B Transit of newly discovered exoplanet of Proxima centuri

  • B
  • Thread starter Thread starter jordankonisky
  • Start date Start date
  • Tags Tags
    exoplanet transit
AI Thread Summary
The newly discovered exoplanet Proxima Cen b orbits Proxima Centauri, and its size can potentially be determined by observing its transit across the star, although the likelihood of this occurring is only 1.5%. This low probability is due to the need for the planet's orbital plane to be nearly parallel to our line of sight, which is geometrically constrained by the sizes of the star and planet relative to their distance. Calculating the chance of a transit involves integrating over the entire sky, taking into account the star's radius and the planet's orbital radius. Future observations from the Extremely Large Telescope (E-ELT) in 2025 may provide clearer insights, while sending a probe at 10% of the speed of light could yield answers by 2060. The discussion highlights the challenges of observing distant exoplanets and the technological advancements needed for such missions.
jordankonisky
Messages
41
Reaction score
3
In descriptions of the newly discovered exoplanet, named Proxima Cen b, orbiting Proxima Centuri, it is mentioned that a determination of its size could be established by observing the planet’s transit in front of Proxima centuri, which would reveal the exoplanet’s diameter. It is my understanding that, to date, such projects have failed. I have also read that such projects are “expected” to fail, since geometrically speaking, there is only a 1.5% chance that Proxima Cen b passes across the face of Proxima. Why is is? And how is 1.5% calculated.
 
Astronomy news on Phys.org
The planet is far away from the star (compared to the stellar radius). Space is three-dimensional - the orbital plane has to be nearly parallel to our line of sight in order to have the planet in front of the star once per orbit. Where "nearly parallel" is the size of the star divided by the orbital radius of the planet: The closer the planet to the star, the less precise the alignment has to be.

If you do a proper integral over the whole sky, you can calculate that a fraction of (radius of star + radius of planet)/(orbital radius) of the sky can see a transit.
 
Than you so much for responding to my query and providing such a clear answer.
 
If we sent a probe that way at 10% of the speed of light, by about 2060 we'd have all the answers.
 
Or we wait until E-ELT takes a direct picture in ~2025. The maximal angular separation is 0.04 arcseconds, contrast should be something like 1 in a million. In the range of EPICS, which can resolve 1 in 1 million contrasts down to 0.033 arcseconds, or 0.04 arcsecond separation up to a contrast of 1 in 1 billion.
Source, page 2.
 
  • Like
Likes jim mcnamara
lifeonmercury said:
If we sent a probe that way at 10% of the speed of light, by about 2060 we'd have all the answers.

And if he had some ham we'd have ham and eggs, if we had some eggs.

This is 4000x faster than any space probe built.
 
This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...
Asteroid, Data - 1.2% risk of an impact on December 22, 2032. The estimated diameter is 55 m and an impact would likely release an energy of 8 megatons of TNT equivalent, although these numbers have a large uncertainty - it could also be 1 or 100 megatons. Currently the object has level 3 on the Torino scale, the second-highest ever (after Apophis) and only the third object to exceed level 1. Most likely it will miss, and if it hits then most likely it'll hit an ocean and be harmless, but...
Back
Top