Astronomers Find Star Orbiting a Black Hole At 1 Percent the Speed of Light (sciencealert.com)

schwit1 writes: Astronomers have spotted a star whizzing around a vast black hole at about 2.5 times the distance between Earth and the Moon, and it takes only half an hour to complete one orbit. To put that into perspective, it takes roughly 28 days for our Moon to do a single lap around our relatively tiny planet at speeds of 3,683 km(2,288 miles) per hour. Using data from an array of deep space telescopes, a team of astronomers have measured the X-rays pouring from a binary star system called 47 Tuc X9, which sits in a cluster of stars about 14,800 light-years away. The pair of stars aren't new to astronomers -- they were identified as a binary system way back in 1989 -- but it's now finally becoming clear what's actually going on here. When a white dwarf pulls material from another star, the system is described as a cataclysmic variable star. But back in 2015, one of the objects was found to be a black hole, throwing that hypothesis into serious doubt. Data from Chandra has confirmed large amounts of oxygen in the pair's neighborhood, which is commonly associated with white dwarf stars. But instead of a white dwarf ripping apart another star, it now seems to be a black hole stripping the gases from a white dwarf. The real exciting news, however, is regular changes in the X-rays' intensity suggest this white dwarf takes just 28 minutes to complete an orbit, making it the current champion of cataclysmic dirty dancers. To put it in perspective, the distance between the two objects in X9 is about 1 million kilometers (about 600,000 miles), or about 2.5 times the distance from here to the Moon. Crunching the numbers, that's a journey of roughly 6.3 million kilometers (about 4 million miles) in half an hour, giving us a speed of 12,600,000 km/hr (8,000,000 miles/hr) - about 1 percent of the speed of light.

Comments

No it doesn't put it in bloody perspective

[blackpaw]

To put that into perspective, it takes roughly 28 days for our Moon to do a single lap around our relatively tiny planet at speeds of 3,683 km(2,288 miles) per hour

Please, spare us the bogus patronising primary school comparisons.

Re:No it doesn't put it in bloody perspective

[gravewax]

I must say that was my exact reaction to reading it, whoever wrote that really needs to get some perspective, perhaps a nice car analogy.

Re:No it doesn't put it in bloody perspective

[BeerCat]

I must say that was my exact reaction to reading it, whoever wrote that really needs to get some perspective

“Have some sense of proportion!” she would say, sometimes as often as thirty-eight times in a single day.
And so he built the Total Perspective Vortex — just to show her.

To Trin Tragula’s horror, the shock completely annihilated her brain; but to his satisfaction he realized that he had proved conclusively that if life is going to exist in a Universe of this size, then the one thing it cannot afford to have is a sense of proportion."
Douglas Adams - The Restaurant at the end of the Universe

Re:No it doesn't put it in bloody perspective

[sysrammer]

To put that into perspective, it takes roughly 20 furlongs for our Walmart Goodyear Valvoline Ford to do a single lap around our relatively tiny raceway at speeds of 4,828 m (15,840 feet) per minute.

Re:No it doesn't put it in bloody perspective

[aneroid]

Agreed!

A better way to put that into perspective would be to mention that that Moon's orbital path is 2,412,517.5 km (or 1,499,070 miles) and that if it were orbiting the Earth at the same speed as this star, it would orbit every 11.5 minutes (2,412,517.5 km / 12,600,000 km/hr), or 5 times an hour.

Re: No it doesn't put it in bloody perspective

[Anonymous Coward]

Oh, please. It's wonderful that you are able to understand this so intuitively. But who gives a shit if an accessible description is provided for less technically-minded people?

And, if you really want to go there, it should be presented in m/s anyway.

Re:No it doesn't put it in bloody perspective

[geekmux]

I must say that was my exact reaction to reading it, whoever wrote that really needs to get some perspective, perhaps a nice car analogy.

Perspective?

We still shove hundreds of horses under a car hood to measure it's power, and we love to get hopes up when discussing habitable planets that are "only" a few light years away, while describing an object traveling 8 million miles per hour using a metric invented in the 18th century.

Hope that helps.

Re:No it doesn't put it in bloody perspective

[Anonymous Coward]

How long does it take your boat to go around the harbor?
Knot furlong?

Re:No it doesn't put it in bloody perspective

[dskoll]

But how long does it take for the Moon to move the length of a football field??

Re:No it doesn't put it in bloody perspective

[Anonymous Coward]

It depends on how many timeouts are called and how many commercial breaks occur.

Re: No it doesn't put it in bloody perspective

[Anonymous Coward]

I think the point is that this description DOESN'T help. It is just some random "fact" meant to make retards feel like they now know something. It takes me 20 minutes to get to work... its 15 miles. This is way faster. Does that help?

Re: No it doesn't put it in bloody perspective

[Anonymous Coward]

But due to time dilation, from that star's perspective the metric system was only invented in the 19th century.

Re:No it doesn't put it in bloody perspective

[Anonymous Coward]

Wow, that would suck, 5 tide shifts an hour, or considering the menstrual cycle likely evolved its period from the Moon... nm, I don't want to thing about it,

Re:No it doesn't put it in bloody perspective

[apoc.famine]

Now I want to spin up a fluid dynamical model to model the tides from that! I wonder what the hell that would look like? Guessing lots of oscillating tides with an occasional super-tide where some of the waves stack.

