Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

New Horizons: Nasa spacecraft speeds past Pluto

bbc.co.uk

Post reply on HN
Print view View original

181–190 of 309 posts

Re: New Horizons: Nasa spacecraft speeds past Pluto

#181

Post by jsmthrowaway »

scrollaway wrote: post #115
kale wrote: post #102

Earlier quoted context omitted.

What continent are you referring to that has two countries? North America has 23 countries, with the U.S.A., Canada, and Mexico being the largest countries.

Sorry, I meant two other countries and you're right; I have edited to clarify. My point was centered on borders and neighbouring countries. Do you ever see US immigration politics talking about anything else than Mexico? Canada + Mexico + the US occupy something like 95% of the landmass alone. Whenever you hear people talk about immigration in europe, we're talking about immigration from generally 5+ other countries,…

When we discuss immigration we are talking about immigration from generally the entire planet, including Europe. I can think of noteworthy discussion around Cuba, Asia, refugees from numerous conflicts, all of South America... we immigrate far more people and nationalities than you would ever dream because of historical status and in spite of our broken system.

We have an illegal immigration problem from Mexico due to conditions there and our border situation. However, countless people from South America flow though the same system by buying their way to Mexico first. That's the immigration politics you observe, because how to handle it is partisan.

This whole thread, which was extraordinarily stupid from the get go, is amounting to Europeans explaining the U.S. to the U.S. You guys are getting it wrong, too, your comments included. Who gives a shit about immigration policy? We are in a bloody thread about mankind's achievement in space. Christ, hang it up for one day.

Re: New Horizons: Nasa spacecraft speeds past Pluto

#182

Post by bargl »

Splendor wrote: post #153
Mahn wrote: post #106

Apparently it snows on Pluto: Pluto has an atmosphere. It snows on Pluto and the snow sublimates back into the atmosphere. https://twitter.com/OSIRISREx/status/620932748824285184

With a 248-year orbit around the sun those must be some long winters.

I know I'm sorry I'm sorry but I can't help myself.

"Winter is coming."

Re: New Horizons: Nasa spacecraft speeds past Pluto

#183

Post by chc »

ceejayoz wrote: post #172
grinich wrote: post #166

Earlier quoted context omitted.

A bullet travels about 1,700 MPH. New Horizons is going about 36,300 MPH. The probe weighs 480 kilograms, so it's kinetic energy is approximately 63.2 Gigajoules. For reference, this is like 15 tonnes of TNT released on impact. Hard to make something that survives those kind of conditions.

Plus, probes that far out have worse-than-dialup transmission rates. It takes 42 minutes to return a single photo from the LORRI camera. Bursting large amounts of data out in a short period of time before impact isn't feasible. http://www.planetary.org/blogs/emily-lakdawalla/2015/0130080...

I think the suggestion was to send the data after impact. I guess the idea is to basically fire a shock-absorbing crate full of scientific instruments, let the impact destroy the crate, and hope the instruments survive and get to work.

Re: New Horizons: Nasa spacecraft speeds past Pluto

#184

Post by jsmthrowaway »

pluma wrote: post #123
snowwrestler wrote: post #91

Earlier quoted context omitted.

People chanting "USA" are literally not saying "in your face, my country is better that yours." I think if that's what you're hearing, you're bringing some personal interpretation to your hearing.

What you seem to miss is that Americans chanting "USA" is so frequent and so common even in situations that wouldn't be considered to warrant any nationalism by anyone else that it's a point of ridicule by anyone else. Case in point, this: https://www.youtube.com/watch?v=bhITpTtG888

Please, keep explaining America to us. Most of the socially liberal Americans consider it just as ridiculous and it is regularly parodied in our media all the time. I especially love that you dug up an obviously ironic chant by college students at the presence of a bald eagle and cited it as if it meant something. The bald eagle is our national symbol and is so over-the-top American that I could see the joke immediately, but I guess I understand how it would be lost on a European. That you take that video seriously is hilarious.

There's something I could counter relating to certain European tendencies to explain the world to the world since certain parts of Europe still consider most of the planet as belonging to them, but I won't, because this isn't the thread or the place. Did everybody in this thread wake up today and say "gosh, I'm going to argue about America in a thread about Pluto, that's my achievement for the day"?

Re: New Horizons: Nasa spacecraft speeds past Pluto

#185

Post by vlasev »

artur_makly wrote: post #173

So this got me thinking... is there a way to forecast our space-travel capacity into the far future? Could we conceivably create a formula that takes into account all of humanity's previous milestones of technological breakthrough's and the distances they have achieved for us.. and project where we could be 100, 500, 1000 yrs from now? Perhaps there is a vague velocity pattern we can derive from a plethora of histori…

The closest thing I know about, that's close to what you are talking about, is the wait calculation. Basically, if you assume that the velocity we can attain grows exponentially, and if you do a calculation, you'll find a "best time" when to launch. Assuming that the velocity grows with an exponential growth of 1.4%, equal to the current world economic growth, says that the earliest we would expect to get to the closest star is 1110 years from 2007, or 3117.

https://en.wikipedia.org/wiki/Wait_Calculation

Re: New Horizons: Nasa spacecraft speeds past Pluto

#186

Post by jsprogrammer »

jccooper wrote: post #168
chasing wrote: post #160

Earlier quoted context omitted.

