Image Archive: Solar System

Images of the different hemispheres of the asteroid Ceres, the largest object in the main asteroid belt that exists between Mars and Jupiter. 

Als Objekt im Asteroiden-Hauptgürtel erfüllt Hygiea gleich drei der vier Voraussetzungen, um als Zwergplanet eingestuft zu werden: Er umkreist die Sonne, er ist kein Mond und hat im Gegensatz zu einem Planeten die Nachbarschaft um seine Umlaufbahn nicht freigeräumt. Die letzte Anforderung ist, dass er genügend Masse hat, um sich durch seine eigene Schwerkraft in eine nahezu kugelförmige Form zu ziehen. Das ist genau das, was die VLT-Beobachtungen nun zu Hygiea ergeben haben.

Neue Beobachtungen mit dem SPHERE-Instrument der ESO am Very Large Telescope haben gezeigt, dass der Oberfläche von Hygiea der riesige Einschlagkrater fehlt, den Wissenschaftler eigentlich auf ihrer Oberfläche erwartet hatten. Da sie bei einem der größten Einschläge in der Geschichte des Asteroidengürtels entstand, hatte man mit mindestens einem großen, tiefen Einschlagbecken gerechnet, ähnlich dem auf Vesta (unten rechts in der Mitte).

Die neue Studie ergab auch, dass Hygiea annähernd kugelförmig ist und möglicherweise von Ceres die Krone als kleinster Zwergplanet im Sonnensystem übernimmt. Das Team nutzte die SPHERE-Beobachtungen, um die Größe von Hygiea zu bestimmen, wobei der Durchmesser etwas über 430 km beträgt, während Ceres fast 950 km groß ist.

Dieses Bild zeigt einen Kometen im Randbereich des Sonnensystems: Komet C/2016 R2 (PANSTARRS). Wie sein Name schon andeutet, wurde er im Jahr 2016 von den Pan-STARRS-Teleskopen auf Hawaii entdeckt. Das neue Bild, das wir hier sehen, wurde im Rahmen eines Projektes am Paranal Observatorium der ESO in Chile namens the Search for habitable Planets EClipsing ULtra-cOOl Stars (deutsch: Suche nach bewohnbaren Planeten in der Nähe ultra-kühler Sterne) oder kurz SPECULOOS aufgenommen.

Kometen sind Ansammlungen aus Staub, Eis, Gas und Gestein. Wenn sie der Sonne näher kommen, erwärmt sich ihr Eis, wird zu Gas und entweicht in einem Prozess, den man als „Ausgasen“ bezeichnet. Durch diesen Prozess entsteht eine diffuse Hülle um den Kern des Kometen, die man Koma nennt, und ein ausgeprägter Schweif. Beobachtungen von SPECULOOS zeigen, dass sich der Schweif von C/2016 R2 (PANSTARRS) innerhalb einer Nacht drastisch verändern kann, was zu einer stark variierenden Bildreihe führt. Das hier gezeigte Bild und die zugehörigen Bilder im Zeitrafferfilm wurden am 18. Januar 2018 während der Testphase des SPECULOOS-Teleskops Callisto aufgenommen, zu einer Zeit, als der Komet 2,85 AE von der Sonne entfernt war (1 AE entspricht der Entfernung Erde-Sonne) und auf dem Weg ins Innere des Sonnensystems war.

Der Komet ist deshalb besonders interessant, da seltene Verbindungen und Moleküle in seiner Koma gefunden wurden: Kohlenmonoxid und ionisierter Stickstoff. Diese verleihen dem Kometen ausgeprägte Emissionslinien, weshalb er auch den Spitznamen „der blaue Komet“ erhielt. Dieser scheue Komet umkreist die Sonne nur einmal in 20.000 Jahren. Sein letzter Vorbeiflug an der Sonne war im Mai 2018. Das Bild wurde mit einer langen Belichtungszeit aufgenommen, während der das Teleskop der Bewegung des Kometen folgte: Die hellen Lichtstreifen im Hintergrund sind weit entfernte Sterne. Doch der Komet und seine gasförmige Koma sind scharf abgebildet, ein Zeichen für die hervorragende Nachführleistung von SPECULOOS.

Link:

• Zeitrafferfilm der Veränderung des Kometenschweifs

Comet 46P/Wirtanen and a commercial plane over Paranal Observatory.

Comet 46P/Wirtanen and a commercial plane over Paranal Observatory.