Re:No it doesn't put it in bloody perspective

[Anonymous Coward]

I can envision a B-rated sci-fi movie where some evil supervillain has a series of beefs against a number of coastal cities.

Re:No it doesn't put it in bloody perspective

[GNious]

We still shove hundreds of horses under a car hood to measure it's power

To be fair, civilized countries are slowly changing to report a car's power output in Watt (kilos of them, even)

Re:No it doesn't put it in bloody perspective

[RockDoctor]

The Moon would be ripped apart by the stresses produced in accelerating it towards the Earth. Your model wouldn't last long - probbly only a short fraction of an orbit.

But why do you need a fluid dynamics model? Consider a rock (a "test particle") on the far side of the Moon, and the forces on it - it's gravitational attraction by the Moon ; ditto from the Earth ; it's inertia. Will the forces on the test particle push it into the Moon, or away from the Moon? Repeat for next particle, with a slightly smaller Moon mass. You're treating the Moon as a strengthless agglomeration of weakly-interacting particles - which is one way of looking at a fluid.

Re: No it doesn't put it in bloody perspective

[Anonymous Coward]

Ok ok let's not do the Kessel run in less than 12 parsecs...

Simple question

[Anonymous Coward]

I have a simple question. How does this affect anyone? Can anyone explain how a distant black hole and star that humans will never visit, affects anyone at all? Why are tax dollars funding useless research like this when the money could fund our military or cutting taxes on our businesses. This research is even more wasteful than the EPA, and useless work like this is exactly what's wrong with America. The academics sit in their ivory tower and do worthless research like this while blue collar workers are put out of jobs. Can anyone explain to me how this affects normal people like me? I think not, but I expect I'll be censored by the moderators so they can avoid answering the tough questions.

Re: Simple question

[Anonymous Coward]

We spend $700 000 000 000 a year on the military and yet u want to spend MORE? R u mad?

Re:Simple question

[SiggyRadiation]

You might be right. This might be a lucky find though in a larger project that does result in tangible benefits to society. And then I’m not against spending some more time to research it.

Your broader question might be about basic research: https://en.wikipedia.org/wiki/.... Basic research might not result in direct benefits, but a better understanding of natural phenoma can actually result in immense benefits.

In this case, for example, this might be the first object that we discovered that actually travels at speeds (in orders of magnitude) close to the speed of light. This could, for example, in the long run improve our understanding of relativity, properties of light and electromagnetism, etc.

If you realise how close some of our everyday technologies such as microprocessors, WiFi, etc. actually are operating close to the absolutes borders of physics, then you’ll understand that things we learn from basic research is the only way left to improve those technologies.

So, this finding *might* lead to some new understanding that *might* lead to new technologies that *might* lead to incredible new benefits to society. The only problem is, you don’t know in advance which research is the one with the big benefits. Spread your bets.

Re:Simple question

[Anonymous Coward]

Curious why a team of researchers from Australia (ICRAR) should pay for your tax cuts and military. Or were you asking the geopolitical education normal people get in middle school?

Re:Simple question

[hackwrench]

No, I see the question as more along the lines of how the people setting the course for society don't seem to be aware that wide swathes of people are hurting. Maybe that pain is inevitable and part of the current human condition, but maybe if our attentions are redirected upon it, maybe something might be able to be done. Maybe we are already doing all that can be done, but little is being done to reassure those that are hurting of that fact.

Re:Simple question

[Anonymous Coward]

Your point is clear, however, your dichotomy raises questions, even those of your motives.

See, putting money into millitary is actually, partly, the space program research that is being discussed in TFA. So when you say fund military, this is already being done. I would say that, even though funding war machine brought a lot of benefits to human race, it was just as a side effect. Ultimately, if the primary goal of war funding is reached, which is exterminating some population, and rendering our habitat in catastrophic state, this should be understood that it is not worth it. We, any gov, should instead fund research which would help humanity reach other planets, make so that nobody dies of some deseases or bacterias. Think about having your parents not dieing for longer. Think about those who go prematurely because of cancer. There are many thing that are worth working on.

As for the benefits of studying celestial bodies and whatnot, I would say that a lot of discoveries are done unconspicously while doing some "unworthy" study or research. In other words, we do not know what we do not know. And nobody knows how events will play out in future. And therefore who are you to say, "do not do not do this, because it is not worthy". History tells that it is worth doing reasearch in many different fields, even when benefits are not clear on what this research will bring.

Re:Simple question

[Anonymous Coward]

It seems pretty obvious that more U.S. tax dollars should've been spent on that guy's lousy education.

Re:Simple question

[SiggyRadiation]

You have to find a good mix in investing in the future and solving everyday problems *now*. And it’s very hard to make any argument about investing in the future to somebody who’s hurting today. You’re never going to win that debate, rationally or emotionally.

