Proxima Centauri - Our Solar System's Nearest Neighbor to Be Closely Examined for Exoplanets

While a star's planets are likely to orbit in a plane similar to that of its equator, I'm not aware of any effect that would make other, distant stars and planets assume the same planar alignment.
The chance of a transit survey finding planets is given as about 10 percent. This seem to suggest that the plane of various solar systems is expected to be randomly distributed.
Since the inclination of a planetary system could vary from 0 to 90 degrees, a transiting planet seems to need to be within about 4 & 1/2 degrees of our line of sight in order to eclipse its star.
Alpha Centauri A and B orbit one another in a plane inclined about 79 degrees from our line of sight. As Proxima is gravitationally bound to these other two stars, it may orbit in the same plane. Any planets it might have may orbit in this plane, too. If so, it appears that the transit method will not reveal them.

revisiting this thread because there has been at least one instrument that had a preliminary detection of a planet at Proxima. it is old news but i just ran across it now and the topic had come up again elsewhere. this is what happens when the search feature cannot find the thread you are looking for.

Hubble made a preliminary finding of a planet at .5 AU orbiting Proxima. Other instruments have so far failed to replicate the observation. Thus the observation remains unconfirmed, -to me that is not the same as being refuted or debunked.

en.wikipedia.org...

In 1998, an examination of Proxima Centauri using the Faint Object Spectrograph on board the Hubble Space Telescope appeared to show evidence of a companion orbiting at a distance of about 0.5 AU.[75] However, a subsequent search using the Wide Field Planetary Camera 2 failed to locate any companions.[21] Proxima Centauri, along with Alpha Centauri A and B, was among the "Tier 1" target stars for NASA's now-canceled Space Interferometry Mission (SIM), which would theoretically have been able to detect planets as small as three Earth-masses (M⊕) within two AU of a "Tier 1" target star.[23]

Note that except in unusual circumstances earth sized planets or smaller are below the threshold of detection for all instruments to date so for all we know there could be a gabillion of them orbiting such stars as Proxima, AC a AC b Barnards star, Wolf 359, Ross's star, Lelande and so on.

Proxima is the closest star to us and it is unlikely that there are any more true stars (even though red dwarfs are kind of hard to spot) lurking closer as yet undiscovered though "room temperature" Y type brown dwarfs are not out of the question entirely. Point being; Proxima is likely the first real star we will get to if the justification was there. Even if we decide that Alpha Centauri A or B are the true target of our first probes those probes would have to go by Proxima to get to them; so any such mission would probably include a flyby of Proxima anyway since it would be essentially a freeby for probes on that trajectory.

originally posted by: stormbringer1701
revisiting this thread because there has been at least one instrument that had a preliminary detection of a planet at Proxima. it is old news but i just ran across it now and the topic had come up again elsewhere. this is what happens when the search feature cannot find the thread you are looking for.

Hubble made a preliminary finding of a planet at .5 AU orbiting Proxima. Other instruments have so far failed to replicate the observation. Thus the observation remains unconfirmed, -to me that is not the same as being refuted or debunked.

en.wikipedia.org...

In 1998, an examination of Proxima Centauri using the Faint Object Spectrograph on board the Hubble Space Telescope appeared to show evidence of a companion orbiting at a distance of about 0.5 AU.[75] However, a subsequent search using the Wide Field Planetary Camera 2 failed to locate any companions.[21] Proxima Centauri, along with Alpha Centauri A and B, was among the "Tier 1" target stars for NASA's now-canceled Space Interferometry Mission (SIM), which would theoretically have been able to detect planets as small as three Earth-masses (M⊕) within two AU of a "Tier 1" target star.[23]

Note that except in unusual circumstances earth sized planets or smaller are below the threshold of detection for all instruments to date so for all we know there could be a gabillion of them orbiting such stars as Proxima, AC a AC b Barnards star, Wolf 359, Ross's star, Lelande and so on.

