Extragalactic Astronomy and Spacebased Imaging

Tucson, AZ
Joined November 2014
New Horizons is so far away that the nearest stars have shifted markedly from where we see them on Earth. With NH-based positions for two stars alone we can figure out where the spacecraft is. This technique would be used on interstellar voyages. arxiv.org/abs/2506.21666
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These are the two stars that we used: Wolf 359 (L) and Proxima Centauri (R). These are simultaneous images from Earth and New Horizons on April 23, 2020.
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This is where we are. The interstellar navigation approach says that NH must be at the intersection of the two lines. (You can only see where the given star is in you're on its line.) The intersection falls right on the known trajectory from DSN tracking. The method works!
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🚨 BREAKING: Wow. This heart-rending ad, when tested, moves swing-state men 2.5 points away from Trump. Massive. Please share everywhere. Women are dying NOW in states with extreme bans. If Republicans win, a national abortion ban is next. Don't look away. #MAGAAbortionBan
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Women are going to protect the country from Donald Trump, whether he likes it or not.
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Tod R. Lauer retweeted
That speech Michelle Obama just gave was one of the best of this entire cycle. She is unbelievable. Here’s how she brought it home.
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Fox refuses to air this…you know what to do..#ProudBlue
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Tod R. Lauer retweeted
This one, taken just a minute or two earlier, isn't as well aligned with the lighthouse but it does show the brief "green flash" phenomenon along the top edge of the Moon there.
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The comet from my neighbors tonight. (They had the nice phone, and I fiddled it a bit). Nice in binoculars, but couldn't see it by eye.
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A bumper sticker I saw today.
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Very sad to hear of the passing of James Earl Jones. When I think of him, I take it from the top. His first movie role was as one of the bomber crew in "Dr. Strangelove."
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A treasured item on my office wall - an autographed cartoon of all the New Horizons hazard reconnaissance team members, who certified that is was safe to fly past Arrokoth.
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Today Facebook coughed up this "memory" from 11 years ago. I still cannot comprehend what's going on here:
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Sadly the actor James Darren passed away last week. He played the scientist Tony Newman in the "Time Tunnel," a 1-season SciFi TV show 1966-7, which made a huge impression on me as a 9 year-old proto-scientist. Here's Dr. Newman trying out his handiwork. youtube.com/watch?v=QAxRSe8m…
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Just how dark is deep space? 🌌 Astronomers may have finally answered this long-standing question by tapping into the capabilities and distant position of @NASA’s New Horizons spacecraft, by making the most precise, direct measurements ever of the total amount of light the universe generates. jhuapl.link/nde @NASASolarSystem
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