Astro Bob A look at celestial happenings in the Northland and beyond Bob King View my profile Click here to view previous posts or additional resources

Jupiter flash leaves no trace

In this photo taken in visible light on June 7, the Hubble scope wasn't able to see any evidence for dark impact spots in the wake of the meteor strike on June 3. The circled area is where the flash was seen. Credit: NASA/ESA

Whatever it was, Hubble can't see it. You might recall back on June 3 that Australian observer Anthony Wesley spotted a pinpoint flash of light in Jupiter's South Equatorial Belt (right). It was probably a comet or asteroid fragment burning up in the planet's atmosphere creating a fireball just like the ones we occasionally see in our skies. For days following the impact, amateur astronomers around the planet were up at dawn hoping to see black sooty clouds in Jupiter's cloudtops in the fireball's wake. Nothing ever showed.

You'd think that if any telescope could succeed at seeing at finding the spotty after-effects of the impact, Hubble would be up to the job. On June 7, astronomers trained the Hubble Space Telescope on the giant planet and took closeup photos of the region in visible light as well as ultraviolet and infrared. Not a trace of debris or dark cloud was found:

"This means that the object didn’t descend beneath the clouds and explode as a fireball. If it did, dark sooty blast debris would have been ejected and would have rained down onto the cloud tops, and the impact site would have appeared dark in the ultraviolet and visible images due to debris from an explosion," says team member Heidi Hammel of the Space Science Institute in Boulder, Colo. “We see no feature that has those distinguishing characteristics in the known vicinity of the impact, suggesting there was no major explosion and fireball.”

So what happened exactly? The 2-second-long flash Wesley saw was real, since it was confirmed by another expert Jupiter observer, Christopher Go, of the Philippines and recorded on video. No doubt it was a piece of an asteroid or comet burning up in Jupiter's atmosphere, but scientists like Hammel think it was too small to penetrate further down into the planet's atmosphere and create the dark plumes and spots like those seen in the 1994 and 2009 impacts. Wesley saw a Jovian meteor, and they may be fairly common, but because most flashes are so brief, they're almost never witnessed. Who will see the next?

Two pictures of Jupiter taken by the Hubble Space Telescope almost a year apart show well how much the planet's south equatorial belt has faded. Scientists think it's hidden beneath a high altitude layer of white ammonia clouds. The clouds are expected to clear in several months beginning with a series of dark spots similar to the ones in the zone below the faded belt. Credit: NASA, ESA, M.H. Wong, H.B. Hammel, A.A. Simon-Miller, and the Jupiter Impact Science Team

Two fishermen hope for a bite on Finlander Bay on Island Lake north of Duluth last night. Photo: Bob King

Summer is here officially or not. The air was calm and humid last night and still no bugs. Sam Cook, the outdoors writer for the Duluth News Tribune, and I went out to Island Lake to look for people fishing for a story he's working on for this weekend. Around 8 o'clock, as evening gathered under low clouds, we came across two guys sitting on pickle pails fishing on the edge of a vast expanse of calm, reflective water. The sky looked amazing on the water and these guys, along with Sam and I briefly, had a piece of Eden to ourselves. Later at home I took a walk as the clouds departed and the moon broke through in the west. The Summer Triangle of Vega, Deneb and Altair was up even before the sky got dark. Fireflies were a pleasant distraction from the stars.

I sometimes compare seasons and like a kid wonder which is my favorite, but each time I get lost in the current one, and the question never gets answered.

Posted by: rking@duluthnews.com on 6/17/2010 at 8:41 AM | Comments (0) | Permalink | Edit

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