Imminent Asteroid Impactor 2024 BX1 near Berlin

21st of January 2024

A very exciting night of observations has come to an end…

It started with the Meerkat alarm (ESA’s imminent impactor warning system) from NEOCC at 23:36, which was triggered by the publication of observation data of a new asteroid. A 100% heliocentric impactor with a size of 1 m was predicted to arrive in Germany or Northern Europe in the next few hours. It was quite surprising, as it had a 100% impact probability with such few observations. This rarely happens. Since it is also an object with a heliocentric orbit, it is very likely that it really is a natural object, such as a NEO (Near-Earth Object), and not an artificial satellite or similar.

We started the GHOST telescope at the university observatory within a few minutes. The weather was quite cloudy, but dry and there was still some hope of small gaps in the clouds.

In the meantime, other ESA employees became also aware of the alert. At 23:53, the Meerkat Alert was updated with new data. The parameters of the asteroid were still confirmed, but the impact time will be confirmed within the next 2 hours and the impact corridor is located in the Berlin/Brandenburg area.

At the same time, GHOST attempted to take its first measurements of the object. Despite the clouds, cloud-free images were occasionally taken, but these could not be analyzed with sufficient accuracy.

At 00:08, the impact period was further narrowed down to around 00:30 UTC with additional observation data from Meerkat. In the meantime, there was no longer any doubt in the community that this was a real object. Distribution lists such as the Minor Planet Mailing List were used to reach scientists worldwide and in particular to find observers in the region who were still awake.

In the meantime, GHOST produced analyzable images. However, it turned out that the object was now moving so fast in the sky that the telescope could no longer keep up with the measurements in the narrow field of view before the object moved out of the image. In addition, there were much larger systematic errors in the current position data of the object from the MPC, as these do not take Earth and Moon gravity into account when calculating the orbit of the object and this has now become a dominant effect due to the proximity of the Earth. In the end, GHOST looked in the wrong areas and was therefore unable to record the object despite the fact that some areas were cloud-free.

At the same time, all possible Allsky cameras (AllSky7 and FRIPON) at the observatory and in the Berlin/Brandenburg region that we supervise were checked for functionality in order to be able to detect the soon arriving fireball.

Further observations of the asteroid were recorded all around Europe, even up to 15 minutes before the impact, until the object disappeared into the Earth’s shadow and could no longer be seen. Links to webcams in Berlin were shared around worldwide to follow the event live, and a final appeal was quickly made to colleagues in the Berlin area to please look up into the sky and record it with cameras if possible. With nothing more to do, it came the time to just wait…

… We held our breath and at 01:32 the time had come …

The meteor was clearly visible on webcams, the prediction came true, exactly as shown in the calculations! People in the region clearly saw the very bright glow, which only lasted a few seconds. At its maximum, however, the fireball was brighter than the moon! A colleague in Berlin recorded the whole event with his camera (see Video) and made the recording available to us for evaluation and submission to IMO. More pictures and video were shared worldwide. People congratulated and congratulated each other. People from all over the world came together for a moment and worked together to capture this small 1 m rock for as long as possible with as many cameras and eyes as possible. What a spectacle!

In the meantime, the asteroid has been published by the MPC (https://www.minorplanetcenter.net/mpec/K24/K24B76.html) and initial measurements have been collected by the IMO (https://fireball.imo.net/members/imo_view/event/2024/423). Further evaluations will certainly follow tomorrow. It is possible that a meteorite can be found 20 km west of Berlin in fields and meadows…

Have a good search!

Video of fireball from C.T. (Berlin area)
AllSky7 Station AMS95 (Oldenburg), allsky7.net

FRIPON Kamera Ketzür (DEBB01)



University Observatory discovers five new Minor Planets in one night

The GHOST telescope of the University Observatory of Oldenburg (IAU Code: G01) reached another milestone in the asteroid and comet observation field: During the night of 17th to the 18th of October 2023 the telescope was participating in the discovery of five new small objects in the solar system, which have all been published by now. Among these five objects there are three Near-Earth Asteroids (NEA), one of which is a previously known but lost asteroid (2014 XL8), which has not been observed anymore since 2014. The other two objects are both comets, which first seemed to be asteroids, too, but later analysis showed a visible coma in the images. In fact, one of the two comets is a Near-Earth Comet (NEC), which is quite rare, only making up around 0.4% of the more than 33.000 Near-Earth Objects (NEOs).