I read somewhere (http://www.airspacemag.com/daily-planet/jfk-and-the-moon-180947824/) that Kennedy, before deciding on using project Apollo as a technological showcase for America, actually considered a large-scale desalination project to help Third World nations.

What if Kennedy had chosen the latter option? How would the world have evolved since then? An abundance of water and food in Africa but no internet and supercomputer in everybody’s pocket? Or would the desalination have contributed little and computers evolved just the same? Nobody's arguing about his choices back then because we're all happy his mission succeeded.

In the end, again, it’s about finding the right balance in investing in every day problem solving *and* investing in things that help us forward in the future.

Re:Simple question

[Anonymous Coward]

I sincerely hope you're joking.

Practically everything around you was made possible by scientific research. If you think that's what's wrong with America, you could always move to Syria where I'm sure there's less wasteful spending on science and much more spent on military.

Re: Simple question

[Anonymous Coward]

Wrong. Obama spent all that money on sand n1ggers in ISIS and funded terrorists and extremists throughout the world. And you've never seen a dime of return on that.

Re:Simple question

[Xenographic]

It provides insight into the laws of physics. We couldn't do the engineering we do without the basic science to back it up.

I'm sure sure that relativity seemed useless at first, but our GPS devices wouldn't work right if we didn't understand it.

Re:Simple question

[sysrammer]

I have a simple question. How does this affect anyone?

Consider it the butterfly wings fluttering on the other side of the world.

Re:Simple question

[sysrammer]

Careful, your post makes too much sense. It may be moderated out of existence by the alt.truthers.

Re:Simple question

[ArylAkamov]

You might as well ask why it matters if we believe the earth is flat or not.

Re: Simple question

[Anonymous Coward]

Well to the guy in Kenia running after a chicken at 1 billionth of the speed of light, it matters whether the earth is flat, since it would get progressively more difficult if the earth really was shaped like a soup bowl.

Re:Simple question

[reboot246]

Spending on science benefits everybody. Even the military benefits from such research. Where do you think all of those advanced weapon systems come from, lucky guesses?

Re:Simple question

[Anonymous Coward]

We can study relativity and gravity with it.
https://en.wikipedia.org/wiki/Tests_of_general_relativity#Post-Newtonian_tests_of_gravity

A new theory of gravity has a potential to change the world.

Re:Simple question

[Plus1Entropy]

I agree, we should spend the tax money on those blue collar workers who have been put out of their jobs. Maybe you should write a Manifesto?

Re:Simple question

[eggstasy]

Fast forward 1000 years. Your flying car is running on essentially free energy thanks to its "gravity engine" (tm) which draws upon Physics so extreme, that to become aware them, you would have had to setup something as massive as a white dwarf orbiting a black hole, and study it for 30 years, before being able to reproduce this phenomenon in laboratory conditions, let alone miniaturize it.

Re:Simple question

[Anonymous Coward]

it encourages the tiny proportion of the population who believe staring up into the sky while murmuring "billions and billions and billions and" is fulfilling.

Re:Simple question

[Sique]

Even solid-state physics seemed esoteric at first. Why try to find out how electrons move between atoms in crystals that are not very good conductors, but quite bad isolators as well? And suddenly: transistors!

Questioning the reason behind research is partly envy (why don't I get this cool equipment to play with?), partly missing imagination (why can't I think of anything this might be useful for?) and partly missing scientific education (why do I take everything I use today as a given without ever wondering how they work?).

Re:Simple question

[Anonymous Coward]

Easy.

No-one knows where the next breakthrough will come from, so we let researchers study things they personally really want to learn, in the knowledge that some of them will discover things that are valuable.

The basic theory and implementation used in all wifi networks came about because of basic radio astronomy research - the very thing you're criticising - done by radio astronomers at CSIRO in Australia.

The world wide web came about as a side effect of basic physics research at CERN. All the money ever spent on CERN is far outweighed by the value and efficiency to commerce that the web has provided.

The foundations of computer science came about through fundamental research in mathematics and logic. No-one could have predicted that.

The foundations of evolutionary science, with all its benefits in agriculture, came about through a scientific voyage in the age of wind powered ships.

Lasers, the foundation of modern fibre optic communications, and of materials science, and manufacturing, came about through fundamental research in physics. Who could have known?

The foundations of modern genetic manipulation came about through research into bacteria in hot springs. No-one predicted that.

I could go on.

None of these things could have been predicted in advance.

If you insisted that we only fund things that are of immediate benefit, we'd all still be wearing raw animal skins and communicating by banging rocks together.

The costs of all the worlds unplanned fundamental scientific research are nothing next to the unknown benefits that some unknown researcher is coming up with today, doing something that you'd describe as wasteful and of no known use.

Re: Simple question

[Anonymous Coward]

No, he's afraid that stinky Mexicans might walk hundreds of miles through desert so they can illegally enter the country and knock on his door offering to cut his grass for $10 less than the neighbor's kid charges.

Re:Simple question

[TheRaven64]

What if Kennedy had chosen the latter option? How would the world have evolved since then? An abundance of water and food in Africa but no internet and supercomputer in everybody’s pocket?