Proxima is the closest star to us and it is unlikely that there are any more true stars (even though red dwarfs are kind of hard to spot) lurking closer as yet undiscovered though "room temperature" Y type brown dwarfs are not out of the question entirely. Point being; Proxima is likely the first real star we will get to if the justification was there. Even if we decide that Alpha Centauri A or B are the true target of our first probes those probes would have to go by Proxima to get to them; so any such mission would probably include a flyby of Proxima anyway since it would be essentially a freeby for probes on that trajectory.

We shouldn't have too wait long for confirmation of a planet around Proxima or Alpha Centauri A or Alpha Centauri B. Between TESS (transits), E-ELT and TMT (radial velocity) and WFIRST and potentially Exo-S (direct imaging) we will be looking at these stars closely in the next 15 years. And that's just the NASA missions, ESA also has several exoplanet missions.

It's even possible that we get a positive detection through the ESPRESSO spectrograph at the VLT (Very Large Telescope at the European Souther Observatory in Chile.

It will be able to detect Earth sized planets around nearby stars by measuring radial velocity. With a radial velocity precision better than 10cm/s, an Earth mass planet in the habitable zone of a low mass star can be detected.

ESPRESSO will be installed at the VLT and go into operation next year

ATTENTION to planets hiding close to their parent stars: Gotcha suckers!

phys.org...

new technique allows stealthy planets to be seen. this means planets in the life zones will be easier to find. beta centarus b for example in the photographs in the article.

EDIT: to be clear Beta Centauri is not alpha centaurus B. instead it is about 350 light years away.


also the article does not give the lower mass limit for the new technique but instead says it works for planets smaller than jupiter. still at 350 LY i would hope that the lower bound is very much lower than that for stars within ten light years or so. one can hope. maybe JS can provide a realistic lower mass bound for such circumstances.

a reply to: JadeStar

(Image: Photo of Proxima Centauri from the Hubble Space Telescope)

Hubble sees PC as only one pixel, as it does all other supposed stars. The images that show more than one pixel are by way of some fancy formulas and a lot of number crunching. Astronomy, by definition, is a pseudoscience, and there is no proof that even the nearest stars to us are stars at all, and PC is most likely a planet, and any supposed planets around it may just be moons around a planet, not planets around a star.

originally posted by: stormbringer1701
ATTENTION to planets hiding close to their parent stars: Gotcha suckers!

phys.org...

new technique allows stealthy planets to be seen. this means planets in the life zones will be easier to find. beta centarus b for example in the photographs in the article.

EDIT: to be clear Beta Centauri is not alpha centaurus B. instead it is about 350 light years away.

also the article does not give the lower mass limit for the new technique but instead says it works for planets smaller than jupiter. still at 350 LY i would hope that the lower bound is very much lower than that for stars within ten light years or so. one can hope. maybe JS can provide a realistic lower mass bound for such circumstances.

Awesome!

I've been greatly following the the work to reduce the inner working angle of coronagraphs. This technique is very promising and possibly feasible to get down to tease out the Mini-Neptune/SuperEarth class of planets.

By the way it's not so much mass that is the issue in the case of direct imaging which they are using the coronagraph to do, it's the actual size of the planet being imaged that is metric to worry about.

originally posted by: GaryN
a reply to: JadeStar

(Image: Photo of Proxima Centauri from the Hubble Space Telescope)

Hubble sees PC as only one pixel, as it does all other supposed stars. The images that show more than one pixel are by way of some fancy formulas and a lot of number crunching.

Um this is wrong.

I think you listened to the lasted AstronomyCast and misunderstood part of what you heard. Those "fancy formulas and number crunching" vary in their "magicness" depending on which formulas and crunching is being employed. What you are talking about is when light falls on other pixels AROUND the one pixel on the CCD (in your example in reality star often take up more than one pixel as a point source, depending on the camera - Hubble has several different ones) but doesn't quite doesn't quite fill an entire adjacent pixel.