Here a summary to all discovered objects with their publication:
– 2023 UW (NEA): https://minorplanetcenter.net/mpec/K23/K23U80.html
– 2014 XL8 (NEA): https://minorplanetcenter.net/mpec/K23/K23U93.html
– 2023 UZ1 (NEA): https://minorplanetcenter.net/mpec/K23/K23UB5.html
– C/2023 T2 (Comet): https://minorplanetcenter.net/mpec/K23/K23UG2.html
– C/2023 S3 (NEC): https://www.minorplanetcenter.net/mpec/K23/K23V01.html

With these new discoveries, the GHOST telescope has now discovered 11 Minor Planets since the operational start in 2022, 9 of those this year.

For further information on the GHOST telescope please have a look on this page: https://wp.uni-oldenburg.de/asf/robotische-teleskope/ghost/


GHOST discovers Potentially Hazardous Asteroid “2023 RW9”

In the night of the of the 13th September 2023 at 03:41 UTC, the 0.50 m ATLAS telescope in Chile found a fainter object (18-19 mag) moving in the sky. The observatory submitted its measurements, as it is the typical procedure, to the MinorPlanetCenter (MPC) of the IAU. Other observatories throughout the world tried to find this object too. After first confirmatory observations it became clear that the observed object is an asteroid with around 140 m diameter (H=22) and a minimal orbital intersection distance (MOID) with Earth of around 0.05 AU (~19 lunar distances), but with no chance of hitting Earth. Nevertheless, this object is classified as a “Potentially Hazardous Asteroid” (PHA).

In order to refine the orbit and characterize the object more accurately, more observers did measurements of the position and brightness of the object and also submitted them to the MPC. The university observatory of Oldenburg with the 0.40 m GHOST telescope observed the PHA on the 15th of September from 00:25 UTC until 2:24 UTC with accurate measurements (cf. image below). With these last measurements, the asteroid was ready to be published as the orbital uncertainties were reduced appropriately, so that regular measurements in the next years can verify the predicted orbit without the chance of loosing the asteroid.



Erneut erdnahen Asteroiden entdeckt

In der Nacht vom 08. Februar 2023 hat das “Große Hauptteleskop der Oldenburger Sternwarte” (GHOST) erneut einen erdnahen Asteroiden, sogenannte NEOs, entdeckt. Dies ist bereits das dritte Objekte, welches mit dem Teleskop entdeckt wurde. Der provisorische Name lautet “2023 CS”.

Die Entdeckung verlief in Kooperation mit mehreren Teleskopen weltweit. Zuerst wurde das Objekt von dem Teleskop der Catalina Sky Survey einige Stunden vor der Beobachtung in Oldenburg entdeckt. Zusammen mit weiteren Daten von 10 Teleskopen weltweit konnte das Oldenburger Teleskop dazu beisteuern, dass die Bahn und Größe des Objekts genauer bestimmt werden konnte.

Es handelt sich bei “2023 CS” um einen erdnahen Asteroiden mit einer Größe von etwa 150 m (angenommener Albedo: 0.15). Der minimale Abstand des Objekts zur Erdumlaufbahn beträgt 0.066 AU, was 25 Mondabständen entspricht. Der Asteroid hat somit einen zu großen Abstand, um mit der Erde potenziell kollidieren zu können und wird daher nicht als gefährlich eingestuft.

Veröffentlichung zum Objekt: https://minorplanetcenter.net/mpec/K23/K23C60.html

Veröffentlichung zum Teleskopsystem: https://www.frontiersin.org/articles/10.3389/fspas.2022.895732/full

Bild: Tobias Hoffmann, Universitätssternwarte Oldenburg (G01)

Allgemein Smart Telescope

Oldenburg University Observatory most active telescope in Northern Europe

The University Observatory of Oldenburg achieved to make the most observations of asteroids, comets and Near-Earth Objects (NEOs) in the northern Europe area in 2022. All these observations of all observatories world-wide are collected and used by the MinorPlanetCenter (MPC) of the International Astronomical Union (IAU). In total, the Oldenburg telescopes made 576 observations in this year, which is the most in Northern Germany [1] and Northern Europe [2].