That's not very likely. The Internet came from an ARPA project that was unrelated to the space program. The space program contributed a little to the development of computers, but it was just a single customer for computers - the DoE was a much larger one, even just counting US government spending. The main outcomes of the space program that are relevant for smartphone / Internet development were in satellite technology, in terms of GPS and communication satellites and could still have been developed with a much smaller budget and without the Moon mission. The main transferable outcomes from the space programme were in materials science.

Re:Simple question

[silentcoder]

I recently saw an American claim that "the moon landing program did everything with a commodore 64 and hasn't contributed anything since". Which, if it was true, would mean they'd unlocked the secrets of time-travel considering that the Appollo program ended in 1972 and the first C64 wasn't actually built until 1980 - not to mention the Commodore64 was made-in-Britain: hardly an American contribution, when it was first unveiled American companies were flabbergasted at what it offered for 500-dollars, a price they couldn't come close to profitably matching. The answer, by the way, was vertical integration: Commodore owned their own Chip-FAB and this meant they could easily test multiple chip designs quite cheaply and iteratively develop their chips because they could quickly make one in-house to see how it performed. Exactly the OPPOSITE of the current model of "outsource everything and only focus on your core business".

Either way - the claim tells you something about the level of understanding many American's have off the issues they form opinions on - and even the latter part of the claim is flagrantly untrue. NASA has, in act, contributed greatly to computer science - among the most noteworthy achievements was the invention of clusters.

Re: Simple question

[PoopJuggler]

Yeah, when has science ever done anything to help anybody?

Re: Simple question

[Anonymous Coward]

This isn't even US astronomers, dipshit.

Re:Simple question

[TheRaven64]

among the most noteworthy achievements was the invention of clusters

If that's among their most noteworthy achievements, it doesn't say much. Clusters were a pretty obvious development: they're basically an approximation of existing supercomputer designs using commodity hardware, and come with all of the limitations that you'd expect. If NASA hadn't invented them, someone else would have done, just as multiple people have replicated the high-availability features of mainframes on commodity hardware with VMs.

Re:Simple question

[silentcoder]

No actually - when they did it that was not where anybody else was heading. The supercomputing world was still ruled by Seymore Cray who was convinced that clusters could never compete with massive-chip systems in either cost or power.
And he still ruled the market.

NASA however, could not afford his computers anymore - and you know what they say about necessity and invention. So while others had theorised clusters before - nobody had tried to solve the issues of how to practically BUILD a super-computing cluster because the only game in the supercomputing town wanted none of it. NASA made them work - with beowulf - and it's noteworthy for it's impact (which was enhanced because NASA open-sourced the technology). Within two years the same idea was being used for redundancy and high-availability designs (expanding on the original 'build a cheap supercomputer' concept.
Every cluster in every data center in the world today is a direct descendent of NASA's design. It's a cornerstone of 21st century computing - and in the research side it's how EVERY super-computer is built now. But NASA pioneered it - when every expert thought it couldn't be done.

Re:Simple question

[dskoll]

Nicely played! Really elegant sarcasm there.

Re:Simple question

[TheRaven64]

Every cluster in every data center in the world today is a direct descendent of NASA's design

There are very few clusters in datacentres. Most distributed compute jobs in datacentres use things like MapReduce or similar, which (unlike Beowulf) are specifically designed around high-latency, high-bandwidth interconnects. There are clusters in supercomputing centres. They overwhelmingly use MPI, which predates NASA's Beowulf system by three years and was an integral part. MPI was developed with NSF and ARPA funding. NASA built a famous commodity system using it, but they weren't the first, nor were they the only group doing so. The other core part of Beowulf, PVM, is even older (1989) and is also not a NASA technology.

Beowulf definitely succeeded in becoming a Slashdot meme, but its impact on cluster computing was far less. I've worked on a number of systems that people referred to as 'beowulf clusters,' but not a single one was actually running the Beowulf software.

Re:Simple question

[Anonymous Coward]

I have a simple question. How does this affect anyone? Can anyone explain how a distant black hole and star that humans will never visit, affects anyone at all?

Right?! I wish they'd spend money researching and building a time machine... then we could send people like you back 100,000 years so you could live the science free life you so long for.

Re:Simple question

[Anonymous Coward]

the first C64 wasn't actually built until 1980

MOS completes development of the 6510 Central Processor and chip set in 1980. In Novemver 1981, Jack Tramiel tells the engineers to make a home computer to show at CES in 6 weeks. 5 Prototypes are assembled in December 1981, in January 1982 the operating system from the VIC-20 is ported and the C64 was announced at CES.

Commodore64 was made-in-Britain: hardly an American contribution

Do you have a citation for that?

The team that constructed C64 consisted of Yash Terakura (Commodore Japan), Bob Russell (USA), Bob Yannes (USA) and David A. Ziembicki.
MOS Technologies was based in Norristown, Pennsylvania.

Re:Simple question

[catmistake]

I've worked on a number of systems that people referred to as 'beowulf clusters,' but not a single one was actually running the Beowulf software.

I see... so that's not a car, it's an automobile!!

I think you pedanted yourself right out of making any sense. What you describe are indeed Beowulf clusters.

