Ugh, fire reestablishing on #MountWilson again, roughly 500 ft NNW of the observatory. #BobcatFire It's rapidly approaching the repeater towers. Expect an aggressive aerial response shortly.. #BobcatFire

Not loving this flare-up east of @MtWilsonObs. #BobcatFire Phos-Chek drop east of @MtWilsonObs #BobcatFire

There are currently zero air assets over #BobcatFire, although it looks like this guy might be waiting for smoke to clear or looking for an entry point west of Santa Anita Cyn. Anyone on the ground in #SierraMadre or #Pasadena have eyes on this one?
via @flightradar24 Looks like they aborted, I’m guessing due to poor visibility. Haven’t heard any mention of it on the radio yet.

I built a makeshift air purifier with an HVAC filter & fan. It’s making a big difference, reducing smoke smell & irritation. I’m measuring 50% reduction in particulates after 30 mins, reducing indoor AQI from “very unhealthy” classification to “unhealthy for sensitive groups”. Running ~1hr on/off cycles to compare air quality with/without. Just started 2nd on cycle. I’ll post legit plots later & a writeup on @hackaday.io, but for now, here’s a screenshot of my live preview, showing 2.5um particle counts in ug/m3, with ~50% dip during first on-period.

Feels like 50/50 odds you’ll see a horrific accident if you head up Angeles Crest on any given Sat or Sun in the summer. So many car/moto clubs & daredevils getting their kicks.

2 wks ago, I saved a motorcyclist’s life after a reckless BMW coupe ran him off the road. (thread)

https://twitter.com/MontroseSAR/status/1295179707525156865

I myself came around a blind corner a little fast and had to jam my breaks to avoid hitting the motorcyclist as he was picking his bike up from my lane. I reversed out of the blind curve and put my flashers on to block traffic at the start of the curve.

Went out to shoot Mars again last night but it turned into a full-blown Grand Tour. Imaged every planet except Mercury! Plus a few moons I didn’t expect to find.

Starting in the outer solar system, we find gas giants Jupiter, Saturn + Tethys, Uranus, & Neptune + Triton. Moving inward, here’s an animated view of Mars, rotating about 7 degrees over a span of 30 minutes. By the way, Earth and Mars rotate at similar rates, with Earth spinning about 3% faster.

#cometNEOWISE, viewed from @Angeles_NF this morning. Was hoping my fast 10” f/3.9 Newtonian would pull out more faint detail in the tail, but it was swamped by pre-dawn light. #cometNEOWISE is getting very close to the sun now. Hope this thing lights up on its way out next week. I’ll go wide field next time. 🔭💫

Gonna work some birds this weekend! 📡 🛰 @arrl #FieldDay #CQCQCQ NG6F @arrowantenna #fieldday2020 equipment check. NG6F, 1B LAX

The fy2021 NASA budget proposal carves out a healthy slice for the 2nd of 3 missions comprising Mars Sample Return. This mission will gather samples pre-packaged by the 1st MSR mission, M2020, & will loft them into orbit for a 3rd mission to pick up later. latimes.com/science/story/… My first job at JPL, in 2010, was as a systems engineer for the Mars Program’s Advanced Studies office. My contributions to MSR included leading several “Fetch Rover” concepts and evaluating industry proposals for the Mars Ascent Vehicle (“MAV”).

A year and a half after concluding my 6-yr stint on the MSL project, I finally got around to compiling my personal photo album. The book is not for sale, but here are some highlights to give you a feel for what it's like to operate a Mars rover. (thread) A good way to learn how to operate this 1-ton space robot is to spend some time in the Mars Yard. I spent about 700 hours here over the years, sometimes driving but mostly working on new drilling techniques. Sometimes funny people come to hang out, like Mr. @SethGreen here.

#Tornado near Chowchilla 30 mins ago! #CAWX @NWSSacramento, we saw small debris ball on the ground for just a couple seconds. Have footage but can’t discern touchdown rope out on the ground, shot by @StephenAsAHuman

Was in the water at a secret surf spot on SC Island, couple miles from the epicenter, when this hit. Felt mild, just a thump sound and subtle vibration through the water, but it triggered hundreds of small rock slides and dust clouds from cliffs behind us apple.news/AhFt1AymvREGvW… and thousands of bait fish jumped out of the water all around me immediately after the thump

It’s happening! First drilling attempt since Curiosity’s drill feed mechanism fell sick in Dec 2016. Engineering team briefly revived the feed just long enough to extend the bit past the stabilizers, making possible this method we hoped we would never need.👇

https://twitter.com/spacegirlkim/status/968160974032130049

This will be Curiosity’s first attempt at drilling using only 1 of 3 actuators that are normally required for drilling. Feed is virtually inoperable. Percussion is sick too but it’s haning in there; we just don’t know yet how to use it without feed and stabilizers.

Tango delta nominal! First drill contact since drill feed failed in Dec 2016. Precursor for feed-extended drilling go.nasa.gov/2gGvSfr We found in testing on earth that we need to sense and react to side loads during feed-extd drilling to avoid jamming the bit

Engineers testing drill percussion without stabilizers on Earth to prove hardware safety for @MarsCuriosity on Mars @MarsCuriosity Test went well and we'll soon greenlight percussive drilling dev. Non-percussive drilling dev is much further ahead but still has challenges