Any actual engineer will probably find this comment painfully naive, but here we go: If it's infeasible to slow down to get into orbit or land on Pluto, what about the feasibility of designing a probe to impact Pluto at XX km/sec and survive well enough to send back data. Like, fire a (metaphorical) bullet full of scientific instruments directly into the surface of the planet. Is it simply that we have no way to buil…

Bullet goes about 1.2 km/s at best. New Horizons is going ~14 km/s relative to Pluto. That's a heck of an impact to survive. You could do it on Earth by braking in the atmosphere, but there's not a lot of that on Pluto.

If you were trying to land, you would use a different trajectory that doesn't result in you traveling 14 km/s to Pluto?

Re: New Horizons: Nasa spacecraft speeds past Pluto

#187

Post by mturmon »

pluma wrote: post #123
snowwrestler wrote: post #91

Earlier quoted context omitted.

People chanting "USA" are literally not saying "in your face, my country is better that yours." I think if that's what you're hearing, you're bringing some personal interpretation to your hearing.

What you seem to miss is that Americans chanting "USA" is so frequent and so common even in situations that wouldn't be considered to warrant any nationalism by anyone else that it's a point of ridicule by anyone else. Case in point, this: https://www.youtube.com/watch?v=bhITpTtG888

I admit, that's laughable (and I did get an honest laugh, and upvoted you for the pleasure), but that was taken at Oral Roberts University, which is a fundamentalist college founded by one of the most notorious ex-Pentecostal televangelists my fair nation has ever produced. And that's saying something.

In other words, about as representative of Americans as a Le Pen rally is about French.

[Contra another comment nearby: due to the venue, I believe it was a genuine chant, not ironic, although probably a bit giddy. If it had been a more mainstream university, I agree, that would have definitely been a goofy ironic chant.]

Re: New Horizons: Nasa spacecraft speeds past Pluto

#188

Post by [deleted] »

chasing wrote: post #160
kartikkumar wrote: post #89

Quote from a friend of mine on the team: "After 9.5 years and 6 billion km, we made it to Pluto 72 seconds ahead of schedule." Amazing! The views of Pluto and Charon already reveal how incredibly fascinating this system is. The dichotomy of their surface colours will most definitely lead to further insight into formation processes in the Kuiper Belt. Just such a shame that we can't land this time around. With the vol…

Any actual engineer will probably find this comment painfully naive, but here we go: If it's infeasible to slow down to get into orbit or land on Pluto, what about the feasibility of designing a probe to impact Pluto at XX km/sec and survive well enough to send back data. Like, fire a (metaphorical) bullet full of scientific instruments directly into the surface of the planet. Is it simply that we have no way to buil…

[deleted]

Re: New Horizons: Nasa spacecraft speeds past Pluto

#189

Post by chasing »

chc wrote: post #183
ceejayoz wrote: post #172

Earlier quoted context omitted.

Plus, probes that far out have worse-than-dialup transmission rates. It takes 42 minutes to return a single photo from the LORRI camera. Bursting large amounts of data out in a short period of time before impact isn't feasible. http://www.planetary.org/blogs/emily-lakdawalla/2015/0130080...

I think the suggestion was to send the data after impact. I guess the idea is to basically fire a shock-absorbing crate full of scientific instruments, let the impact destroy the crate, and hope the instruments survive and get to work.

Yup, that was my idea. Or to have NH itself fire off some very tiny instruments that might weight little enough to not go off like an atom bomb when hitting the ground. A GoPro, for example. (I KNOW: NOT AN ACTUAL GOPRO. A small armored camera.) Or a thermometer.

The constraint there, though, might be designing equipment that is both very low mass and also capable of talking back to either Earth or the rest of NH as it zips away.

Re: New Horizons: Nasa spacecraft speeds past Pluto

#190

Post by dragonwriter »

scrollaway wrote: post #115
kale wrote: post #102

Earlier quoted context omitted.

What continent are you referring to that has two countries? North America has 23 countries, with the U.S.A., Canada, and Mexico being the largest countries.

Sorry, I meant two other countries and you're right; I have edited to clarify. My point was centered on borders and neighbouring countries. Do you ever see US immigration politics talking about anything else than Mexico? Canada + Mexico + the US occupy something like 95% of the landmass alone. Whenever you hear people talk about immigration in europe, we're talking about immigration from generally 5+ other countries,…

> Do you ever see US immigration politics talking about anything else than Mexico?

Yes, there's quite a lot of immigration politics around employment based immigrant visas and the dual-intent H-1B and related immigration issues, which is mostly not about Mexico.

Its true that much "immigration" discussion centers around addressing both the current population and the ongoing influx of unauthorized immigrants, where the majority are from Mexico (largely, as a result of an immigration policy based on country-of-origin based quotas, that has guaranteed that the countries that have the largest pool of otherwise-qualified applicants have the longest lines, and the fact that that Mexico, as a result, is one of the hardest places to immigrate to the US legally from, particularly in the family-based categories, while, because of geography, being one of the easiest places to immigrate illegally from.)

Post reply on HN