No particular piece of software defines a cluster as a Beowulf. Beowulf clusters normally run a Unix-like operating system, such as BSD, Linux, or Solaris, normally built from free and open source software. Commonly used parallel processing libraries include Message Passing Interface (MPI) and Parallel Virtual Machine (PVM). Both of these permit the programmer to divide a task among a group of networked computers, and collect the results of processing. Examples of MPI software include OpenMPI or MPICH. There are additional MPI implementations available.

Re:Simple question

[david_thornley]

Sure, we can do more. However, cutting basic research out of the budget isn't going to free up anywhere near the needed money. For that, we'd need to cut into a reasonably large part of the budget, or raise taxes, or go deeper into debt.

Also, lots of the people hurting aren't going to be helped by throwing money at them. There has been a structural shift in the economy since the 1950s, and a lot of blue-collar jobs are simply not coming back. The US still makes a very large amount of stuff, but with a much smaller number of workers. It will never again be possible to count on earning a good living with a strong work ethic and little skill. To move on, people need to realize this and act accordingly, picking up new skills.

Re:Simple question

[hackwrench]

>Also, lots of the people hurting aren't going to be helped by throwing money at them.

Which is why I learn about my medical situation, which I have to do on my own, because the people who contribute to my care can't provide any useful in's, relying on "Do you have any questions?" No, but I have keywords like vitamin D deficiency, near diabetic, etc. Well at least they have recently switched over to a computer system that allows me to access the lab tests they've run on my blood, but the system is nowhere near as good as it could be.

Re:Simple question

[TheRaven64]

So, what you're saying is, NASA's biggest contribution to computer science was giving a name to a combination of software written by other people and pre-dating NASA's involvement?

Re:Simple question

[sysrammer]

Nope. He's not saying that. You are.

Note: I think this is one of the "Logical Fallacies", folks, but I don't know which one. Can anyone out there help me? (Yah, I could do it, but I haven't had my coffee yet, so...)

Re: Simple question

[sysrammer]

Well to the guy in Kenia running after a chicken at 1 billionth of the speed of light, it matters whether the earth is flat, since it would get progressively more difficult if the earth really was shaped like a soup bowl.

But what if the bowl was inverted? Didn't think of that, did you?

You have to think outside the bowl, sometimes.

Re:Simple question

[TheRaven64]

He is claiming that Beowulf clusters are one of the biggest contributions to computer science by NASA. Beowulf clusters are commodity hardware combined with open source software that predates NASA's involvement. NASA's contribution was to assemble the bits and give it a name. They weren't the first organisation to build a cluster using that software. There was almost nothing new in the software, network topology, or hardware in their design, yet this is what he's claiming as evidence of NASA's great contributions to computer science.

How does this affect me

[Anonymous Coward]

And how was my tax money used in this pursuit?

Re:How does this affect me

[war4peace]

Ok, I'll bite.
Most of tax money spent by your government will never benefit you directly. By "most" i really mean ALL of it, except tiny, tiny fractions of a percent.
This includes roads you'll never drive on, parks you'll never visit, government building you'll never step foot into, hospitals you'll never get treated at, employees you'll never need, etc., etc.

But getting back to the issue at hand, if you care looking at the linked documents from TFS, you'll see the contributors' universities:

1 Department of Physics, CCIS 4-183, University of Alberta, Edmonton, AB T6G 2E1, Canada
2 Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA
3 International Centre for Radio Astronomy Research - Curtin University, GPO Box U1987, Perth, WA 6845, Australia
4 Columbia Astrophysics Laboratory, Columbia University, New York, NY, USA
5 Department of Physics, Texas Tech University, Lubbock, TX, USA
6 School of Physics and Astronomy, University of Southampton, Southampton, UK
7 Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA
8 NASA Goddard Space Flight Center, Greenbelt, MD, USA

#1, #3 and #6 are not USA-based.
#2, #4, #5 and #7 are universities which are most likely privately funded.
That leaves #8 as the only gov't funded location.

I'd say your tax money are pretty safe from this and would very likely be spent on genuinely useless endeavors which would never be of help to anyone.

Re: How does this affect me

[Anonymous Coward]

I don't pay tax. The little people pay tax. So maybe it does affect you only?

Re:How does this affect me

[Plus1Entropy]

Rather spend my tax money on this than building fighter jets that can't fly in the rain.

Re:How does this affect me

[Anonymous Coward]

I'd say your tax money are pretty safe from this and would very likely be spent on genuinely useless endeavors which would never be of help to anyone.

You just described the entire federal government. So let's pare it down to a minimum and give the money back to the people.

Or do you like giving Cheeto Hitler that much money every year? If you think the federal government should still exist in its present size, then you are colluding with Trump.

Re:How does this affect me

[silentcoder]

Assuming you're American - it wasn't, since this research was done by Australian scientists.

Re:How does this affect me

[war4peace]

Sadly for you, I live in a different country, on a different continent.
Still, politicians here are equally bad, if not worse.
It's the same everywhere.

Re:How does this affect me

[Bob the Super Hamste]

#2 (Michigan State University, East Lansing) and #5 (Texas Tech University, Lubbock, TX) sure sound like public schools. In looking them up they are actually publicly funded universities.

