Every day, observations and orbit solutions for Near-Earth Asteroids (NEAs) are received from the Minor Planet Center (MPC) in Cambridge, Massachusetts. Once classified as an NEA, the asteroid is thereafter given automatic orbit updates within our Sentry system. A new orbit solution for an NEA is computed whenever new optical or radar observations for that object become available. Some high-priority objects are observed daily, while other objects go unobserved for days or weeks, even though they may still be bright enough to be seen. Optical observations cease when an object recedes from the Earth (becoming too faint to be seen even with moderate-size telescopes), or when the object moves into the daytime sky. Similarly, radar observations are possible only when the object is near enough to the Earth for the echo of a radar bounce to be detected. Once all the observations for an object have been collected, an orbit determination process is used to find the orbit that best fits all the observations.
It is important to understand that an object’s orbit is never known perfectly. Although the nominal orbit solution fits the observations best, slightly different orbits may still fit the observations to within their expected accuracies. There is in fact a whole set of orbits around the nominal that will fit the observations acceptably well: these all lie within what we call the uncertainty region about the nominal orbit. The ‘true’ orbit is expected to lie somewhere within this region. As new observations of the object are made, the uncertainty region becomes more tightly constrained and the range of possible values for the orbital elements narrows. As a result, objects that have been observed for decades will have highly constrained, well-known orbits, while newly discovered objects tracked for only a few days or weeks, will have relatively poorly constrained, uncertain orbits.
Once the nominal orbit and its associated uncertainty region have been determined, the object’s motion is numerically propagated forward in time for at least 100 years in order to determine its close approaches to the Earth. These nominal orbit close approach predictions are tabulated in our Earth Close Approach Tables along with other uncertainty-related information such as the minimum possible close approach distance, and the impact probability. The uncertainty-related parameters in the close approach tables are computed by propagating the uncertainty region from the epoch to the respective close approach times via so-called linearized techniques. Since these techniques lose accuracy when the uncertainties become large, we include only reasonably certain predictions in our Close Approach Tables. As a result, close approaches may be tabulated decades into the future for objects with well-known orbits, but only a few months or years into the future for objects with poorly known orbits. On the other hand, Sentry assesses the long-term possibilities of an Earth impact for all objects whose orbits can bring them close to the Earth, even those with poorly known orbits. To perform this risk analysis Sentry uses more sophisticated nonlinear methods.
I don't know if there's an API or feeds or what, I haven't looked that closely into it yet.
A century after the cataclysmic Earth-Space War between the colonies and the Earth Protectorate, most of the human population now dwells in space. People depend on technology for every moment of their survival, and machines depend on technopaths - Autistics trained from a young age and modified to interface with computers directly. These are their stories.
Our flagship story Ætherglow is updated frequently and directed by polls. To participate, just read the story and vote in the polls with each post to decide the fate of an Autistic femboy technopath in training at Translunar Academy.
All fiction and art on this site are published here for free. Follow with an RSS reader to be notified of new posts, or follow us on the fediverse.
Space Nerds In Space is an open source (GPLv2) cooperative multiplayer starship simulator for linux (may also work on Mac). So go out and get together with a crew of your linux-nerd friends and their computers in a room with a projector or TV, and go forth and explore the galaxy.
One computer runs the central server simulation of the game's universe. Each player's computer acts as a station on a simulated spaceship. There are stations for Navigation, Weapons, Engineering, Communications, Damage Control, and the "Main View", an out-the-window 3d rendering. Multiple starships each with their own team may connect to the server for bridge-vs-bridge combat, or for cooperative play. Additionally, a game master may inject and control various NPC ships into the game to entertain the players, and scenarios may be constructed with a Lua based scripting API.
Source code: https://github.com/smcameron/space-nerds-in-space
When and where can you see the northern and southern lights also known as the aurora? This page provides a prediction of the aurora’s visibility tonight and tomorrow night in the charts below. The animations further down show what the aurora’s been up to over the last 24 hours and estimates what the next 30 minutes will be like. The aurora’s colorful green, red, and purple light shifts gently and often changes shape like softly blowing curtains.
The SuperNova Early Warning System (SNEWS) is a global network of neutrino experiments sensitive to supernova neutrinos. The goal of SNEWS is to provide the astronomical community with a prompt alert of an imminent Galactic core-collapse event. This will allow for complete multi-messenger observations of the supernova across the electromagnetic spectrum, in gravitational waves, and in neutrinos.
The observation of a neutrino burst can thus provide a warning for astronomers that the opportunity to get a rare glimpse at the collapse of a star, resulting in a supernova, may soon be presenting itself. In addition, there is a real chance that a Galactic supernova may be observable with the naked eye, making this alert interesting to hobby astronomers and the general public alike. Most large-scale neutrino detectors around the globe thus joined forces in the SNEWS network to provide a high-sensitivity alert to interested parties. In addition, gravitational wave detectors like LIGO and Virgo have sensitivity to asymmetrically-collapsing supernovae and can both benefit from and contribute to such an alert.
The early supernova alert project has a central computer which accepts neutrino burst candidate messages from neutrino detectors around the world and sends an alert to astronomers if it finds a coincidence within a few seconds.
A free service for querying which satellites will be passing over a known location on the globe.
In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For many years this site coordinated its efforts with the Tau Zero Foundation. It now serves as an independent forum for deep space news and ideas.
RSS: https://follow.it/centauri-dreams-imagining-and-planning-interstellar-exploration/rss
Mothership is a sci-fi horror roleplaying game where you and your crew try to survive in the most inhospitable environment in the universe: outer space! You'll excavate dangerous derelict spacecraft, explore strange unknown worlds, exterminate hostile alien life, and examine the horrors that encroach upon your every move. Designed from the ground up to be intuitive to run and easy to play, no system-mastery required. d100. Designed for very fast character generation.
The Player's Survival Guide is the core book.
Software that emulates the guidance computer of the Apollo space capsules.
The website for a classic space trading/warfare game called Elite run by one of the original authors. Includes a lot of information and even the novella which was published with the original version.
A far future RPG in which the players play field agents keeping the peace between a dozen civilizations by any means necessary throughout the universe. Also has strong themes of political intrigue, wonder, and responsibility. Published under the Creative Commons v3 license, though you can purchase PDFs of it from DriveThruRpg.com or buy dead trees from lulu.com if you want to support the project.
A point-in-time simulation of the position of the planets in the solar system, based upon date and time. Also calculates the ephemera for the planets at that point in time.