Ultrasmall Star System

[Wanderlust]

Kepler Object of Interest KOI-961 is a very small red dwarf.

This artist’s conception compares the KOI-961 planetary system to Jupiter and the largest four of its many moons. The KOI-961 planetary system hosts the three smallest planets known to orbit a star beyond our sun (called KOI-961.01, KOI-961.02 and KOI-961.03). The smallest of these planets, KOI-961.03, is about the same size as Mars. All three planets take less than two days to whip around their star.

The planets were discovered using data from NASA’s Kepler mission and ground-based telescopes. The KOI-961 star is a tiny “red dwarf,” just one-sixth the size of our sun. This planetary system is the most compact detected to date, with a scale closer to Jupiter and its moons than another star system.

The planet and moon orbits are drawn to the same scale. The sizes of the stars, planets and moons have been increased for visibility.

http://www.nasa.gov/mission_pages/kepler/news/smallest-exoplanets.html

 

[Amaris]

Neat!

 

[Kemaiku]

Damn that's small, I wonder what caused the formation of such a small system, and how.

 

[Wanderlust]

Damn that's small, I wonder what caused the formation of such a small system, and how.

Its prolly just scaled down because the Red Dwarf is small. Same formation technique just smaller. I bet the majority of systems are like this because of the mass abundance of Red Dwarfs.

These planets are certainly tidally locked, but if a sapience could terraform it and find a way to artificially spin it it would be a cozy system for worldbuilding operations.

 

[Ronald Held]

Small initial massed star tend to produce smaller planets. those planets migrated in from their formation location. Unvcertain if any giant planets were formed and migrated into the star. I do need to read a research grade paper to find out more.

 

[throwback]

I have noticed that many of the planets that we have discovered have orbits that take them very close to their stars. Do we have the resources and the technology to spot planets that lie further out in their solar systems?

 

[Wanderlust]

I have noticed that many of the planets that we have discovered have orbits that take them very close to their stars. Do we have the resources and the technology to spot planets that lie further out in their solar systems?

yes we do, just bigger planets are easier to detect

with Kepler we can detect anything at least the size of mars now, though its limited for nearby system surveys becasuee you have to stare at one spot for years. Kepler finding what its finding becasue its looking down the galactic spiral arm. its detected over 2,000 candidates that just happen to pass between us and the star, but there are billions of others in its field that are not detectable

 

[Kolrad]

I have noticed that many of the planets that we have discovered have orbits that take them very close to their stars. Do we have the resources and the technology to spot planets that lie further out in their solar systems?

I think the reason for this is that the farther out a planet is from its star, the longer it will take to complete an orbit. Jupiter takes 12 years to orbit the sun, Uranus takes over 80 years, and Pluto takes over 200 years, for instance.

At this point, almost all of the extrasolar planets we are discovering are invisible to us; we can only tell that a planet is there because its gravity causes the star to wobble back and forth as it orbits.

In order to be certain that you're seeing the effect of a planet, you probably need to watch it complete at least one orbit, and you can be more certain each time the pattern repeats. So the planets we've discovered so far have all been close to their stars, because they orbit quickly enough for astronomers to confirm the pattern.

I expect we'll hear of planets that are gradually farther and farther out.

 

[gastrof]

I think the reason for this is that the farther out a planet is from its star, the longer it will take to complete an orbit. Jupiter takes 12 years to orbit the sun, Uranus takes over 80 years, and Pluto takes over 200 years, for instance...

Pluto isn't a planet.

 

[ThankQ]

How much mass is needed to light the fuse of a star? While I know mass and size aren't necessarily related, that star just seems way to tiny. I recall something about several Jovian masses needed to kickstart fusion. Is my memory bad or are small red dwarfs dense little buggers?

 

[Wanderlust]

How much mass is needed to light the fuse of a star? While I know mass and size aren't necessarily related, that star just seems way to tiny. I recall something about several Jovian masses needed to kickstart fusion. Is my memory bad or are small red dwarfs dense little buggers?

70 Jupiters, stars are way more dense than jupiter

 

[Brandonv]

Looking at that picture, I find it interesting how close in size Jupiter is to the red dwarf star. It makes me wonder how close Jupiter is to being a star itself? How much more massive would it need to be for fusion to start?

 

[Flake]

Makes 2010 and Jupiter + Moons turning into a new star system all the more real and believable

 

[Ronald Held]

AFAIR 70 Jupiter masses only fuses Deuterium. For the standard P-P chain, it is approximately .08 solar masses.

 

[Wanderlust]

AFAIR 70 Jupiter masses only fuses Deuterium. For the standard P-P chain, it is approximately .08 solar masses.

Thats 13 jupiter masses.

.08 solar mass is 80 Jupiters.

 

[Ronald Held]

Time to look things up. minimum mass for deuterium fusion is approximately 13 Jupiter masses. 08 solar masses for p-p fusion(Kippenhan and Weigert, p268
)