Re: How does this affect me

[Anonymous Coward]

Wait - isn't trump the guy trying to axe half of the federal government?

Re:How does this affect me

[war4peace]

#2 had sizeable Endownment during the last couple decades: https://en.wikipedia.org/wiki/...

Also #5 had endownment passing a billion dollars in 2014.

So maybe, just maybe the research mentioned in TFS was funded through these endowments :)

Re:How does this affect me

[Namarrgon]

Alternatively, it's just as valid to say that GP's entire tax contributions to date covered the cost of a few metres of road near his house, and that everywhere else he/she drives, visits, steps foot in, gets treated at, etc, are all paid for by someone else. Including this research.

Re:How does this affect me

[war4peace]

I'd use "similarly" instead of "alternatively", because both variations prove the same point.

Re:How does this affect me

[syntotic]

It is the TOKEN act what matters. A dispute with Mexico over immigration is affecting research funding some way. It is not good when the mass will only understand RESEARCH BUDGET CUTS. Though it could be media that is not fully professional on this, and why am I making this comment in a thread for astrophysics?

Its a test to see how many people

[future assassin]

ask this question "Why are tax dollars funding useless research like this when the money could fund our military or cutting taxes on our businesses." Seems this time Slashdot is the location of this black hole.

Re:Its a test to see how many people

[tonywestonuk]

Tax's dont fund spending. Haven't since we came off the gold standard. Instead, this research gives jobs to people qualified to do so, extending human knowlege.

With the scale of unemployment, would you rather they sit on social?

http://www.pragcap.com/ama/wha...

Re:Its a test to see how many people

[Anonymous Coward]

Yes, you've nailed the only two choices. (1) pay people too much money to do something useless or (2) put highly educated and highly skilled people on the bread line because they are incapable of doing anything else.

Your link, by the way, is quite hilarious. Banks "destroying" repaid loan money. Yes, I'm sure that's happening. Absolutely.

Please use proper units

[140Mandak262Jamuna]

Km and miles are useless in visualizing this. Please tell me how many schools buses lined up end-to-end will cover the distance between them.

Re:Please use proper units

[Anonymous Coward]

Regular or handicapped?

White-Yellow Whip Star?

[Anonymous Coward]

With the tidal forces this star has to be shaped like a big bent line whipping through space. I imagine pretty massive to keep a elongated core at critical mass as it whips around this star. It might be able to turn even a red giant into a super long white dwarf by stretching out the layers and surface area.

Re:White-Yellow Whip Star?

[RockDoctor]

If it's a white dwarf (WD), it's going to have an internal strength (stiffness) somewhere well above that of steel, but more importantly, very strong forces pulling it's material back together.

My non-calculated estimate on the WD's shape is that it would be a prolate ellipsoid of rotation, with the long axis pointing towards the primary. Not necessarily directly at the primary - there might be some displacement due to the residual rotational angular momentum of the WD.

Nobody's arguing about his choices back then becau

[hackwrench]

Or maybe nobody's arguing about his choices back then because they don't teach anything about his choices in school, or even if they did, well that's all in the ancient past and people are wondering about whether they will see tomorrow, or whether they will like it when it comes. I have health problems, and I am hurting, but I am also fairly intelligent. I know to figure out that they've come out with the Samsung J3 Emerge, which has the bare minimum to do some sort of VR and to find it on eBay for my carrier for $75 and a cheap plastic face-box-lens device, and show it to the people from the company that get paid by the state to assist me. The temporary guy that came in to assist me because a coworker died in a car accident and they had to shuffle some people around including my usual assistant, said, that's cool and he wants to buy something like it for his son, and I told him that i got it together for very inexpensively and that if he looks into it he can figure out what needs to be bought.

It seems to me that the reason some people aren't arguing about his choices is because they are dealing with very big problems and situations they are facing in the here and now. But what do I know? I'm just a guy who's hurting.

Gravity wave losses?

[K. S. Kyosuke]

I'm wondering about how quickly such a system loses energy. In general relativity, not even Keplerian orbits should be stable.

Re:Gravity wave losses?

[Anonymous Coward]

If only our new gravitational wave sensors were operational, we could watch this sick couples dance moves of death in detail.
They play a dangerous game our there on the ice of space.

Questions...

[ZeRu]

I wonder, how long it will take for the star to fall into the black hole? Or it will completely evaporate sooner? And how the orbit looks like?

Re:Questions...

[Anonymous Coward]

Probably more time than it takes the project to have its budget cut.

Re:Questions...

[Anonymous Coward]

The orbit looks like a big glowy thing going around an even bigger dark thing really, really fast.

Money blackhole!

[Anonymous Coward]

We are pissing away money on this trivia!! How cares!?!

