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Moon shadow, moon shadow.
Fri 2015-03-20 21:28  

cassini sketch hubble heritage IRTF hubble hangout Image Map !! from image-maps.com

A lot of cool things have been going on lately with solar eclipses on Jupiter, or "shadow transits." Giovanni Cassini was the first to actually observe one of these events (upper left), back in the 1600s at the dawn of the telescopic era of astronomy. He used his observations to implement one of Galileo's ideas: to use the timing of mutual events (eclipses and transits) as a type of absolute clock that could work anywhere on the Earth, back before atomic clocks or quartz oscillators were available.

These events can be visually stunning, as the Hubble images of a rare triple-transit (lower left) show. Last month, I joined some Space Telescope Science Institute folks and Scott Lewis from knowthecosmos.com for a 1-hour chat about the spectacular Hubble imaging data (lower right). It was a good time, and Susana Deutua from the Institute showed off her Galileoscope, a replica of the telescope used by Galileo himself.

Just this week, right in the middle of the LPSC meeting, I participated in a super exciting remote-observing session at the IRTF telescope on Mauna Kea. The PI of the observing program, Gordy Bjoraker, came up with a brilliant way to use shadow transits. Our goal was to measure infrared spectra, made up of thermal emission from the deeper atmosphere. We're using the data to figure out just how deep Jupiter's water clouds lie. However, near Jupiter's equator, things get tricky — thick clouds there also reflect sunlight that is still weakly present at 5-μm wavelengths. Gordy wanted to get a spectrum of just the thermal emission, without that pesky reflected sunlight. Io to the rescue! Io's shadow conveniently blocked most of the sunlight from the clouds in a little spot (screenshot by Tilak Hewagama at upper right), allowing us to take a pure thermal spectrum within the shadow.

Analysis of these fresh data will take a while, but it's definitely worth the wait. We'll be sure to have results before the Juno spacecraft gets to Jupiter and conducts its highly complementary observations.


Giant storms on giant planets
Fri 2014-10-03 10:54  

When Voyager passed by Uranus in 1986, none of this was going on. Of course, the "blue" image above is false color, applied to infrared images of Uranus from the Keck Observatory. These storms are a lot more dramatic in the infrared. But still, seven years after equinox in Uranus' 84-year annual cycle, storm activity seems to be picking up.

The storms themselves, at least visually, look similar to storms on Jupiter and Saturn, as seen in the infrared. These storms are rare on any of the giant planets, but there are a lot of questions about them. How much of the planets' internal heat do these superstorms carry? How often do they happen? Are they part of long term cycles?

This is what I love about studying the solar system. It never gets old. Things change and evolve over time.


LPSC Megablog.
Thu 2013-03-21 6:05pm in TX  

Microblogging is really big at LPSC. I'm not a microblogger, or any kind of blogger really. I worry that as technology advances, and attention spans shrink, I am developing a mental disability. Short attention spans used to be characteristic of an attention deficit disorder. But now short attention spans are normal, and those who prefer to devote attention to things for longer amounts of time are the anomalous ones. So I think I have Attention Excess Disorder. Pharmaceutical companies, please develop some medicine for me so I can microblog.

I had lunch today with Max Mutchler from STScI (a collaborator on Planet Pipeline and Planet Investigators), and I was amazed to find out that he's a kidney donor just like me! I'm not shocked to meet a kidney donor. But to collaborate with one for more than three years, only to find this out halfway through lunch, was quite a shock. We talked about how we were affected by the situations that made our operations necessary, rather than the operations themselves.

I forgot to ask Max whether he was ever told, as I was recently by a friend, "You? You're the LAST person I would expect to be a kidney donor!"

On my quest for free stuff in the exhibitors section, I came across edible rocks courtesy of the CPSX booth (which they bought from a store nearby). Pictured are a black one and a yellow one. They look exactly like rocks, but they're chocolate! I'm looking around for Laurie Leshin, because she said during her talk that Curiosity finds 150-μm grains to be the "yummiest" dirt; but now, the rover is not the only one who eats rocks!


Using pine and bmail.
Sat 2013-02-09 18:02  

I hate change! That's why I still use pine. My nephew saw my screen last night and was like "Wow, look at all those lines of code!" It was just pine. Nobody even knows what it is. But for the few that still use it, and who want to be able to use it with Berkeley's new bMail service, here's how to set it up.

