The Moon just finished occulting Jupiter. Here's a simulated view. 🔭#astro
Tony Dunn
@tony873004.bsky.social
Orbit simulations of planets, comets, asteroids and other interesting stuff. Amateur astronomer. BA: Physics & Astronomy, SFSU.
Tomorrow night, ESA's JUICE spacecraft will make a close pass by Neptune as seen from the U.S.—and along a narrow path across North America, it will transit directly across Neptune. JUICE should be around mag 12–13. Here's what the encounter will look like from different cities. #astro 🔭
A view of Earth from JUICE. On Sept 27/28 ESA's JUICE mission will pass Earth for a gravity assist on its way to Jupiter. It may be bright enough for astrophotographers worldwide. Before close approach it will pass through Earth's shadow. JUICE will study Jupiter's icy moons. #astro 🔭
Yesterday, newly-discovered asteroid 2026 SZ2 pass closer than our geostationary satellites. It is 1-5 meters across. 🔭 #astro
10,000 years of asteroid orbits precessing around the Sun. 🔭 White: Main Belt asteroids Magenta: Near-Earth asteroids Watch how the orbital planes slowly rotate and pulsate. #astro
To be a star, all you need to do is sustain fusion in your core. But the range of brightnesses is staggering. 🔭 #astro
Asteroid CERNQ52 entered Earth's atmosphere today over the ocean south of Indonesia. It was discovered by the Mount Lemmon Survey in Arizona only hours before its demise. At 80 cm wide, it would have caused no damage. I had to exaggerate the size here, so you could see it. 🔭 #astro
The #SanFrancisco #49ers arrived in Melbourne today, a week prior to their game against the #LosAngeles #Rams. The Rams wont leave until the day before the game. Whose travel plan makes more sense?
Is Sar2901 a mini-moon or space junk? Even the Minor Planet Center isn't sure. The astronomy community is divided. More observations in November should help settle the debate.🔭 #astro
Launched today! 🚀 NASA's Nancy Grace Roman Space Telescope is now on its way to Sun-Earth L2, ~1 million miles away. It will survey billions of galaxies, probe dark energy & dark matter, and discover exoplanets. #RomanSpaceTelescope #NASA #Astro🔭 #Space
Why don’t eclipses happen every month? The Moon’s 5° orbital tilt causes frequent misses, aligning only during brief "eclipse seasons." Tonight is the encore to the recent total solar eclipse. Here is a front-row view of Earth from the lunar surface! #astro 🔭
Why do flight paths curve on flat maps? Watch the great circle route between San Francisco and London turn into a straight line as the projection shifts. Flat maps lie, geometry doesn't! ✈️🌍 #GreatCircleRoute #DataViz 🔭 #astro
It's getting close. The Falcon-9 stage is less than an hour away from impacting the Moon.🔭
On Tuesday evening, August 4, a Falcon 9 rocket stage will slam into the Moon. Will the impact and plume be bright enough to see from the Americas? 🔭#astro
Asteroid Torifune was just imaged by Japan's Hayabusa 2. This asteroid is a rubble pile. If you could gently place it in the middle of a parking lot, it might look something like this. 🔭 #astro
Why is tonight's Full Moon so low? For the Northern Hemisphere, around the June Solstice, the full Moon takes its lowest path of the year. We're also near a minor lunar standstill, making the Moon's nightly path even lower than usual. 🔭 #astro
For a couple weeks around the 𝐉𝐮𝐧𝐞 𝐒𝐨𝐥𝐬𝐭𝐢𝐜𝐞, there is a brief moment each day when 𝟏𝟎𝟎% of mainland North America is on Earth's day side while 𝟏𝟎𝟎% of mainland South America is on Earth's night side, defined by 𝐭𝐡𝐞 𝐭𝐞𝐫𝐦𝐢𝐧𝐚𝐭𝐨𝐫. 🔭 #astro
A proposed mission to Kuiper Belt object 2002 XV₉₃ • Launch: 2034 • Jupiter gravity assist • Uranus plane-change maneuver • Flyby in 2043 Trajectory found by @adamsspaceresearch.bsky.social. www.youtube.com/watch?v=FHV4... 2002 XV₉₃ is in the news because it may possess a thin atmosphere.
Tomorrow, asteroid 2026 JH2 will pass less than 1/4 the distance of the Moon as it flies over South Africa. #astro 🔭
This asteroid, previously known as ST26E86 is now known as 2026 JN4 🔭 #astro
Tony Dunn@tony873004.bsky.social · 5mo agoEarlier today, an asteroid about the size of a person impacted Earth over Papua New Guinea. This is only the 12th object to be discovered before impact. #astro 🔭
Earlier today, an asteroid about the size of a person impacted Earth over Papua New Guinea. This is only the 12th object to be discovered before impact. #astro 🔭
Inspired by the 12,000 Artemis II images just released, a simulation of Earthset as seen by the astronauts (3:16 real time). A bit slower than a sunset on Earth. 🔭 #astro Timelapse (15 seconds): orbitsimulator.com/BA/artemis_I... Real speed (3:16): orbitsimulator.com/BA/artemis_I...
A rocket booster will slam into the Moon on August 5. 2025-010D is the upper stage of a Falcon 9 rocket that brought the Blue Ghost Mission 1 to the Moon.
Newly-discovered asteroid 2026 HZ4 approached closer than our geostationary satellites 2 days ago. It is 2-7 meters wide. 🔭
Artemis II splashdown off San Diego, less than 45 minutes from now. Inertial frame.
Artemis II doesn’t reverse direction like its ground track implies. Far out, its motion is mostly radial (toward Earth), so its small eastward speed is slower than Earth’s rotation, so it appears to drift west. Closer in, tangential speed grows and overtakes Earth’s rotation, so it moves east.
In a few hours, at ~9 PM PDT, Artemis II will be halfway between Earth and the Moon (by distance). The Moon will look unusually large to the crew. But they’re not halfway there in time. Earth’s gravity has been slowing them the entire way, and will continue to do so.
