Cheers. Hope that would be interesting reading for those who seeks some news in the DA field
Basically, Iβm looking for an easier way to search for when a specific transit has happened in the past and/or will happen again in the future. For example, if Pluto is currently in a certain location, some kind of database where one could search and find all the past and current dates Pluto was in that same place. I hope Iβm articulating myself well as itβs kind of hard to describe exactly what Iβm looking for. It would be nice to find something more advanced where, for instance, I could look up multiple transits at once. Iβm looking for an easier way to make sense of transits and apply predictive astrology with regard to specific natal charts and the transits to them.
J'habite a Los Angeles, et je ne peux pas guetter le papeterie en BHV pour le trouver! Seulement les ephemerides tres petits sont disponible en ligne. Est-ce-que quelqu'un peut me diriger quelque part ou je peux commander quelque chose comme ca? Comme vous voyez dans le photo, c'est au moins 25 cm de hauteur, peut-etre 30 cm. J'ai pris le photo dans le Cafe St Regis a Paris. Le joli socle en bois n'est pas necessaire (mais je l'aimerais!); je peux toujours me construire quelque-chose similaire. Merci!
Hi,
I'm working on writing a program to make star charts. I've found two books which look to be helpful, Astronomical Algorithms by John Meeus and The Explanatory Supplement to the Astronomical Almanac. I'm curious which would be better for someone in my position? The Explanatory Supplement looks like it is in greater detail, so I'm leaning towards getting that one β but lots of people seem to use Astronomical Algorithms.
If it matters, I am an Astronomy major in my third year, so I've been exposed to the concepts of sidereal time, celestial coordinate systems, precession and nutation, etc. but my education has focused more on astrophysics. I have plenty of math background.
I know that Newton's constant is very poorly constrained by experiment, not nearly well enough to give a first principles calculation of the trajectories of planets and satellites, even if we knew the solar mass precisely. However even for relativistic corrections the product GM is the only number that needs to be known to determine accelerations towards the sun, and this can be determined from observing planetary motion. So I did some reading on how GM is determined and found out that people who track the planets, JPL etc., gave up on recording GM as it wasn't in fact useful for predicting things. Instead models are used that have many parameters that are fitted to past observations.
Is this more or less right? The physical significance of GM is obvious, but what about the parameters used in current models? The kicker is this, how is it that we can discern that there is an anomalous acceleration in say the Pioneer anomaly or the Fly-by effect, when, as far as I understand, the predicted accelerations are based on fittings of orbital motion to begin with.
So, I've always wondered how GPS satellites work (albeit I know the basics, I suppose) and yet I still cannot find an answer on google regarding my question. How can they cover so many signals, so many GPS-related needs with so few satellites? Do they not have a limit?
I mean, Elon is sending way more up just for satellite internet, if I am correct. Can someone please explain this to me?
Disclaimer: First ever post here, one of the first posts/threads I've ever made. Sorry if something isn't correct. Also wasn't sure about the flair, although I hope Engineering covers it. Didn't think Astronomy would fit, but idk. It's "multiple fields" of science.
And ~ thank you!
I don't want to step on anybody's toes here, but the amount of non-dad jokes here in this subreddit really annoys me. First of all, dad jokes CAN be NSFW, it clearly says so in the sub rules. Secondly, it doesn't automatically make it a dad joke if it's from a conversation between you and your child. Most importantly, the jokes that your CHILDREN tell YOU are not dad jokes. The point of a dad joke is that it's so cheesy only a dad who's trying to be funny would make such a joke. That's it. They are stupid plays on words, lame puns and so on. There has to be a clever pun or wordplay for it to be considered a dad joke.
Again, to all the fellow dads, I apologise if I'm sounding too harsh. But I just needed to get it off my chest.
