Saturn visible behind Lutetia during flyby

Hey, this is pretty cool; I'm always a fan of planetary conjunctions.

Saturn was visible in a few of the images of Lutetia taken by Rosetta as it passed by!

Fly-by of Lutetia is a success

Another successful asteroid fly-by!
http://www.planetary.org/blog/article/00002577/

Old Mars photos from 2003: No, it's not going to be big in August.

Inspired by a query regarding the false meme going around about Mars, I took a look at some images I took of Mars during it's big opposition in 2003. That was a great opposition. Here's a couple of those images. The first one is a single image without manipulation, the second and third are Registax processed images from videos, and the last is one of those videos.
Mars at the moment is not approaching one of those awesome 17 year oppositions like 2003 or 1988. It's just fading away from its January opposition and currently visible in Leo in the evening.

nose grease

In my high school days I had a part-time job at a professional photo lab / studio called "Phillips' Photo Lab". I was hired as the black and white darkroom guy--I manually processed film, printed custom prints, shot copy negatives, and cleaned the color film and print processors. Later I branched into running the shop on Saturdays and once, just once, did a color print job.

I learned a lot from the pros whose lifeblood was photography: the tips and techniques that make life easier.

One of the things that I would not had believed unless I had personally experienced it was the magic of nose grease. The skin on the nose and to a lesser extent the neck near the back of the ears produces a hydrocarbon of about C30H50 called squalene. The only reason this is important was squalene had the same index of refraction as the gelatin used in photographic processes and hence could be used to fill in scratches on negatives and slides. You would acquire some nose grease, rub it gently into the scratch, and rewash the negative. Nearly as good as new, and it allowed prints and reproductions from otherwise damaged negatives.

This particular example is this blog's first mention of a principle I like to call "matching impedances". In the world there are a lot of interesting issues that in the end are solved or mitigated by taking two different systems and making them the same at the point they meet. In electronics, to maximize power transfer between two parts of a circuit, you match their electrical impedances (which is a function of their resistance at all frequencies).

You have encountered this when setting up a TV or stereo system; the speakers have an impedance rating on them, usually 8ohms for a home stereo and 4 for car audio. Your amplifier speaker outputs need to be designed to deal with a particular impedance; stick a 4ohm speaker on an amp designed for 8 and you might mess things up. On your TVs there used to be two terminals for antennas--one was coaxial and had an impedance of 75ohms and is now the de facto standard, and the other was two screws that had an impedance of 300ohms. To get the most signal you'd want all the impedances to match up: the TV, the cable, and the antenna. If they didn't, part of the precious signal would be reflected back towards the antenna and lost. For converting the impedances to match a little transformer was used, of which there may be a hundred million hiding behind the TVs of the world. Again, here the principle of matching the impedances came into play.

In the optical world reflections occur at surfaces that have differing indexes of refraction. The bigger the difference the higher the reflection ( I think it's a square of (n-n2/n+n2). For solar panels, for instance, the high index of refraction of silicon (4) compared to air (1) makes something like 50% of the incident light reflect off unless you use anti-reflective coatings to improve it. So even for something like a renewable energy resource you have to consider such details.

I use nose grease (n=1.45) to also try to fill in scratches in CDs/DVDs (made of polycarbonate, n=1.58). It's not perfect, but sometimes it makes it playable.

So, in the end: Match your impedances!

Hayabusa coming home

An amazing comeback for the little falcon that could--


Credit: ISAS / JAXA / Øyvind Guldbrandsen / Planetary Society Blog

The Japanese spacecraft Hayabusa will be returning to Earth with perhaps a sample of the asteroid Itokawa in just four days. This spacecraft has had as many setbacks in the seven years it's been running as you can have without losing the craft completely. When they released the data archive in 2007 I made a color image of Earth made by Hayabusa during a flyby and some more surface close-ups here.

Visible Jovian impact

Link and run: http://arstechnica.com/science/news/2010/06/breaking-news-jupiter-hit-by-yet-another-impactor.ars

Eyjafjallajökull eruption: webcam at midnight

It's midnight in Iceland and nearly midsummer with a volcano erupting, what do you do? Hang out in front of the thermal camera.

Eyjafjallajökull eruption: webcams

There are several webcams watching the Ejyafjallajökull eruption; and at this time of year the plume is illuminated all the short night long. I watched the sunset at 10:30PM and am now watching the sun rise at 4:30AM. The eruption continues through the Arctic summer night.

http://eldgos.mila.is/english/eyjafjallajokull-fra-hvolsvelli/



http://eldgos.mila.is/english/eyjafjallajokull-fra-thorolfsfelli/
This one is closer and has a thermal IR camera as well; but it's also more often obscured by ash and fog.

Jupiter's SEB has gone pale

Jupiter's South Equatorial Belt, normally a brown-red, has gone as pale as the cream white zones surrounding it. Check out the report with images at the Planetary Society Blog: http://networkedblogs.com/3Jnoh. This is one of those things that happens every 5-10 years or so.

ISS passes for the next ten days for Chicago

http://www.heavens-above.com/PassSummary.aspx?satid=25544&lat=41.781312&lng=-87.605097&loc=Chicago&alt=0&tz=CST

Floyd Dominy

http://www.hcn.org/hcn/wotr/floyd-dominy-the-colossus-of-dams-dies-at-100

The view from Thorvaldseyri of the Eyjafjallajökull eruption

The view from Thorvaldseyri of Eyjafjallajökull

You can just pick out the ice sheet from underneath the clouds.


Compare this with the view the farmer had recently:
http://icelandreview.com/icelandreview/upload/images/news/almennt/thorvaldseyri_olafur_eggertsson.jpg

From:
http://icelandreview.com/icelandreview/daily_news/?cat_id=16539&ew_0_a_id=361234

Eyjafjallajökull eruption: gorgeous video

The NY Times Lede blog has linked to BBC Channel 4 video of the eruption. From the look of it, the videographer had one of the many excursion drivers take them up Thórsmörk (or Þórsmörk) valley on the north side up high enough to look at the eruption without dealing with the jokulhaup (or glacial flood) in the river. If you have ADD you will miss the active sub-Plinian eruption and great lightning in latter half of the video.

UPDATE: the waterfall at the beginning is Seljalandsfoss. I have a photo of it here: http://www.flickr.com/photos/dwarmstr/4532063271/.





EDIT: calling it sub-Plinian.

Eyjafjallajökull eruption: planes vs. volcano

An interesting data point about the Eyjafjallajökull eruption: the disruption of the European aviation market reduces the CO2 output by an order of magnitude more than the CO2 released by the volcano itself,

Source: http://www.informationisbeautiful.net/2010/planes-or-volcano/

Moments in spaceflight

Soichi Noguchi captures a poignant moment as the Shuttle leaves the International Space Station. Click to enlarge to a higher quality image.