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visviva

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yaytext.com 26d ago

YayText

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www.tomshardware.com 1mo ago

Commercial satellite supplying Intel to Ukraine cornered by Russian spacecraft

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www.reddit.com 5mo ago

Gemini responds to request to turn on lights with hallucinated jailbreak prompt

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www.donutlab.com 6mo ago

First all-solid-state battery in production vehicles

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www.hagerty.com 9mo ago

A few things to know before stealing my 914 (2022)

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www.sciencedirect.com 1y ago

17,000 new ways to multiply 3×3 matrices

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phl.upr.edu 1y ago

Wow@Home – Network of Amateur Radio Telescopes

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www.scientificamerican.com 1y ago

Dennis Gaitsgory Wins Breakthrough Prize

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nyxspace.com 1y ago

Nyx: Open-source spaceflight mechanics and mission analysis software

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www.heise.de 1y ago

Hacker hijacks and repairs Beesat-1 satellites from the ground

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research.google 1y ago

Mapping the Ionosphere with the Power of Android

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www.space.com 1y ago

US Space Force partners with India to open a microchip factory for next-gen tech

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www.esa.int 1y ago

Draco satellite mission made for destruction

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www.thespacereview.com 1y ago

To guard against cyberattacks in space, researchers ask "what if?"

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www.bloomberg.com 2y ago

The Dangerous and Lucrative Business of Space Clean-Up

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www.wired.com 2y ago

The Woman Who Showed President Biden ChatGPT – and Helped Set the Course for AI

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www.janelia.org 2y ago

Janelia reveals connectome of the fruit fly visual system

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arstechnica.com 2y ago

The Space Force is planning what could be the first military exercise in orbit

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www.washingtonpost.com 2y ago

Pentagon report finds no evidence of alien visits, hidden spacecraft

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tpalmer.medium.com 2y ago

The Domain Trap: Hiring for Domain Knowledge in Software (2021)

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bonterms.com 2y ago

Bonterms: Standard Agreements for the Enterprise

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www.scopeofwork.net 2y ago

Forming an Edge

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en.wikipedia.org 2y ago

History of the United States Space Force

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umbra.space 2y ago

Umbra Space Releases Highest Resolution Commercial Satellite Image

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techcrunch.com 2y ago

Capella’s Earth-imaging satellites are deorbiting faster than expected

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www.nasa.gov 2y ago

NASA, DARPA Partner with Industry on Mars Rocket Engine

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regex101.com 3y ago

Regex 101

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www.lewissociety.org 3y ago

The Inner Ring (1944)

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www.scopeofwork.net 3y ago

On Vulcanization

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techcrunch.com 3y ago

True Anomaly wants to train space warfighters with spy satellites

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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.

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.

Caligra Workbench 12 months ago

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.

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.

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".

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.