  1. Follow step 1 and 2 (only) here, to set bmail configuration options and to generate a google key that you need for login: http://kb.berkeley.edu/campus-shared-services/page.php?id=26754.
  2. In pine, go to the setup screen (M-S-C keys). Find and set the following config lines:
         SMTP Server (for sending) = smtp.gmail.com/ssl/user=username@berkeley.edu
         Inbox Path = {imap.gmail.com/ssl/user=username@berkeley.edu}inbox
  3. Now when you use pine, it will prompt you for your ugly-looking google key when you try to use email. This next step is optional, but it will allow pine to retain the key so you don't have to keep entering it:
    • Create your pine-password storage file, if it doesn't already exist. At the command line, type touch ~/pine.pwd. The file name can be anything, but this is the name they used on the page that showed me how to do this. The file wil contain your google key, but encrypted.
    • From now on, start pine with the right option to look for the password file. You can either type the option every time, or include an alias in your startup file. I only know how to do this for the csh/tcsh shells: cat alias 'pinemail pine -passfile ~/pine.pwd' > .cshrc. For other shells, you would probably need to change the syntax for the alias command, and/or store the command in another file (like profile.bash instead of .cshrc or something).
    • Now start pine, with the -passfile option. When it asks for a password, enter the google key from step 1. Pine should then store it in the pine.pwd file, so you never have to ener it again.

Thanks Google! That was much easier than trying to get pine to work with Microsoft Exchange.


They don't make school lunch the way they used to.
Thu 2012-11-08 16:28  

I had a great time this week, speaking to 311 students at South Pointe Middle School in Diamond Bar on Tuesday (thanks, Kellie Muragishi!), and 36 students in the Robotics Magnet Class at Audubon Middle School in Crenshaw yesterday (thanks, Eric Yu!).

JPL's Mars office set me up with a rover model and a full size model rover wheel, and Scott gave me some NASA "meatball" stickers to hand out. These were great bribes to encourage the students to ask questions at the end. Some highlights:

  • I got more questions about my inspiration and enjoyment of work, than about how much money I make. But they still did ask.
  • When I asked what social/environmental issue relates to CO2 in the atmosphere, none of the students in Diamond Bar guessed that I was thinking climate change. Several of the Crenshaw students almost immediately knew what I was fishing for.
  • School lunches have changed since I was little... similar to how airplane food changed. They used to be little cooked meals from the school kitchen, but now the lunches are pre-packaged corporate food. I had Subway sandwich at South Pointe, and another option was a pita-pack encased in a black plastic tub with a plastic sheet that you have to peel back to get to the food. Maybe I didn't get in the right line, because another guy in the Faculty Lounge was eating a school lunch in a small white Chinese takeout box.


Flash news.
Tue 2012-09-11 12:34  

What an exciting night. Or day. Or sol?

I slept in yesterday, missing some key emails, and showed up to work "early" for my shift doing MSL operations work (at 8pm). That's when I found out there was another Jupiter fireball. This one was discovered by Dan Petersen in Wisconsin by visual observation, and confirmed when George Hall went back and found the flash in his archived video.

Being simultaneously pulled to work on Mars and Jupiter made me almost believe in astrology. I definitely felt that the planets were controlling my life.

About the image: My lightcurve has a large uncertainty, but is sufficient to predict that this event is too small to create a visible impact scar. George Hall was kind enough to share his video data for this analysis. The inset image consists of 22 frames of George's data, stacked by Ricardo Hueso and treated with a mild high-pass filter. Light curve data points are based on radial brightness curves, extrapolated to compensated for saturated pixels in the original data.

More detailed reports include:


Time Lapse Saturn/Jupiter Video: "Outer Space."
Wed 2012-05-02 12:09  

I just found out about this awesome video by Sander van den Berg, using Voyager and Cassini imaging data. If you're like me, you've seen some of the videos in this compilation, but this is a really breathtaking new way to absorb them. A lot of physics, some understood and some not, is captured in this 1:52 piece.


Space Senator.
Thu 2012-04-12 14:01  

I just went to browse MAST, formerly the Multimission Archive at STScI, and found out that it's been renamed. It's still MAST, but now it stands for the Mikulski Archive for Space Telescopes.

Senator Barbara Mikulski was honored for becoming the longest-serving woman in U.S. Congressional history, and also for being a great defender of space exploration and research. There are nice writeups about MAST and Sen. Mikulski on the about MAST page and a Hubble press release. Although some NASA advocates focus their support on the manned space program with its associated defense contractor expenditures, Senator Mikulski's record shows support for the kind of stuff I do: science. I'm proud that they renamed the archive after her.


Space Ronin.
Tue 2012-02-28 12:20  

My career is not not going quite the way I thought it would, back when I was 18. Shouldn't I have a faculty job by now? Or a civil servant position at NASA?

These days, many people adopt different paths. We branch out, or we work at scientist farms, where top-quality researchers can sustain themselves on grants. So I'm starting a new (part-time) Visiting Scientist gig at University of Michigan, following on an awesome Visiting Scientist stint at Space Telescope in 2009-2010. At Michigan I'll be working with the SAM instrument on the Curiosity rover.

Although a part-time visiting scientist arrangement is odd, and inconvenient... I don't think it's extremely unusual these days. I'm a Space Ronin; I have no tenure and I work here and there. I'm well regarded internationally in my field, but just without the job to match. I console myself in the quote usually found on the whiteboard behind the bar at Tommy's: "IF YOU LIVE IN S.F. PLEASE REMEMBER HOW LUCKY YOU ARE."