The Moon appears more red/orange as it first begins to rise due to scattering of light by Earths atmosphere. When we view the Moon on the horizon, the moonlight has to pass through a greater distance of the atmosphere to our eyes. By this time light on the blue end of the visible spectrum has been scattered away thus we only see the longer wavelengths of visible light, yellow, orange or red. When the Moon is directly overhead (as is pictured here in the last frame), the moonlight has to pass through less of the atmosphere and thus appears as usual.

Sunset at La Silla. La Silla Observatory was ESO’s first observatory in Chile and is located in the remote Atacama desert of northern Chile. In the picture a green flash can be seen.

Dieses Bild zeigt den Bereich des Himmels, in der der Asteroid 2006 QV89 bei einem Kollisionskurs mit der Erde im Jahr 2019 zu sehen gewesen wäre. Die drei roten Kreuze zeigen die spezifischen Stellen, an denen der Asteroid als eine einzelner großer schwarzer Punkt hätte erscheinen müssen, wenn er sich auf Kollisionskurs befände. Es wurde aber nichts beobachtet.

Selbst wenn der Asteroid mit nur wenigen Metern Durchmesser kleiner als erwartet wäre, wäre er im Bild zu sehen gewesen. Wäre er noch kleiner, so dass das VLT ihn nicht hätte nachweisen können, wäre er als harmlos anzusehen, da jeder Asteroid dieser Größe in der Erdatmosphäre verglühen würde.

Original high-resolution image of the 1919 solar eclipse before the digital restoration. Funding for this project was provided Klaus Tschira Foundation under grant No. 00.071.2005.

The highest resolution image of the 1919 solar eclipse is also available.

This image shows the Sun through various phases of the total solar eclipse visible over ESO's La Silla Observatory on 2 July 2019. It was taken using an H-alpha filter. The eclipse lasted roughly two and a half hours, with almost two minutes of totality at 20:39 UT, and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

This image combines a photograph from La Silla in visible light, with ultraviolet data from SOHO's EIT instruments (284 Å) and four filters from Solar Dynamics Observatory's AIA instrument (193 Å, 211 Å, 304 Å and 171 Å).

The combination of these different data all captured close to totality shows the complexity of the solar magnetic field during the eclipse. A large, but not powerful active region can be seen in the middle of the solar disk. The poles of the Sun are relatively dark and with more outflow of ions.

On 2 July 2019 a total solar eclipse passed over ESO’s La Silla Observatory in Chile. The eclipse lasted roughly two and a half hours, with almost two minutes of totality at 20:39 UT, and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

Am 2. Juli 2019 verlief eine totale Sonnenfinsternis über dem ESO-Observatorium La Silla in Chile. Dieses Bild zeigt die Sonne, die während der Totalität vollständig vom Mond bedeckt ist, sowie die Sonnenkorona oder die Atmosphäre der Sonne. Während die Totalität nur etwa zwei Minuten dauerte, erstreckte sich die Finsternis insgesamt über zwei Stunden und war über ein schmales Band von Chile und Argentinien sichtbar. Um dieses seltene Ereignis zu feiern, lud die ESO 1000 Personen, darunter Würdenträger, Schulkinder, Medien, Forscher und die breite Öffentlichkeit, ein, an die Sternwarte zu kommen, um die Sonnenfinsternis von diesem einzigartigen Ort aus zu beobachten.

On 2 July 2019 a total solar eclipse passed over ESO’s La Silla Observatory in Chile. The eclipse lasted roughly two and a half hours, with almost two minutes of totality at 20:39 UT, and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

On 2 July 2019 a total solar eclipse passed over ESO’s La Silla Observatory in Chile. The eclipse lasted roughly two and a half hours, with almost two minutes of totality at 20:39 UT, and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

On 2 July 2019, a total solar eclipse passed over ESO’s La Silla Observatory in Chile. This image shows the Sun completely covered by the Moon during totality, revealing the solar corona, or the Sun's atmosphere. While totality only lasted about two minutes, the eclipse overall lasted over two hours and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

Am 2. Juli 2019 verlief eine totale Sonnenfinsternis über dem ESO-Observatorium La Silla in Chile. Die Sonnenfinsternis dauerte etwa zweieinhalb Stunden, mit einer Totalität von fast zwei Minuten um 20:39 UT (22:39 MESZ), und war über ein schmales Band von Chile und Argentinien sichtbar. Um dieses seltene Ereignis zu feiern, lud die ESO 1000 Personen, darunter Würdenträger, Schulkinder, Medien, Forscher und die breite Öffentlichkeit ein, an die Sternwarte zu kommen, um die Sonnenfinsternis von diesem einzigartigen Ort aus zu beobachten.

