RossSJun 20

Summer solstice overnight tonight!

And my semi-annual reminder that the solstices are neither the earliest/latest sunrise or latest/earliest sunset...just the longest/shortest period of daylight between the two...it's just the point in time summer/winter that the Earth's axial tilt is most directed towards or away from the Sun. The extremes of rise or set actually happen a few days either side of the solstices.

ps: The Earth is actually closer to the Sun in the winter, not the summer...another little factoid...at least for the northern hemisphere...

#Earth #Sun #OrbitalDynamics

AlcorNewsJul 13, 2025
Des astronomes identifient des comètes sombres, objets déguisés en astéroïdes mais propulsés comme des comètes, un vrai casse-tête cosmique
https://www.pourlascience.fr/sd/astronomie/les-cometes-sombres-des-objets-celestes-qui-defient-les-lois-de-la-dynamique-du-systeme-solaire-27912.php
#Space #Science #Innovation
#Astrophysics #OrbitalDynamics
#DarkComets #NEOs #OutgassingMystery
#CosmicFrontierEmerging
Pustam | पुस्तम | পুস্তম🇳🇵Mar 27, 2025

Evolution of the price per kg of payload (LEO) for several space missions:

🇺🇸 Space Shuttle - $19.8k/kg
🇪🇺 Ariane 5 - $10.3k/kg
🇷🇺 Soyuz FG - $7.2k/kg
🇯🇵 H-IIB - $7.1k/kg
🇨🇳 LongMarch 3B - $5.8k/kg
🇮🇳 Polar Satellite - $3.9k/kg
SpaceX Falcon - $2.7k/kg
SpaceX Falcon 9 (reuse) - $1.9k/kg

#Space #SpaceShuttle #Payload #SpaceMission #SpaceMIssions #Evolution #LEO #LowEarthOrbit #Mission #Missions #Shuttle #Ariane #Ariane5 #Soyuz #SoyuzFG #HIIB #LongMarch #LongMarch3B #PolarSatellite #SpaceX #Falcon #Falcon9 #Reuse #SpaceScience #Planet #SpaceTech #Astrodynamics #Astrophile #OrbitalDynamics #Technology #STEM

Ansgar Schmidt Jan 10, 2025
Tianwen-1 second apoapsis raise https://destevez.net/2025/01/tianwen-1-second-apoapsis-raise/ #orbitaldynamics #satellites #tianwen #events #space
Tianwen-1 second apoapsis raise – Daniel Estévez

Ansgar Schmidt Oct 12, 2024
Lagrange Points and Why You Want to Get Stuck At Them https://hackaday.com/2024/10/09/lagrange-points-and-why-you-want-to-get-stuck-at-them/ #jameswebbspacetelescope #orbitaldynamics #originalart #asteroids #featured #lagrange #science #space
Lagrange Points And Why You Want To Get Stuck At Them

Orbital mechanics is a fun subject, as it involves a lot of seemingly empty space that’s nevertheless full of very real forces, all of which must be taken into account lest one’s spacec…

Hackaday
Ansgar Schmidt Jun 4, 2023
Mars Express 20th anniversary livestream https://destevez.net/2023/06/mars-express-20th-anniversary-livestream/ #orbitaldynamics #satellites #space
Mars Express 20th anniversary livestream – Daniel Estévez

Show threadNafnlaus 🇮🇸 🇺🇦Nov 20, 2022

@ross Play #KerbalSpaceProgram for a while, you'll get a much better understanding of the (very counterintuitive) nature of #OrbitalDynamics :)

Oh, and how did they calculate things in the #1960s? While final trajectories were analyzed with (compute-intensive) #NBodySimulations, rough trajectories were created with "#PatchedConics", which basically sort of converts a trajectory into a #geometry problem.

Ian J. O'NeillNov 14, 2022
NASA's #CAPSTONE mission has arrived at the #Moon, becoming the first #CubeSat to orbit the moon and the first spacecraft ever to occupy a near-rectilinear halo orbit (NRHO) - the same orbit that will be used by Gateway, the space station that will support the #Artemis Program: https://blogs.nasa.gov/artemis/2022/11/13/capstone-arrives-to-orbit-at-the-moon/ #orbitaldynamics #space #nasa #satellites
CAPSTONE Arrives to Orbit at the Moon – Artemis

Ansgar Schmidt Nov 8, 2022
Dancing with the (Six) Stars, or, a 200 year story of the Castor system https://astrobites.org/2022/11/07/castor-interferometry-orbits/ #opticalinterferometry #dailypapersummaries #orbitaldynamics #interferometry #dynamicalmass #sextuplestars #binarystars #triplestars #castor #orbits #chara
Show threadLes capsules du prof LutzDec 31, 2021

@manu

<avec une voix de père noël agacé qui tient un ticul sur ses genoux> :

«Bon, j'comprends pu là...Quesses-tu veux pour Noël? Orbiter autour de L2 ou de L4-L5? Euh, non (osti qu'chu méta😏 ) Tu veux la souveraineté ou tu veux un bon gouvernement? Tu veux pas les deux?» #politique #orbitaldynamics