25 May 2024 - Mission Day: 10403 - DOY: 146
Pick of The Week

The Great "Birthday Comet" of 2011
Comet Lovejoy Grazes the Sun (and survives)

Last update: 16 Dec 2011, 11:16 EST

Comet Lovejoy has entered the LASCO C3 field of view early on December 14 (look for it here), entering from the south.

Comet Lovejoy skimmed across the Sun's edge about 140,000 km above the surface late Dec. 15 and early Dec. 16, 2011, furiously brightening and vaporizing as it approached the Sun. It is the brightest sungrazing comet that SOHO has ever seen, with a nucleus about twice as wide as a football field. It unexpectedly survived the pass and cruised out from behind the Sun some hours later. Comets are ancient balls of dust and ice. Solar Dynamics Observatory (SDO) also recorded close-up observations that can be seen here: here.

* NASA Science News Story: Comet Lovejoy Plunges into the Sun and Survives


Hi-res TIF image (1.2M)

Quicktime: Large (5.8M), Small (1.3M).
MPEG: MP4 (2.1M) and M4V (850K)

December 16, 12:00UT: Comet Lovejoy survives!!! Somehow it survived being immersed in the several million-degree solar corona for almost an hour and has now re-emerged back into the views of the LASCO and SECCHI coronagraphs, almost as bright as before! The only noteable exception is that it appears to have lost its tail, as you can see in the image.

December 15, 22:50UT: Comet Lovejoy racing through the LASCO C2 field of view. Notice the faint ion tail: that's the first time we've seen on a Kreutz-comet in LASCO! (Click on the image to see a larger movie)

December 15, 22:50UT


Comet Lovejoy in C3 and AIA 304 from 9:30 Dec 14 to 9:30 Dec. 15.
Movie (QT, 1.7MB)

Dec 14, 2011 15:00UT - Early this morning C/2011 W3 (Lovejoy) made its debut in the LASCO C3 camera (click on the image for higher resolution). It seems to be the brightest sungrazing comet that SOHO has ever seen.

Movie of the comet as of December 12, 2011 17:00UT.

First full-resolution (cropped and scaled x2) sequence of Comet Lovejoy.
From STEREO/SECCHI HI-1B images.

Movies provided by Karl Battams (LASCO/NRL).
For more information please also visit the LASCO Sungrazer site.

Below, a graph with the expected trajectory as the comet will be close to the Sun.

Calculations and graph, provided by William Thompson (STEREO Science Center Chief Observer, GSFC).

Caption: Plot shows the expected trajectory of the comet close to the Sun. It passes behind the Sun as seen from Earth.

Image Credit: Rob Kaufman (Bright, Victoria, Australia)

SOHO's 16th Birthday gift is on it's way, and the tracking number states delivery by midnight on December 15th!

On December 2nd, 2011, newly discovered Kreutz-group comet C/2011 W3 (Lovejoy) was announced. SOHO discovers these objects on average every three days, but this one is different... it was found from a ground based telescope, and marks the first such discovery in over 40yrs. It also marks a significant achievement for Australian astronomer Terry Lovejoy, who as an early pioneer of discovering SOHO comets over the internet, can now claim to be the first person to discover a Sungrazer from both ground and space-based telescopes!

Traditionally, and with little exception, ground-discovered Kreutz-group comets have gotten bright. Very bright! In 1965, Kreutz-comet Ikeya-Seki was so bright, it could be seen by the naked eye by blocking the Sun out with your hand. We do not expect C/2011 W3 to get this bright, so reserve your seat next to your computer and stay tuned to the SOHO, STEREO and Sungrazer websites as we prepare for this rare and potentially spectacular object to enter our cameras around Dec 12, meeting its fiery demise late on Dec 15.

We will have more information on this site over the coming week. In the meantime, updates will occasionally be posted at the Sungrazer site.

Stay tuned!


SOHO began its Weekly Pick some time after sending a weekly image or video clip to the American Museum of Natural History (Rose Center) in New York City. There, the SOHO Weekly Pick is displayed with some annotations on a large plasma display.

If your institution would also like to receive the same Weekly Pick from us for display (usually in Photoshop or QuickTime format), please send your inquiry to steele.hill@gsfc.nasa.gov.


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Last modification: July 27, 2020

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