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First Extrasolar Object Observed Racing Through Our Solar System (space.com)
Enigma2175 writes: For the first time, scientists have observed an object they believe came from outside our solar system. The object is in a hyperbolic orbit that will send it back into interstellar space. From Space.com: "The object, known as A/2017 U1, was detected last week by researchers using the Pan-STARRS 1 telescope in Hawaii. 'It's long been theorized that such objects exist -- asteroids or comets moving around between the stars and occasionally passing through our solar system -- but this is the first such detection,' Chodas added. 'So far, everything indicates this is likely an interstellar object, but more data would help to confirm it.' It's unclear what exactly this thing is. When A/2017 U1 was first spotted, it was thought to be a comet (and was therefore given the moniker C/2017 U1). But further observations have revealed no evidence of a coma -- the fuzzy cloud of gas and dust surrounding a comet's core -- so the object's name was amended to its current asteroidal designation."
It's already heading out of the solar system, so no need to worry about any malicious intent. TFA says that it passed perihelion around Sep. 9. It was closest to the Earth on Oct 14, at about 15 million miles (24 million km, sorry don't have it in LOC). It's heading toward the constellation Pegasus at over 97000 mph. Maybe we'll send them a warning in a few years?
It's a bit unsettling that we didn't notice this until it had passed the earth at a relatively close distance, and passed through the plane of the ecliptic twice. I know the chances of an impact are very low, but the late detection indicates that we may be missing an unknown number of events like this, and may not be correct about estimates of the chances of being hit by one.
Interesting that it came in perpendicular to the ecliptic plane inside Mercury's orbit slingshots around the sun and then makes a b-line for Earth making a close approach at 15 million miles.
Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.
Incorrect. For 'queue' or 'cue', either can be correct and only the speaker can say for sure which they wanted as grammatically both make sense. If he's got a list of things to do, saying "queue" is correct if he means 'add the rendezvous to the list of things needed to be done'. Now if he meant it's time to start the rendezvous, then yes, cue would be correct.
When dealing with ambiguity, it's usually best to give them the benefit of the doubt than assuming they meant what you think they meant.
Escape speed from 1 AU (Earth's orbital radius) is about 42 km/s. The speed of this object, stated as 156,400 km/h, is just over 43/km/h. Assuming the object is a bit more than 1 AU from the Sun right now, it will escape the solar system but not by a wide margin.
"Rendezvous with Rama" was a great book.