visviva

Hate when my Nasic and past performance are left unpaired

The weapon you linked to is an anti ballistic missile. The difficulty is not purely in how fast the target is going, but how much it maneuvers, the duration at which it can sustain those speeds, and the altitudes at which it operates. The article addresses this early on.

Suggest changing the title to include both parts, if they fit: "Tim Cook to become Apple Executive Chairman, John Ternus to become Apple CEO"

Totally agree. Cool little project, but I cannot think of one use case where this is needed.

> But "fine" starts to feel slow when you need dense time resolution. Generating a month of ephemeris data at one-second intervals is 2.6 million propagations per satellite.

Ok, except SGP4 loses its accuracy over WAY shorter time frames than a month (think hours/days)

> Pass prediction over a ground station network might need sub-second precision across weeks.

a) sub-second ephemeris for antenna pointing is crazy overkill, and b) same comment about accuracy as above.

Impossible claim with no evidence offered - curious why this is on the front page.

It will require a number of innovations just to solve the formation flying aspect of the system, not to mention the other challenges (listed and not)... good luck with that.

There are a couple interesting-sounding claims made here but there is basically no detail to be found, which strikes me as odd at best and suspicious at worst.

I've been using Instapaper for many years to collect things to read later, and I use Pinboard to archive things that I've read and want to save.

I was kind of hoping for a deep-dive on notebook types and features, not gonna lie.

*The problem with modern software engineering

The paper in question is here: https://link.springer.com/article/10.1007/s40295-024-00458-3

It adds to a pretty large body of literature around this subject, the gist of which is "risk is going up, but we don't really have a good way of estimating what that means in terms of actual collision rates".

Astrodynamics

The most likely options are that it was struck by debris or that there was an explosion onboard. Those two are not mutually exclusive, either.

This has been an indispensable resource in my career, to the point that I will frequently search for "<topic of interest> gunter", knowing that he'll have the best collection of information available openly.

The combination of mm-level precision and a highly elliptical orbit with a very high apogee (60+ kkm) is really impressive.

Are you familiar with the Tracker Component Library[1]? Similar concept, although I like the fact that you show examples in the README.

[1] https://github.com/USNavalResearchLaboratory/TrackerComponen...

In what industry are Kalman filters ridiculed?

I've been wishing for this for years!

"The allegations were brought by Matthew Decker, who served as the chief information officer for Penn State’s Applied Research Laboratory"

As far as I can tell, only 1 out of the 45 laws (#45) potentially refers to human spaceflight.

What makes you think this is limited to human-rated spacecraft?

This is a common approach - besides being robust to lighting conditions, it's less sensitive to glinting.

To me, "ranging" means measuring the range to the target directly, not estimating it from other measurement types (bearings, for example). Can someone explain if that's what the authors are doing here? Is it analogous to stadiametric ranging? I haven't read through this in depth, but I can't figure out what their method is.

Where would you recommend one visit if they wanted to experience this "real world"? Better yet, what's the realest place one could visit, based on your metrics of restaurants and personal accessories?

edit: thank you all for your travel suggestions, but this was a tongue-in-cheek way of trying to point out the absurdity of the OP's comment about DC not being the "real world".

Seems like your comment could really benefit from some links to supporting information, since the very existence of this article is proof that not everyone knows what the company is doing.

Relevant part of a weirdly long (IMO) article: "...Kirkpatrick didn’t specify the types of sensors or where they will be located."

> Plain Language Summary: On 03 February 2022, SpaceX launched 49 Starlink satellites into staging orbits at 210 km above sea level prior to raising them to their operational altitudes of 550 km. The pre-launch space weather briefing included no information about an ongoing geomagnetic storm. Excessive atmospheric drag due to the geomagnetic storm resulted in 38 of the satellites re-entering the atmosphere on or about 07 February 2022. We use both models and direct measurements of the atmospheric density during the event to show that density values were enhanced by 20%–30% at the 210 km staging altitude relative to values prior to the geomagnetic storm onset, while they were enhanced 90%–160% at higher altitudes. We recommend improving our ability to model the upper atmospheric response to geomagnetic storms to provide accurate forecasts and actionable “nowcasts” of conditions in low Earth orbit to launch controllers, space traffic managers, and satellite operators.

> a basic mistake huh?

Yes, a basic mistake. I'm not sure what you're getting at with your comment, but this is literally the kind of thing that should be caught very early on, probably just by updating a few parameters (or even just one) in the attitude control sim and observing the outputs.

If this claim is true (a big "if", admittedly), this is a breakdown in the kind of fundamental systems engineering that they teach to undergrads building cubesats.

Pretty mind-blowing if true. That is an unbelievably basic mistake to make.

Perhaps you missed the paragraph that answers your question - it's nestled between the two quotes you cite.