Cut NOW!

trolL

[Anonymous Coward]

They learn from our ofone single puny OF AMERICA) is the reciprocating rules are This Vary for different an operating system real problems from one folder on questions, then maggot, vomit, shit stupid. To the Juggernaut either Corporate polite to bring though, I have to before playing to Used to. SHIT ON Ass until I hit my that they sideline Of its core some of you have offended some proje3t somewhere God, let's fucking Decentralized As fittingly Playing so it's [gay-sex-access.com]? BSD had become BSD machines completely before GNAA on slashdot, eulogies to BSD's I've never seen To die. I will jam crisco or lube. Preferrably with an NetBSD user

earth is small

[Anonymous Coward]

Heh, Ganymede is about 1 million km from Jupiter, and it takes 7 days to complete its orbit. For the black hole, it is half an hour. IO takes 1.8 days to orbit Jupiter, and it is about as far away as earth's moon. Earth's moon takes about 28 days to orbit Earth. Makes this earthling feel small.

Re:earth is small

[Anonymous Coward]

1 million km
1 million thousand meters
the cardinal failure of the metric system is highlighted herein

Wrong units of measurement

[Harold Halloway]

Here in the UK, our press uses the following units of measurement:

Distance: buses parked end-to-end.
Weight: elephants.
Area: Wales.

Please amend the article appropriately.

Re:Wrong units of measurement

[Anonymous Coward]

> Area: Wales.

That's "whales" in US English.

Re:Wrong units of measurement

[mjwx]

Here in the UK, our press uses the following units of measurement:

Distance: buses parked end-to-end.
Weight: elephants.
Area: Wales.

Please amend the article appropriately.

Are they an American or European bus.

Re:Wrong units of measurement

[xession]

Slashdot rule# 2 - if you can't complain about the topic, complain about the measurement units.

Re:Wrong units of measurement

[Anonymous Coward]

Finally a fellow I can understand!

I measure my sleep-time in units of:
* how often the kids woke me up at night, (a short & frequent increment).
* how often the pets jumped onto my chest or groin, (a broader increment).
* how often I slept in past dawn and woke to the scent of breakfast being prepared for the house, (the longest increment).

Re:Wrong units of measurement

[Anonymous Coward]

Are they an American or European bus.

No.

Re:Wrong units of measurement

[Anonymous Coward]

In silicon valley, we use a data bus.

Re:Wrong units of measurement

[thegarbz]

Blue wales or humpback wales?
And when would a British person ever see wales? Water is cold and wet so they don't go in it.
Why would a British person want to see wales too.

Re:Wrong units of measurement

[clovis]

Slashdot rule# 2 - if you can't complain about the topic, complain about the measurement units.

Why on earth would you use a hyphen in that sentence?

A vast black hole?

[Bill Hayden]

Astronomers have spotted a star whizzing around a vast black hole

Black holes are the antithesis of vast. They have no size whatsoever.

Re:A vast black hole?

[Anonymous Coward]

The size of a black hole is the size of its event horizon and that is typically the size of a planet or larger.

Re:A vast black hole?

[Anonymous Coward]

Black holes are the antithesis of vast. They have no size whatsoever.

I realise you're trying to be pedantic, but you're not trying hard enough. When we talk about Black holes, we mean the phenomena. As such, some black holes can be vast, since we consider the "hole" to be defined by its Schwarzschild radius. Now, if you're talking about the singularity at the centre of a black hole, that would be another matter.

Re:A vast black hole?

[abies]

From https://en.wikipedia.org/wiki/...
"Note that a black hole is a spherical region in space that surrounds the singularity at its center; it is not the singularity itself"

So 'black hole' has the size, which is directly related to its mass. You can compute it here
https://www.vttoth.com/CMS/phy...

Re: A vast black hole?

[Anonymous Coward]

Another matter. Clever.

Re:A vast black hole?

[Bengie]

They're at least 1 cubic plank-length. Not to mention the notion of a true singularity is probably wrong. There's a lot of magic hand-waving to think of a blackhole as a true singularity. Some how the blackhole can grow, yet nothing can fall past the event horizon in any frame of reference, and all of the information is at the "center"? What? How does the information get to the center if by definition it can not?

The more recent idea that a blackhole is just the highest density of information with the information being stored on the surface, just above the theoretical event horizon, is much simpler and agrees or at least does not create a bunch of paradoxes.

Re: A vast black hole?

[Anonymous Coward]

Thanks. You may have been the only one that noticed.

Proverbial back of the envelope stuff...

[Anonymous Coward]

From the orbit radius and period we can work out the mass of the black hole is 1.8E+32 kg, or about 90 solar masses. Hence it's Swartzchild radius is roughly 300 km.

The Roche limit for this body depends on the density of the satellite, e.g. for a planet like Earth it'd be 2.5 million km and we'd be so much space jam before we ever got as close.

Fortunately white dwarf stars are pretty compact (approx 1 billion kg/m3), so their Roche limit is a snug 44,000 km.

Must be a hell of a view!

Tidal force difference

[dackroyd]

The difference in force from gravity on the near side of the star compared to the far side must be enormous.

Does anyone know how close this star is to its Roche limit, or equivalent for gaseous bodies?

Re:Tidal force difference

[Bob the Super Hamste]

this is why I like /., now I know what the Roche limit is.

