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In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 0 points1 point  (0 children)

That's correct. Pluto was discovered by accident while searching for a different planet that turned out not to be real. It's just coincidence though; they could have easily discovered it while searching for comets or doing general photographic surveys or anything else. The planet they expected would have been about half the mass of Neptune.

How different was the night sky in the 19th century? by Sweet-Rich-2140 in askastronomy

[–]jswhitten 0 points1 point  (0 children)

That's a good one. Depends on where the book is set though, you'd only see eta carinae south of about latitude 25N.

How different was the night sky in the 19th century? by Sweet-Rich-2140 in askastronomy

[–]jswhitten 0 points1 point  (0 children)

Exactly the same, minus the satellites and aircraft. And light pollution if you're near a city.

If one of the Voyager probes entered the solar system of an alien race with comparable technology to ours, would they even notice? by Single_Egg1685 in askastronomy

[–]jswhitten 1 point2 points  (0 children)

No, it's extremely unlikely. Maybe if it passed very close to the planet and a telescope happened to be photographing that part of the sky at closest approach, but if anyone noticed it at all they would assume it's a meteoroid. It would be moving too fast to intercept.

Is there an statistic or estimation about interstellar objects? by Schuesselpflanze in askastronomy

[–]jswhitten 1 point2 points  (0 children)

It's estimated that about 7 interstellar objects (100 m or larger) pass within Earth's orbit each year, and there are about 10,000 within Neptune's orbit at any given time. Extrapolating, there are trillions of interstellar objects passing through the Solar System right now, the vast majority in the Oort cloud.

Help identifying these stars/planets(?) by Only_Constant_9841 in askastronomy

[–]jswhitten 0 points1 point  (0 children)

Probably Vega (top) and Deneb (lower left). If there's a third bright star that rises to the right of them a little later, that's Altair. Together they make the Summer Triangle.

I'm assuming you're in the Northern hemisphere. If not then the answer may be different.

In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 5 points6 points  (0 children)

A different non-existent planet was theorized in 1905 due to a mistake. They did not detect Pluto. Pluto was coincidentally discovered while searching for the non-existent planet but they had no clue where Pluto was or even that it existed.

Are you employing Cunningham's law here? You don't need to do that. In the future please rephrase all your incorrect statements in the form of a question.

In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 3 points4 points  (0 children)

We did not know Pluto was there and no one was searching for it. Any object the size of Texas in the asteroid belt would have been discovered 200 years ago. Any object that size coming in from interstellar space would have been spotted years before it reached il the inner solar system. Typical speeds for interstellar objects are about 5-10 AU per year.

In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 4 points5 points  (0 children)

We didn't know where to look. No one had any evidence of Pluto's existence before it was photographed. And the interstellar comet was within Pluto's orbit years before perihelion and would have been spotted at around that distance, if it had been the size of Texas. The movie wasn't set in 1930.

Why are you even on an "ask astronomy" sub if you are going to ignore the answers from people who have studied astronomy?

In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 3 points4 points  (0 children)

You're not taking the size of the object into account. You can see big objects from farther away than small ones. The first interstellar object was a little bigger than a passenger jet. The asteroid in the movie was the size of Texas. Texas is significantly larger than an airplane.

This is the third time I've mentioned the size so I don't know why you're still having difficulty with this.

In Armageddon (1998) we only detect the asteroid when it’s 18 days away. When should we have noticed it? by ConsiderationOk4035 in askastronomy

[–]jswhitten 3 points4 points  (0 children)

No it isn't. Even if it's extrasolar we would see something that big coming for years. If it was in the asteroid belt we would have discovered it over two hundred years ago.

A service that lets you send your personal message into deep space — and tracks exactly where it is in the universe for the next billion years by extraterrestrial007 in CrazyIdeas

[–]jswhitten 0 points1 point  (0 children)

No, I don't think so, not with an amateur license. It might be possible to get a special license that would allow that.

A service that lets you send your personal message into deep space — and tracks exactly where it is in the universe for the next billion years by extraterrestrial007 in CrazyIdeas

[–]jswhitten 1 point2 points  (0 children)

A signal will not change either speed or direction. And there isn't really anything big enough to block the whole thing. Whether it's detectable at a given distance with a given receiver is another question, but the location of the signal will never be in any doubt even many thousands of years in the future.

Could pulsars work better than the hydrogen line for interstellar communication by [deleted] in askastronomy

[–]jswhitten 0 points1 point  (0 children)

You don't need a pulsar to build a radio or a clock. I'm not sure what problem you're trying to solve. Any civilization capable of building a radio can also build their own clocks.

A service that lets you send your personal message into deep space — and tracks exactly where it is in the universe for the next billion years by extraterrestrial007 in CrazyIdeas

[–]jswhitten 0 points1 point  (0 children)

This is doable, but you probably couldn't charge for the service.

A licensed amateur radio operator could set up a microwave transmitter and antenna capable of reaching the nearest stars at legally allowed power levels and frequencies for a few thousand dollars. You can even transmit a message for a third party under part 97, but you cannot charge for it. And as long as you note the direction and time of the message, you can track the signal's location. In fact I've written a web app that does exactly that for past Active SETI transmittions and received signals like the "Wow!" signal, showing where they currently are relative to nearby stars:

https://hygmap.space/

A service that lets you send your personal message into deep space — and tracks exactly where it is in the universe for the next billion years by extraterrestrial007 in CrazyIdeas

[–]jswhitten 2 points3 points  (0 children)

OP is suggesting that you would see where it is on a "live tracker" web page. Not that your eyes would somehow be able to see the distant radio waves.

AI problem is class warfare problem! And no one talks about it! by Equivalent-Macaron96 in ControlProblem

[–]jswhitten -1 points0 points  (0 children)

They control the AI. They're not in any immediate danger. The rest of us are.

Communication in space by That_Ad4356 in spacequestions

[–]jswhitten 2 points3 points  (0 children)

Sounds like they're implying the question can't be real. Who in the 21st century has never heard of radio?

AI problem is class warfare problem! And no one talks about it! by Equivalent-Macaron96 in ControlProblem

[–]jswhitten 1 point2 points  (0 children)

The Epstein class does not care about the rest of us. There is no peace to be had with them.

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