The evil unsharp mask is what I think you're thinking of.

That said, all CCDs extrapolate between pixels.

BTW: Betelgeuse easily fills plenty of pixels and has been resolved well beyond a point source with with Hubble:



And the European Southern Observatory's Very Large Telescope as well as with Keck and other large 'scopes.

And BTW while "pretty pictures' are of general interest, most of that light gathering is to be broken down in to learn different things through things like spectroscopy.

Astronomy, by definition, is a pseudoscience,

Because you don't understand it? Or because you said so?

and there is no proof that even the nearest stars to us are stars at all,

Now you're just talking crazy.

By that measure then according to you there was no proof that the moon wasn't made out of Green Cheese before we landed on it.

and PC is most likely a planet, and any supposed planets around it may just be moons around a planet, not planets around a star.

So Proxima Centuari is actually a planet with thermonuclear reactions which give it a temperature of over 3,000 Kelvin?! SERIOUSLY?!?!?

Do you know what a spectrograph is?

Because if you know how to use one and could prove your outrageous nons(ci)ence, you know with math and other fancy schmancy things you are averse to then step right up and collect your Nobel Prize.

I'd go more into the multitude of ways you are wrong but I'll leave that to stormbringer since this is his thread and I don't argue with crazy. It's a waste of time especially when crazy lacks the prerequisite basic astronomy technical knowledge.

No optics system is ever perfect but that does not make astronomy a "pseudoscience" LOL!!!

What you did yourself was actually learning one mostly true fact and then distorting it beyond belief to arrive at some real zany conclusions not at all rooted in observation.

cheese is too expensive for it to be that abundant. the prices are...Astronomical.

a reply to: JadeStar

BTW: Betelgeuse easily fills plenty of pixels and has been resolved well beyond a point source with with Hubble:

Betelgeuse is 5 pixels to Hubble, that image is a little more than 5 pixels. So how do they arrive at that image?

And what is Hubble seeing? Why is it the spectral lines are assumed to be from thermal excitation, when we know that there are lines from fluorescence? Just a small comet can have a coma millions of miles in diameter.
i.space.com...
Space.com says the coma is visible because of sunlight reflecting off the dust in the coma, but a test using a regular telescope, not Hubble, in space would see nothing. How can I prove it? Well, I need to be able to see images from a regular telescope in space, but there is no such animal. And according to just one criteria for a pseudoscience:
Lack of openness to testing by other experts
So lets have an expert on regular telescopes be allowed to place a telescope on the ISS, with DSLR camera attached, and looking out into space, not through Earths atmosphere, and see if we can get an image that looks like an image taken through the same telescope and camera from Earth. Won't happen, can't be done, so NASA will not even allow the experiment. Pseudoscience.

originally posted by: GaryN
a reply to: JadeStar

BTW: Betelgeuse easily fills plenty of pixels and has been resolved well beyond a point source with with Hubble:

Betelgeuse is 5 pixels to Hubble, that image is a little more than 5 pixels. So how do they arrive at that image?

And what is Hubble seeing? Why is it the spectral lines are assumed to be from thermal excitation, when we know that there are lines from fluorescence?

Because physics. We have a pretty good handle on how stars work.

But more specifically, even if we didn't, we'd know the difference between fluorescence and the spectral lines from a star burning hydrogen through thermonuclear fusion.

They are very clearly different from that of starlight.

You can go on believing astronomy is pseudoscience if you want but I'd encourage you to take an Astronomy 101 class and work up from there to get a better understanding of things because what I see you doing is pulling different scraps of things from here or there but placing them in entirely the wrong context and coming to some very wrong conclusions as a result.

Be forewarned though, unlike making up stories, math will be involved.

being our closest neighbor it should be examined by our young and old talented skywatchers

their young astronomers probably look at our system thru scopes just like the ones here on this planet