Dr. Mirel Birlan, researcher at Paris Observatory and the Astronomical Institute of the Romanian Academy is part of a team of researchers that has looked up-close at the Pallas asteroid, the third largest object in the asteroid belt, to better understand its unusual tilted orbit. The team discovered that the surface of the asteroid is so cratered, that researchers dubbed it “the golf ball asteroid”. The research team believes that the craters are a consequence of a violent period of collision during its history and that this could also explain the unusual inclination of its orbit that has puzzled scientists for centuries.
The Pallas asteroid is almost one-seventh the size of the Moon. For centuries, astronomers have noticed that the asteroid orbits along a significantly tilted track compared with the majority of objects in the asteroid belt. This inclination remained a mystery for a long time. Now a European team, led by principal investigator Pierre Vernazza from the Laboratoire d'Astrophyisque de Marseille in France, and including Dr. Mirel Birlan, obtained images of Pallas using ESO’s Very Large Telescope (VLT), an array of four telescopes, each with an 8-meter-wide mirror, situated in the mountains of Chile.
The high resolution images show a very cratered surface of the asteroid. In addition, the researchers created a reconstructed 3D model of the shape of the asteroid, revealing a heavily cratered object on the poles, but also at the equatorial regions. The researchers identified 36 craters larger than 30 kilometres in diameter, covering more than 10% of its surface — proof that Pallas experienced a violent period of collision during its history, two to three times more intense than the one of other large asteroids like Ceres or Vesta. The heavily cratered surface explains also the preservation of its initial shape after the formation. This collisional period could also explain Pallas’ tilted orbit.
The images of the asteroid have also revealed a bright spot on the surface of Pallas. The most probable explanation of this finding and its origin is that Pallas has large deposits of salts at its surface, most probably formed by a mixture of water and silicates. The investigations carried out by the European team have also led to the discovery of the Pallas family of asteroids, a cluster of small asteroids. Simulations of impacts with Pallas suggest that this family could be the result of a violent collision about 1.7 billion years ago by an object having a diameter between 20 km and 40 km. Asteroid 3200 Phaeton, identified as the source of the Geminids meteor shower, which is observed on Earth in December, is part of the Pallas family, and could provide clues to understanding the origin of the parent body, Pallas. Thus, observing meteors and collecting meteorites coming from Phaeton could partly solve the history of Pallas.
The findings were published in Nature Astronomy https://www.nature.com/articles/s41550-019-1007-5.
Published on Feb 20, 2020
Published on Feb 14, 2020
Berthelot Observatory is a remote observing station of the Astronomical Institute. Built on General Berthelot village, Hunedoara, on a protected area belonging to the Romanian Academy, the observatory is operated in remote mode from Bucharest. Following the first light in mid-November 2018, the observatory is currently involved in near-Earth objects photometric surveys and tracking and surveillance activities in the framework of EU-SST programme of the European Commission.
The telescope is a RC 14.5'' F/7 Optical Guidance System on a fast, 8°/s, equatorial mount able to track objects on medium Earth orbits. The field of view, using an SBIG STL11000M CCD camera, is of 44'x30'.
Berthelot Observatory successfully concluded the first common European exercise of space surveillance and tracking taking place from 15 to 24 July 2019. Astrometry data for the four assigned targets was provided daily in TDM format.
On December 6th, Berthelot Observatory received the code L54 from the International Astronomical Union's Minor Planet Center (MPC).
Published on Dec 06, 2019
The Institute was recently involved in two new ESA-funded research and development projects. Cheia Antenna Retrofit Phase II is a project led by RARTEL Telespazio, a Leonardo and Thales company, aiming to include the 32 meters antennas presently available at the Cheia Satellite Ground Station, in the context of European SSA programme. The Institute will assist RARTEL in all the project phases (design, software development, integration and testing) for all the aspects related to the tracking services which shall be supplied through the newly developed radar infrastructure.
SYNOPTES project, led by Romanian InSpace Engineeering startup and having both Cluj and Bucharest observatories as partners, is developing a GNSS-based real-time clock (RTC) system for the temporal synchronization of SST ground based observations. Berthelot and Feleacu astronomical stations are the testing beds and on-sky validation infrastructures of the technical solution. Contact: nedelcu (at) astro.ro)
Published on Nov 19, 2019
Bucharest Science Festival opened the gates of the Astronomical Institute of the Romanian Academy for the general public, on the 27th of September 2019. The number of visitors exceeded any estimations being around 500 adults and children.
The Planetarium Hall was permanently full of people eager to learn who participated to several presentations with PowerPoint, video or specialized software support. The academic staff and astronomy teachers were: dr. Diana Beşliu-Ionescu (AIRA), Daniel Berteşteanu (Bucharest Astroclub), Florin Zăinescu (University of Bucharest).