Re:Tidal force difference

[edmor]

You're right. The tidal force must be huge. Especially since the orbiting star is losing mass to the black hole it cannot be in a perfectly circular orbit but must be somewhat eccentric. And those massive changes in gravitational forces it's subjected to are cycling over the space of just a few minutes! To add to the question about how close the star is to the Roche limit, does anybody know the mass of the black hole it's orbiting? How close is it to the black hole's event horizon? It would be very cool if the star is hurtling around the black hole at 1% speed of light within grazing distance of the event horizon.

Re:Tidal force difference

[Anonymous Coward]

I haven't done full calculation, but it seems that tidal force is not strong enough even to cause the mass loss that we are seeing. The BH is assumed to be low mass (of order 10 times the mass of sun) and it cannot exert enough gravity to rip apart WD from a distance of 1,000,000 km. Either BH is bigger or distance has to be lower.

Re:Tidal force difference

[Anonymous Coward]

> Does anyone know how close this star is to its Roche limit, or equivalent for gaseous bodies?

White dwarf stars are very dense (~1 billion kg/m3) so their Roche limit is very close in to the black hole (~45 thousand km). For a planet like the Earth (density ~5500 kg/m3), the Roche limit is (~2.5 million km), ice giants like Neptune would shred at about 3.7 million km, a gas giant like Jupiter loses it at 4 million.

> does anybody know the mass of the black hole it's orbiting?

About 90 solar masses.

> How close is it to the black hole's event horizon?

Not close, for that mass of black hole the Swartzchild radius is about 270 km.

The star should be radiating

[Anonymous Coward]

gravity waves. There should be a very slight decrease in the radius of its orbit.

Max speed to which solid object can accelerate?

[WetCat]

Everybody knows that only photons can reach the speed of light in vacuum.
What happens with a solid object if we are starting to accelerate it?
To what speed can it accelerate without losing its physical parameters (by ionization, atomic reactions etc)?

Units of measure

[Anonymous Coward]

How many Kessel Runs and parsecs does that equal?

Re: Max speed to which solid object can accelerate

[Anonymous Coward]

Why don't you take a physics course and find out? Or google it?

General relativity tells you what happens as velocity approaches the speed of light.

To what speed can it accelerate without losing its physical parameters (by ionization, atomic reactions etc)?

None of this happens in a vacuum.

In the real world with objects and particles smashing into things, mechanical and aerospace engineering often deals with these issues, and materials engineering is the discipline that tackles the issues head on.

E.g., on the Space Shuttle, the thermal tiles would ablate during reentry (burn off, essentially, into plasma).

Only 1% speed of light? That sucks!

[burhop]

I was thinking, "this is great! I can go hang out there for a few days and come back to Earth years from now".

Unfortunately, 1% only gives a time dilation of about 1.01

    t' = t/sqrt(1 -v2/c2)

Really, you have to get to well over 90% the speed of light if you want Trump's presidency to be over in a few hours.

But Not the Fastest Star Known!

[careysub]

That would be S0–2, a star orbiting Sagittarius A* - the gigantic black hole at the Milky Way's center.

S0-2 has a longer orbit than 47 Tucanae X9, because it is highly elliptical, but at closest approach to Sagittarius A* is reaches 5000 km/sec. The speed of 47 Tucanae X9 is 3500 km/sec.

I'm dissappointed

[OhSoLaMeow]

This has been out for twelve hours and even though TFS says "whizzing around a vast black hole", not ONE comment about "your Mom" or "Uranus"?

Are we getting THAT old?

Re: Max speed to which solid object can accelerate

[angel'o'sphere]

Mass does not lose its "physical parameters"-

But the closer it comes to the speed of light the heavier it gets, it gains mass. That means, to accelerate it further, you need more power, but mostly you will again: just increase its mass and not its speed. Hence it can not reach the speed of light.

However in labs we accelerate electrons or protons to something like 99.9% of c.

Re:Only 1% speed of light? That sucks!

[Anonymous Coward]

Are you remembering to account for the time dilation induced by the gravity of the black hole, as well?

Time dilation

[Waccoon]

What kind of time dilation effects are we talking?

Re: Max speed to which solid object can accelerate

[Anonymous Coward]

It only gains mass if you are hellbent on stating that E=Mc^2. Since the star is not at rest, it would be better to state that E^2 = (M^2 c^4) + (p^2 c^2). That way, as the momentum (p) changes, the energy of the object changes the way you expect; but you don't have that concept of "things have more mass when they go fast".

And still my g/f complains I'm too fast ;)

[TheGrimmReaper]

1% the speed of light eh? and yet my g/f complains I go to fast ;)

Re: Max speed to which solid object can accelerate

[WetCat]

Mass doesn't lose its "physical parameters"e, true. But a physical object does! I have a spaceship. It is accelerating by some means. My question is: at what speed approximately it becomes a "set of protons and electrons" instead of its normal shape? To what speed it can accelerate without losing its shape?

Re: Max speed to which solid object can accelerate

[angel'o'sphere]

My question is: at what speed approximately it becomes a "set of protons and electrons" instead of its normal shape? At none?
To what speed it can accelerate without losing its shape? As close to c as you want, why do you think your ship would lose its shape?