'Heartbeat stars' unlocked in new study

October 24, 2016 by Elizabeth Landau, Jet Propulsion Laboratory
This artist's concept depicts "heartbeat stars," which have been detected by NASA's Kepler Space Telescope and others. Credit: NASA/JPL-Caltech

Matters of the heart can be puzzling and mysterious—so too with unusual astronomical objects called heartbeat stars.

Heartbeat stars, discovered in large numbers by NASA's Kepler space telescope, are binary stars (systems of two stars orbiting each other) that got their name because if you were to map out their brightness over time, the result would look like an electrocardiogram, a graph of the electrical activity of the heart. Scientists are interested in them because they are binary systems in elongated elliptical orbits. This makes them natural laboratories for studying the gravitational effects of stars on each other.

In a heartbeat star system, the distance between the two stars varies drastically as they orbit each other. Heartbeat stars can get as close as a few stellar radii to each other, and as far as 10 times that distance during the course of one orbit.

At the point of their closest encounter, the stars' mutual gravitational pull causes them to become slightly ellipsoidal in shape, which is one of the reasons their light is so variable. This is the same type of "tidal force" that causes ocean tides on Earth. By studying heartbeat stars, astronomers can gain a better understanding of how this phenomenon works for different kinds of stars.

Tidal forces also cause heartbeat stars to vibrate or "ring"—in other words, the diameters of the stars rapidly fluctuate as they orbit each other. This effect is most noticeable at the point of .

"You can think about the stars as bells, and once every orbital revolution, when the stars reach their closest approach, it's as if they hit each other with a hammer," said Avi Shporer, NASA Sagan postdoctoral fellow at NASA's Jet Propulsion Laboratory, Pasadena, California, and lead author of a recent study on heartbeat stars. "One or both stars vibrate throughout their orbits, and when they get nearer to each other, it's as though they are ringing very loudly."

Kepler, now in its K2 Mission, discovered of heartbeat stars just in the last several years. A 2011 study discussed a star called KOI-54 that shows an increase in brightness every 41.8 days. In 2012, a subsequent study characterized 17 additional objects in the Kepler data and dubbed them "heartbeat stars." To characterize these unique systems, further data and research were required.

Shporer's study, published in the Astrophysical Journal, measured the orbits of 19 heartbeat star systems—the largest batch ever characterized in a single study. The authors followed up on known heartbeat stars, previously identified by the Kepler mission. Specifically, they used an instrument on the W.M. Keck Observatory telescope in Hawaii called the High Resolution Echelle Spectrometer (HIRES), which measures the wavelengths of incoming light, which are stretched out when a star is moving away from us and shorter in motion toward us. This information allows astronomers to calculate the speed of the objects along the line of sight, and measure the shape of the orbit.

"We found that the heartbeat stars in our sample tend to be hotter than the sun and bigger than the sun," Shporer said. "But it is possible that there are others with different temperature ranges that we did not yet measure."

Study authors also postulate that some of heartbeat stars could have a third star in the system that has not yet been detected, or even a fourth star.

"The mere existence of heartbeat stars is a bit of a puzzle," said Susan Mullally (formerly Thompson), a SETI Institute scientist working for the Kepler Mission at NASA's Ames Research Center in Moffett Field, California, and co-author of the study. "All the tidal stretching of these heartbeat stars should have quickly caused the system to evolve into a circular orbit. A third star in the system is one way to create the highly stretched-out, elliptical orbits we observe."

Researchers are currently pursuing follow-up studies to search for third-star components in heartbeat star systems.

"We look forward to continued collaboration between ground and space observatories to better understand the complex inner workings of heartbeat stars," Shporer said.

Explore further: Hubble finds planet orbiting pair of stars

More information: Avi Shporer et al. RADIAL VELOCITY MONITORING OFHEARTBEAT STARS, The Astrophysical Journal (2016). DOI: 10.3847/0004-637X/829/1/34

Susan E. Thompson et al. A CLASS OF ECCENTRIC BINARIES WITH DYNAMIC TIDAL DISTORTIONS DISCOVERED WITH, The Astrophysical Journal (2012). DOI: 10.1088/0004-637X/753/1/86

William F. Welsh et al. KOI-54: THEDISCOVERY OF TIDALLY EXCITED PULSATIONS AND BRIGHTENINGS IN A HIGHLY ECCENTRIC BINARY, The Astrophysical Journal Supplement Series (2011). DOI: 10.1088/0067-0049/197/1/4

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17 comments

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Ultron
1 / 5 (1) Oct 24, 2016
Nice, confirms my theory. There is actually no third star, the elliptical orbit is caused by high speed rotation of one or both stars, when its aligned.
antialias_physorg
5 / 5 (8) Oct 24, 2016
Nice, confirms my theory.

