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ldenneau

This issue astronomers have with Starlink is not with increased light pollution per se, where the effect is negligible, but with the fact that when there are 10,000 of these in the sky at one time, it will be much more difficult to point a telescope and not have one of your exposures contaminated by a Starlink satellite passing through. Some telescopes will sit on a source for hours for the faintest objects and the odds of encountering one of these becomes worrisome.

Anything visible to the naked eye or even binoculars is honking bright to modern astronomical telescsopes, which are sensitive to sources millions of times fainter. Even if they're not directly in the field, off-axis reflections and glints can contaminate exposures. A train of these moving through the field would be a total disaster.

For those saying let's just build space-based telescopes, sure, but it's 10-100X more expensive, and even modest ground-based facilities produce 100GB/night these days, and you can't do that from space (yet).

This was answered non-facetiously after discovery: https://arxiv.org/abs/1902.04935
The ATLAS near-Earth asteroid survey (full disclosure: I am on this project) detected the Roadster last night as part of routine operations:

https://twitter.com/fallingstarIfA/status/962013418143195141

If there is one within 1 AU of the Sun at any given time, then there are ~10^16 of them within a sphere out to the nearest star. I'll leave it to you to decide whether that's teeming or not.
Co-author here. We obtained spectroscopic measurements of 'Oumuamua, and its surface closely matches D-type asteroids and comet nuclei, which are dark, reddish and organic-rich.
Re:Show HN: An easy way to convert time on Thursday June 29, 2017 @05:42PM (#14667109)
Does not handle leap seconds:

https://api.epoch.sh/2016-12-31T23:59:60Z

Edge case, but 2016-12-31T23:59:60Z is a valid UTC time.

Re:Two New Satellites for Jupiter on Wednesday June 07, 2017 @03:09AM (#14504280)
Comet Shoemaker-Levy 9 in 1994. The comet had been captured decades earlier after entering Jupiter's Roche limit and was actually in orbit around Jupiter.

Collisions in the main asteroid belt have been observed, but only after impact. The signature is a puff of dust from the impact that fades after hours or days as the dust spreads. The statistics are imprecise, but collisions between kilometer-scale asteroids might have decades or hundreds of years between them.

Impacts are rare though. There's a reason they call it space. If you were standing on an asteroid in the main belt, the nearest asteroid to you would be so far away that you could not see it.

Re:How to save datetimes for future events on Monday March 23, 2015 @05:14PM (#9253395)
I do get the point, but simply preserving the local time isn't the right answer. I'd argue that when you change your local timezone offset, then your future schedule is indeterminate and all events have to be reverified. What if the event is for an international flight -- is it still leaving or arriving at the same local time? How about that standing 9AM meeting -- is at 9 because of the corporate office in a different time zone calls in, so your local time breaks their calendar?
Re:How to save datetimes for future events on Monday March 23, 2015 @02:43PM (#9252628)
This article is way overthinking it. It's better to simply store the UTC time of the event, and nothing else. Local time zone conversions can be done when displaying/editing. Presumably at the time you are reading your calendar, your local software knows the current rules to offset from GMT.

We have Skype meetings all the time involving parties in different US timezones and/or different countries. There's no "place" or local time zone for the meeting. We schedule in UTC and our local software or calendar program knows what time zone we are in to display the correct local time.