates for large samples of spectra of varying quality. We present a new atlas of stellar spectra covering the B-type range, with the intention of providing detailed classification criteria valid for modern spectra and improving the grid of reliable standards. This new grid will be used in future works to provide classification criteria beyond the classical classification range and addressing, in particular, the use of Gaia/RVS spectra. We analysed historical standards by means of multiple high-resolution spectra, marking out problematic cases and complementing the grid with a new set of reliable comparators. We then elaborated on a new set of classification criteria based on high-quality R=4000 spectra. Our new classification grid is much thicker than any previous set of standards, presenting a high degree of self-consistency. Although it is based entirely on morphological criteria, the grid demonstrates a much better correlation with different physical parameters. The new grid can be used to study classification criteria in other spectral ranges, providing a valuable tool for the study of B-type stars that covers a very wide range of temperatures, luminosities, and stellar masses. The very process of classification also offers valuable insights... Continued on ES/IODE ➡️ https://etcse.fr/3qnE ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

"Rescuing Science: Restoring Trust In an Age of Doubt" by Paul M. Sutter, Ph.D. is excerpted in Astronomy in this selection titled, “Why good science is needed more than ever, and so is good faith.” 📚 Find the new book: https://lnkd.in/eWEyWh5i https://lnkd.in/efcijgi4

Researchers have made a groundbreaking discovery by using gravitational wave research to unravel the mysteries of an ancient Greek computer known as the Antikythera mechanism. This nearly 2000-year-old device has puzzled scientists for years, but thanks to new analysis techniques, we are now closer than ever to understanding its complex workings. Dive into the fascinating details and see how modern science is shedding light on ancient technology! 📜⚙️ https://lnkd.in/d9g5evim

📃Scientific paper: Insight-HXMT on-orbit thermal control status and thermal deformation impact analysis Abstract: Purpose: The Hard X-ray Modulation Telescope is China's first X-ray astronomy satellite launched on June 15th, 2017, dubbed Insight-HXMT. Active and passive thermal control measures are employed to keep devices at suitable temperatures. In this paper, we analyzed the on-orbit thermal monitoring data of the first 5 years and investigated the effect of thermal deformation on the point spread function (PSF) of the telescopes. Methods: We examined the data of the on-orbit temperatures measured using 157 thermistors placed on the collimators, detectors and their support structures and compared the results with the thermal control requirements. The thermal deformation was evaluated by the relative orientation of the two star sensors installed on the main support structure. its effect was estimated with evolution of the PSF obtained with calibration scanning observations of the Crab nebula. Conclusion: The on-orbit temperatures met the thermal control requirements thus far, and the effect of thermal deformation on the PSF was negligible after the on-orbit pointing calibration. ;Comment: 25 pages, 35 figures, submitted Continued on ES/IODE ➡️ https://etcse.fr/JKD0a ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

Over the final year of my degree, I completed three projects in physics and astronomy to demonstrate the research skills I have developed throughout. The first was titled 'Signatures of Active Regions in Fe XIII' and involved using data from the Coronal Multi Channel Polarimeter at the Moana Loa observatory, to search for hot prograde flows in images of the Sun's corona. It was a great opportunity to learn image processing techniques in Python and continue to work in the field of solar physics. The second was titled 'The Slowdown Rate of the Crab Pulsar' and involved using data from the One Mile Telescope to measure the Crab pulsar's slowdown rate, characteristic age and magnetic field. This gave me the chance to learn the intricacies of pulsar timing, prevalent in gravitational wave research, as well as how to use Bayesian statistics. Finally, I completed an in depth literature review titled 'The Jupiter-Io System'. This greatly improved my analysis skills while I investigated the geology and atmosphere of Io. These projects have been great learning opportunities and I'm excited to continue developing these skills and implementing them in future projects.