What theory? Published reference or it didn't happen.
Chris_Reeve
Oct 24, 2016
This comment has been removed by a moderator.
Captain Stumpy
4.4 / 5 (7) Oct 24, 2016
Since when do tidal forces cause ringing?
@illiterate chris/hannes
1- you forgot to add the context
—in other words, the diameters of the stars rapidly fluctuate as they orbit each other
2- you do realise that the "sound" that you hear isn't anything other than a "mechanical wave of pressure and displacement, through a medium such as air or water", right? (actually: gases, liquids, and solids)

technically, that means that rapidly fluctuating stars that would create a mechanical wave of pressure in a medium would technically be the same thing as "ringing" (or, since you only read pseudoscience eu bullsh*t, this means an "Oscillation in pressure, stress, particle displacement, particle velocity, etc., propagated in a medium with internal forces (e.g., elastic or viscous), or the superposition of such propagated oscillation" - see ANSI/ASA S1.1-2013 )
HannesAlfven
1 / 5 (5) Oct 24, 2016
Is the claim being made that the oscillations occur at a significantly higher frequency than the orbits themselves?
Captain Stumpy
5 / 5 (5) Oct 24, 2016
Is the claim being made that the oscillations occur at a significantly higher frequency than the orbits themselves?
@illiterate chris/hannes
Hmm...

if only there was a way to click on a hyperlink and open the articles, studies or other information and actually read what is written ...

satirical sarcastic hyperbole intended - i know full well you can't read actual science as that would violate your standing in the cult
Whydening Gyre
5 / 5 (6) Oct 24, 2016
Is the claim being made that the oscillations occur at a significantly higher frequency than the orbits themselves?

Are you talking about the "ringing"? Then, yes. It's the rotation. As to the actual frequency? Well below audible range, I'm sure...
"Ringing" was used more as metaphor/analogy.
But, then - I think you knew that..
Ultron
1 / 5 (2) Oct 25, 2016
Nice, confirms my theory.

What theory? Published reference or it didn't happen.


@antialias
Sure it is published. You can download it safely here:
http://vixra.org/abs/1609.0356

But is has 13 pages and it is very different compared to mainstream therefore it is quite complicated for understanding. Combined with your prejudice I guess you will not be willing to read it and able to understand it. But it predicts additional "gravitational attraction" around objects with speed rotation. Which would also mean that if these heartbeat stars would have speed rotation, it would explain the missing of tidal locking effect and creation of elliptical orbits. Because when the orbit is aligned with rotation of main star, it would add extra orbital energy during closest encounter and create and maintain the elliptical orbit.
antialias_physorg
4.4 / 5 (7) Oct 25, 2016
OK.. I spend one second on this paper.

references: wikipedia

Just three words on this: ...oh...my....god
For those who don't know: wikipedia is not an admissible reference in publications because wikipedia pages can be changed after the fact. Very selected fields allow references to static wikipedia archive pages (e.g. papers in computer sciences where hardcover books are mostly outdated by the time they are published). But for anything else these are a sure fire sign of utter crankery.

Then I spent some seconds on the images. They fly in the face of any and all conservation laws.

Yep...as suspected: garbage.
Ultron
5 / 5 (1) Oct 25, 2016
OK.. I spend one second on this paper.

references: wikipedia

Just three words on this: ...oh...my....god
For those who don't know: wikipedia is not an admissible reference in publications because wikipedia pages can be changed after the fact. Very selected fields allow references to static wikipedia archive pages (e.g. papers in computer sciences where hardcover books are mostly outdated by the time they are published). But for anything else these are a sure fire sign of utter crankery.

Then I spent some seconds on the images. They fly in the face of any and all conservation laws.

Yep...as suspected: garbage.