Most of the observations were made with the “Große Hauptteleskop der Oldenburger Sternwarte” (GHOST), a 40 cm Ritchey-Chrétien-Telescope. It was transformed to a robotic telescope in 2021 for asteroids detection and since then continuously makes observation, when the weather is suitable. The robotic observation pipeline was published in October 2022 and can be accessed here under [3].

If you are interested in the observatory and its telescopes, please feel free to contact us: astrophysik@uol.de

[1] Northern Germany includes: Bremen, Berlin, Hamburg, Schleswig Holstein, Mecklenburg Western Pomerania, Brandenburg and Lower Saxony
[2] Northern Europe includes in this case: Northern Germany, Denmark, The Netherlands, Iceland, Norway, Sweden, Finland, Estonia, Latvia and Lithuania
[3] https://www.frontiersin.org/articles/10.3389/fspas.2022.895732/full


Universitätssternwarte im Adventskalenders

Die Universitätssternwarte wurde im Türchen “18” des Adventskalenders der Universität Oldenburg gefilmt und einen kurzen Einblick in das “Große Hauptteleskop der Oldenburger Sternwarte” (GHOST) gegeben und über die Arbeit der Sternwarte berichtet.

Mit dabei waren Prof. Dr. Björn Poppe (AG Medizinische Strahlenphysik und Space Environment), einer der Leiter der Sternwarte, sowie Tobias Hoffmann (Master Physik Student), zuständig für die Beobachtungen des Teleskops.

Ein großen Dank an Frau Silke Rudolph von der Abteilung Presse & Kommunikation der Universität Oldenburg für die tollen Aufnahmen und den Zusammenschnitt!

Quelle des Videos und mehr Informationen: https://uol.de/advent


Recovery of lost Near-Earth Asteroid 2005 XW4

In the night of the 14th of December the “Großes Hauptteleskop der Oldenburger Sternwarte” (GHOST) of the university observatory of Oldenburg (G01) was able to recover an Near-Earth Asteroid (NEA) that was missed for 17 years. At first, it was believed that the detected object was a new discovered asteroid, but after several observations of 25 observatories worldwide it became clear that the orbit is identical with the object “2005 XW4” or “K05X04W” which could not be observed anymore since the end of 2005 and the predictions of the orbit were too uncertain. The Oldenburg telescope was one of the first telescopes worldwide that observed the object after the ATLAS telescope at Haleakala (T05), Hawaii, initially (re-)found the object about 10 hours prior. With a visual magnitude of about 18 mag it was a relativly bright NEA, thus many observatories were able to make observations.

2005 XW4 was first discovered at Lincol Laboratory ETS in New Mexico on 6th of December 2005. It is an Near-Earth Asteroid (NEA) with a diameter of 160 m (assuming albedo of 15%) and a minimal orbital intersection distance with Earth of 0.06866 AU (10.3 Million km or about 27 moon distances). Eventhough it is currently not considered a risk according to the ESA risk list, since to current measurements it will not hit Earth in the future, it should be observed frequently to improve the predictions. The goal is that the object is not lost again. This is why the Oldenburg telescopes are observing the object as long as it is close and bright enough.

This is now the second time the university observatory was able to help find objects from the “NEO Confirmation Page” of the MinorPlanetCenter. Since launch of the NEO observation system in Oldenburg, both telescopes of the university observatory, GHOST and ORT, made more than 800 follow-up observations of small objects in the solar system. They submit their measurements to Minor Planet Center (MPC), which combines measurements from observatories all around the world and calculates precise orbits of these objects. This ensures that all objects that could be dangerous for Earth are tracked. An original research article was published in October about the system in Oldenburg. It can be read here: https://www.frontiersin.org/articles/10.3389/fspas.2022.895732/full

More Information on the object 2005 XW4:

Animation of the measurements of the Asteroid “2005 XW4”
Astrofotography Deep-Sky-Objekt


TS-Optics 16” f/8 RC Teleskop (406/3250 mm)
ATIK 383L+ CCD Kamera, -15 °C

Merge from 4 Pictures with 0.5 s exposure at Bin 1×1