A special moment of the evening was the live connection with France, as dr. Mirel Bîrlan (AIRA) interacted with the public through Skype directly from Paris Astronomical Observatory.
The activities included guided tours in the museum halls of the Institute - the Meridian Hall and the Equatorial Dome. There, some of the most important and spectacular astronomical instruments of Romania are preserved for future generations and they are used today for educational purposes.The tour guides - Sorin Marin (AIRA), Octavian Blagoi (AIRA) and Marian Naiman (Bucharest Astroclub) received many questions during the whole event, especially coming from the younger friends of astronomy and they answered to all of them.
The members of Bucharest Astroclub took part in organizing the BSF 2019 event. They displayed with great openness their instruments - several telescopes and their accessories and kindly instructed the public on how to watch the planets and the stars through them.
Published on Oct 04, 2019
Using Berthelot Observatory in remote mode we imaged the first interstellar comet - C/2019 Q4 (Borisov) . Based on the current arc, the comet is on a hyperbolic orbit with an eccentricity of almost 3. The comet will reach perihelion on December 7, 2019. Berthelot Observatory will continue to monitor this objects in the following weeks. Contact: sonka (at) astro.ro.
Published on Sep 14, 2019
Romanian Astronomical Journal is an international journal covering the fields of:
Published on Aug 04, 2019
Asteroid (6478) Gault is a mysterious object; although it is in the Main Belt of asteroids, this object presents a cometary activity. During 2018 and 2019 astronomers detected a tail of matter in the asteroid's motion around the Sun, most likely due to the sublimation of light elements in its composition. The phenomenon involves the particles of dust and gas that reflect sunlight.
An international team that includes researchers from MIT-US, Astronomical Institute of the Romanian Academy, Weizmann Institute of Science in Israel, Observatoire de Paris-France, Lowell Observatory, Institute for Astronomy in Hawaii, and Northern Arizona University, has monitored the asteroid and obtained spectral and photometric data of Gault, between March and April 2019. Near-infrared spectral observations were performed in late March and early April 2019 with the 3 m diameter IRTF (NASA) telescope located in Mauna Kea-Hawaii; the spectral data were corroborated with the photometric data (Figure 1) obtained with the NEEMO-T05 telescope operated by the Astronomical Institute of the Romanian Academy.
Observational data confirm that the surface of the object contains minerals rich in silicium, most likely similar to the mineralogical composition of the asteroid family (25) Phocaea. The spectral data show variations of the spectral slope, decorrelated by a possible burst in object's cometary activity. This aspect can be explained by observing a new layer, unaltered by space weather, predominantly present on the surface of the object after the initial dust layer was entrained in the tail developed by the asteroid.
These results were recently published in the prestigious Astrophysical Journal Letters.M. Marsset, F. DeMeo, A. Sonka, et al., "Active asteroid (6478) Gault: a blue Q-type surface below the dust?” accepted in Astrophysical Journal Letters. Contacts: Adrian Sonka, Astronomical Institute of the Romanian Academy, Mirel Birlan, Paris Observatory.
Published on Aug 04, 2019
The Sun is the main driver of space weather. Space weather is determining the state of the Earth magnetosphere, which, in its turn, triggers geomagnetic storms.
Coronal mass ejections (CMEs) are pieces of the puzzle that drive space weather. They are one of the most important pieces, because of their large quantities of magnetised plasma released into the heliosphere. An Earth directed CME can hit the magnetosphere about 2-4 days after its initial detection, but not all CMEs arriving to Earth will produce a geomagnetic storm.
Numerous methods (theoretical, numerical and empirical) are being used to predict whether the CME will be geoeffective or not. In a recent paper, a team of researchers lead by D. Beșliu-Ionescu have proposed a new logistic regression model that will produce a probability, expressed as a number between 0 and 1, that a CME will be an event associated with a geomagnetic storm (Beșliu-Ionescu et al., 2019).
Published on Aug 03, 2019
Thursday, December 13, 2018, the Romanian Academy has presented the 2016 Awards. Dr. Magda Stavinschi has been granted the "Petre SERGESCU" Award for her books "Nicolae Coculescu, A Life Among Stars" and "The Astronomy and the Romanian Academy".
A novelty in the award presenting by the Romanian Academy is the initiation of the "Petre Sergescu" Award, intended for rewarding the best history of science and technology papers, award that will be given following consultations and votes from all science departments of the Romanian Academy.
The award was established 125 years after the birth of the great science historian, both for showing the importance that sciences have in the contemporary society development, and for honoring the memory of the prominent scholars with outstanding contributions, starting from the precept expressed by Auguste Comte, saying that "to understand science, it is to know its history".
Published on Dec 16, 2018