Amateur astronomer Gennady Borisov identified a new celestial object in the Solar System, designated as C/2025 V1, in observations carried out at the MARGO Observatory, in Crimea, on November 2, 2025. The finding occurred during monitoring of other astronomical phenomena and was confirmed by international teams within a few hours. Experts are evaluating whether the body represents the fourth known interstellar object, due to its possible hyperbolic orbit, which suggests origins outside our system.
The absence of a visible tail on the object, despite its proximity to the Sun, intrigues scientists, who provisionally classify it as a long-period comet.
The announcement reinforces the role of independent observers in modern astronomy.
- Initial discovery on November 2, 2025, in the northern hemisphere.
- Confirmation by the International Astronomical Union via CBET nº 5631.
- Orbit with eccentricity of 1.0095, indicating an open trajectory.
Preliminary object trajectory
Initial calculations indicate that C/2025 V1 follows a route that brings it 103 million kilometers closer to Earth on November 11that of 2025.
Perihelion, the closest point to the Sun, should occur on November 16, 68 million kilometers away.
Astronomers monitor whether gravitational perturbations will alter this data.
Discovery Top Moves Timeline
- November 2: Borisov detects the object during routine observations in Crimea, with an apparent magnitude of 14.2.
- November 3: First confirmations from telescopes in Russia, Japan and Chile reveal active coma, but no tail.
- November 5: Official report to the Minor Planet Center catalogs it as a possible hyperbolic comet.
- November 10: Analysis indicates origin in the Oort Cloud, with permanent exit from the Solar System.
- November 11: Maximum approach to Earth, allowing new images that show faint disintegration.
Connection to past interstellar objects
Gennady Borisov gained notoriety in 2019 for discovering 2I/Borisov, the second confirmed interstellar visitor after 1I/Oumuamua in 2017. These findings established a pattern of hyperbolic trajectories, with speeds above 26 km/s relative to the Sun. C/2025 V1 exhibits similar characteristics, such as mass shrinkage estimated at 0.4% before perihelion, although no evidence of gas ejection as in 2I.
The sequence of discoveries, including the recent 3I/ATLAS in July 2025, suggests that such interlopers are more common than previously thought, possibly originating in nearby star systems.
Initial observations and physical characteristics
The object has a core estimated between 1.4 km and 16 km in diameter, with a rotation of 13.2 days detected by satellites such as NEOSSat. Its composition includes ice and dust, typical of comets from the Oort Cloud, a region outside the Solar System with billions of similar bodies. Observations on November 3 indicated a “ghostly” appearance with no defined nucleus, which may indicate early disintegration.
Telescopes on the ground and in space, such as those in Chile and Austria, have captured tailless images, attributed to the initial distance and low sublimation activity.
International monitoring underway
Teams from NASA and ESA monitor C/2025 V1 with radars and spectrometers to measure chemical composition. The speed of 210 km/h relative to the Sun reinforces the interstellar hypothesis, although initial measurement errors may adjust the eccentricity below 1.
The find highlights the global network of amateur observatories, with contributions from the Czech Republic and other countries.
Daily updates from the Central Bureau for Astronomical Telegrams provide refined orbital data, with no indication of hazards to Earth.
Implications for current astronomy
Discoveries like this expand the catalog of long-period objects, with moreof 3 thousand similar comets recorded. C/2025 V1, if confirmed as interstellar, would bring the total to four, accelerating studies on the formation of stellar systems.
Research with Hubble and the James Webb Telescope plans post-perihelion observations to detect radio emissions or brightness variations.