It is line with conservation laws. Surely it is an unusual interpretation, but there is no energy from nothing or disappearing into nothing.
Captain Stumpy
4 / 5 (4) Oct 25, 2016
OK.. I spend one second on this paper
@AA_P
i noticed the "vixra" link and didn't even bother to open it considering they admit the following
but as time has gone by it has become clear that Cornell has no plans to bow to pressure and change their policies
and
It is inevitable that viXra will therefore contain e-prints that many scientists will consider clearly wrong and unscientific
becuase
anybody who considers themselves to have done scientific work should have the right to place it in an archive in order to communicate the idea to a wide public
IOW - pseudoscience is OK by them
Ultron
2.3 / 5 (3) Oct 25, 2016
OK.. I spend one second on this paper
@AA_P
i noticed the "vixra" link and didn't even bother to open it considering they admit the following
but as time has gone by it has become clear that Cornell has no plans to bow to pressure and change their policies
and
It is inevitable that viXra will therefore contain e-prints that many scientists will consider clearly wrong and unscientific
becuase
anybody who considers themselves to have done scientific work should have the right to place it in an archive in order to communicate the idea to a wide public
IOW - pseudoscience is OK by them


Its perfectly OK if you choose to spend your time only on papers published in arxiv or in peer reviewed journals, but what I have seen, actually every physics paper is beyond your intellectual abilities and physics knowledge, so you dont need to bother to read my paper because you have not a chance to understand it :)
Captain Stumpy
4 / 5 (4) Oct 25, 2016
but what I have seen, actually every physics paper is beyond your intellectual abilities and physics knowledge
@ulTROLL
how would you know?
it's not like you've demonstrated even a cursory physics knowledge, so you are simply trolling with that comment (or intentional baiting)
so you dont need to bother to read my paper because you have not a chance to understand it
actually, i have read "your" papers... and they're bullsh*t
they don't pass peer reveiw for several reasons:
1- they don't have the requisite evidence

2- they violate known laws of physics

3- they violate known validated physics and other known validated studies

4- your references include other pseudoscience, which by definition means you're basing your ASSumptions on pseudoscience

so the reason you're not in a peer-reviewed journal isn't because of your different perspective
it's because your pseudoscience isn't science
Ultron
3 / 5 (2) Oct 25, 2016
@ulTROLL
how would you know?
it's not like you've demonstrated even a cursory physics knowledge, so you are simply trolling with that comment (or intentional baiting)
so you dont need to bother to read my paper because you have not a chance to understand it
actually, i have read "your" papers... and they're bullsh*t
they don't pass peer reveiw for several reasons:
1- they don't have the requisite evidence

2- they violate known laws of physics

3- they violate known validated physics and other known validated studies

4- your references include other pseudoscience, which by definition means you're basing your ASSumptions on pseudoscience

so the reason you're not in a peer-reviewed journal isn't because of your different perspective
it's because your pseudoscience isn't science


Experiments will decide who is the troll and who is right. It will take some time, but you will see.
Captain Stumpy
4 / 5 (4) Oct 25, 2016
Experiments will decide who is the troll and who is right
ulTROLL
correct
so long as the experiments are done correctly and there is evidence for correlation among other things
case in point: http://tylervigen...?id=1597

but you will see
the point is - until you have evidence, you're making a point based on faith

more importantly, a singular study is simply a point of interest
if you want fact or some kind of scientific truth, you need validation

what you're posting in your "study" on vixra is called, at best, and untested claim
however, considering the content, it is actually considered a false claim
See definitions here: http://www.auburn...ion.html

science has a methodology for a reason - to eliminate bias and pseudoscience like vixra
Ultron
2.3 / 5 (3) Oct 25, 2016
Experiments will decide who is the troll and who is right
ulTROLL
correct
so long as the experiments are done correctly and there is evidence for correlation among other things
case in point: http://tylervigen...?id=1597

science has a methodology for a reason - to eliminate bias and pseudoscience like vixra


If you would read it and understand it, you could see, that it accurately predicts which planets or asteroids should have rings and which should not have rings. Its quite weak evidence, but it is only a start. I will produce next version with additional specific predictions and with some luck, I will have an easy low budget experiment, which can be reproduced by anybody. Blueprint and material is ready and I will conduct it within few months. It doesnt really matter where is it published then, if the experiment will confirm it is done, then its only a matter of time.
Captain Stumpy
5 / 5 (4) Oct 26, 2016
If you would read it and understand it, you could see, that it accurately predicts which planets or asteroids should have rings and which should not have rings
@ulTROLL
really?
so then why isn't it in a peer-reviewed journal... and why are you using a vixra link?

please, by all means tell us all the details behind that one

include all those rejection letters you have that define "why" it wasn't published... i am willing to bet large sums of money that the rejection letters are pretty much summed up by my last post

care to compare by posting them publicly?

[crickets]

yeah... i thought not
It doesnt really matter where is it published then
ah, so you're not even in the published stage?
but yet you want me to accept the vixra publication sans evidence?

really?

and you can't see the problem with that?

and you wonder why i say that pseudoscience nut-jobs like you are more religious nutjobs than science?

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