This image was taken by the ESA–CESAR team of scientists at the total solar eclipse visible from ESO's La Silla Observatory on 2 July 2019. It was made by combining multiple polarised images of the solar corona during totality to bring out the details in its structure.

This image of the solar corona was taken by an ESA–CESAR team of scientists during the total solar eclipse visible from ESO's La Silla Observatory on 2 July 2019. It clearly shows bright red prominences — places where loops of glowing plasma flow up from the Sun's surface. The path of this plasma, composed of hydrogen and helium, is probably determined by the Sun's magnetic fields, which can twist and tangle in strange ways. We know that prominences can persist for weeks or even months, but we don't fully understand why they exist or what their internal dynamics are. This is why continuing research into the Sun's complex atmosphere is important, much of which can only be done during total solar eclipses.

This image highlights Baily's Beads, a feature of total solar eclipses that are visible at the very beginning and the very end of totality. It's composed of a series of images taken during a total solar eclipse visible from ESO's La Silla Observatory on 2 July 2019.

Baily's Beads are caused by the Moon's mountains, valleys, and craters. These surface features create an uneven edge of the Moon, where small "beads" of sunlight still shine through the lowest parts for a few moments after the rest of the Sun is covered. In this picture, multiple images taken in quick succession show that the beads disappear and appear in stages, with only the very deepest valley and craters allowing the sunlight to shine through closest to totality. The phenomenon is named after Francis Baily, a British astronomer whose observations in the early 1800s first widely publicised their existence. Appropriately, 2019 was the 245th anniversary of Baily's birth.

An image of the Sun during the total solar eclipse visible from ESO's La Silla Observatory on 2 July 2019 at the moment when most of its face is occulted by the moon. The eclipse lasted roughly two and a half hours, with almost two minutes of totality, and was visible across a narrow band of Chile and Argentina. To celebrate this rare event ESO invited 1000 people, including dignitaries, school children, the media, researchers, and the general public, to come to the Observatory to watch the eclipse from this unique location.

This image combines two different sources to create a fairly complete view of the Sun's corona rarely available to researchers, taken during the total solar eclipse visible from Chile on 2 July 2019. The outer blue portion of the image was taken by the LASCO instrument on the SOHO spacecraft during the eclipse. SOHO can observe the solar atmosphere all of the time by using an occulting disc to cover the Sun, in effect creating artificial eclipses from the spacecraft's point of view. However, this occulting disc has to be larger than the Sun in order to ensure it remains covered at all times, leaving an empty doughnut hole in the middle of all SOHO's images of the corona.

The centre of that doughnut hole can only be filled in during a total solar eclipse. Because the Moon covers the Sun much more precisely than SOHO does it reveals the inner corona SOHO cannot observe. In this case, the image was taken from ESO's La Silla Observatory, and the intricate but normally invisible inner corona is visible in exquisite detail. Combining it with a SOHO image taken at the same time gives the rare opportunity to view both the inner and outer corona together — providing a unique window into our active star.

This image is a deep high dynamic range composite of series of different exposures that reveals the finest details in solar corona visible during the total solar eclipse on 2 July 2019, captured from ESO La Silla Observatory. The solar corona is a plasma of free electrons scattering the Sun's light. The electrons in it are affected by the star's magnetic field, so their shape reveals the fields' contours. During this eclipse, the corona had the dipole character typical during a deep solar minimum. The thin streamers sticking out indicate the two poles, while the Sun's equator is highlighted by long streamers and magnetic loops. In reality, the corona extends much further than the edges of this image, as can be seen in these images of the same eclipse, created by combining this image with data from the NASA–ESA SOHO spacecraft.

This image combines two different sources to create fairly complete view of the Sun's corona rarely available to researchers, taken during the total solar eclipse visible from Chile on 2 July 2019. The outer blue portion of the image was taken by the LASCO instrument on the SOHO spacecraft during the eclipse. SOHO can observe the solar atmosphere all of the time by using an occulting disc to cover the Sun, in effect creating artificial eclipses from the spacecraft's point of view. However, this occulting disc has to be larger than the Sun in order to ensure it remains covered at all times, leaving an empty doughnut hole in the middle of all SOHO's images of the corona.

The centre of that doughnut hole can only be filled in during a total solar eclipse. Because the Moon covers the Sun much more precisely than SOHO does it reveals the inner corona SOHO cannot observe. In this case, the image was taken from ESO's La Silla Observatory, and the intricate but normally invisible inner corona is visible in exquisite detail. Combining it with a SOHO image taken at the same time gives the rare opportunity to view both the inner and outer corona together — providing a unique window into our active star.