Feeds

back to article NASA's Kepler telescope finds 5 new planets

NASA's Kepler space telescope has already uncovered new astronomical oddities and five large planets in its first six weeks of searching for Earth-like bodies outside our solar system. Although the quintet revealed by Kepler are all much larger than Earth and far too hot to harbor any life known to science, NASA said the …

COMMENTS

This topic is closed for new posts.
Gold badge
Thumb Up

so how do they get the density?

But 16.5 earth readii in diameter (If I'm reading this right) and the density of Sytrofoam?

Sounds more like a disk of something in orbit round a star. A *very* big disk

solar collector?

0
0
Go

Mini Dyson Sphere

Or a big Death Star orbiting a nearby forest moon.

Or a Styrofoam planet?

You decide.

0
0
Boffin

Assumptions

I'm guessing they are assuming spheres (which generally is not unreasonable) if we know the orbital period and the distance from the star then the mass is known, if we know the diameter then we know the density.

as for disks in space, I thought that giant dominos were de rigueur.

0
0

Great, but how far away?

Annoying thing about this article and the one on the NASA website is that it neglects to say how far away this solar system is from ours. Wonder why?

0
0
Boffin

Very uncertain, probably very distant

The patch of sky Kepler is looking at mostly contains stars which are a fair distance away (thousands of parsecs). Measuring the distances of stars that far away is difficult, the results usually have large error-bars. That's probably why the distances aren't mentioned - they're unknown to a precision worth quoting.

0
0
Gold badge
Joke

Easy one.

"Kepler 7b has about the same density as Styrofoam."

It's obviously new. I'm sure that whoever ordered it from Magrathea will get around to unpacking it soon and it'll become a perfectly normal, earth-type planet, briefly surrounded by huge chunks of styrofoam until the cleaners hoover up.

3
0
Silver badge
Thumb Up

They should ship them packed in bubble wrap

Because, you know, the new owners will then get the additional pleasure of popping all those bubbles. It'll also be a lot easier to clean up; just roll up the deflated sheets and tow them back for recycling.

0
0
Go

Box

It's probably a box of disks from HP.

0
0
Joke

going forward

"...but plan to analyze them going forward."

but what about planets with retrograde orbits?

1
0

Wow - good going guys and gals.

Stunning results already - hopefully they will be confirmed and Kepler will mirror Hubbles range of discoveries.

What with the LHC doing it's stuff well above spec. it's an interesting time to be following these.

I still want my flying car though.

ttfn

1
0
Silver badge
Thumb Up

Oh noes!

More planets, a few less gods!

Why it might turn out that religion is........err.......man made!

Oh the huge manitee !

0
0
Silver badge
Stop

Have they ruled out the possibility of a fault?

When they start measuring planets that are hotter than their host star or have an average density of less then that of expanded polystyrene, my immediate response would be to double check the instruments and the models they are using to calculate these values from the observations, as well as their assumptions about distance of host stars, etc.

0
0
Boffin

Simple and pretty secure

The way the density is derived is fairly simple, it's basic geometry and Newtonian physics. The major uncertainty comes from estimating the size and mass of the host star, and typically it's less than about 10% in each of those - certainly well enough understood to know that these exceptional planet densities are highly unlikely to be due to errors. Put it this way - if these estimates are way off then we seriously misunderstand how our Earth orbits our Sun!

0
0
Anonymous Coward

I'm assuming they do

But not knowing the exact methods they employ it makes me wonder too.

0
0
Silver badge
Boffin

However...

The parameters for our own solar system are fairly well known. For example, the size, distance from Earht and temperature of the Sun are known to a fairly decent precision.

When you start talking about distant objects, things like distance are calculated indirectly from such arcane things as red-shifts in the star's spectrum, which in turn tells us how fast it is moving from us, and from that, teh distance is estimated. Estimates of size are based upon brightness and distance, and models of how types of star other than our sun are supposed to work. Compound the errors in these various methods, and values become somewhat less determinate.

What I am suggesting is that if there is a flaw in any of the models used to calculate these things (for example a solar system is moving at a different speed to that expected for its distance, thus altering the red-shift), then the assumptions that have been made in the calculations of the star's distance, size and temperature are invalid.

0
0
Bronze badge
Flame

Cold Sun

We did a radio astronomy experiement when I was an undergraduate and concluded the (visible) surface of the Sun was 4 Kelvin! Our professor said this was a valuable result as it was within three orders of magnitude!

0
0
Paris Hilton

Huh?

"The size of planets can be estimated from measuring the size of the dip, and their temperatures by the type of star it orbits and the planet's orbital period."

How does temperature affect orbital period? Either this is a mistake or there's some really interesting and clever physics behind it. Either way, people should be told.

Paris because she knows all about bodies orbiting stars.

0
0
Boffin

Other way round

The orbital period (or more intuitively the distance from the star to the planet*) determines the planet temperature, not the other way round. Basically the closer they are to the star, the more energy they receive from it.

(*) orbital distance and orbital period are closely related through Keplers Laws.

0
0
Bronze badge
Stop

Orbital period

I think the assumption is that the temperature is a function of the orbital period given the further it is away from the host star then the colder it is.

0
0
Silver badge
Troll

If this is the case

Then can we assume that the planet with a higher temperature than its star is in a retrograde orbit, so they calculated its distance from the star as negative?

0
0
Paris Hilton

@twelvebore

Ah, that makes some sense. So the temperature is calculated, based on a steady state assumption, rather than measured. But that doesn't fit th statement below, which implies a measurement which doesn't match the theoretical calculation:

"For example, Kepler found celestial objects that are hotter than the host stars they orbit."

Paris because she knows all about hot bodies.

0
0

Life everywhere!

If we advance suffciently in technology to reach these planets easily, then likely we'll have the technology to move them into orbits that can support life. ...oh wait... ...the Lavamen have already been doing this in the universe for billions of years...

0
0

That's not Styrofoam!

It's MERINGUE!

0
0
Alien

Why look into space?

We already have 11 forms of aliens living under Dulce and Area51. If you believe whatever you read... Ask the US, but they wont admit it..... Welcome to our 'Draco' overlords ;)

Mines the one with the styrofoam firing flash gun in the pocket.

0
0
Silver badge
Boffin

"discoveries rolling off the assembly line"

Err, mixing your metaphors much, lads...?

1
0

Maybe...

"For example, Kepler found celestial objects that are hotter than the host stars they orbit."

Could it be a bunch of small stars orbiting a really heavy planet?

0
0
Silver badge
Coat

Mysterious superhot dwarfs?

Obviously planets on which someone switched on an LHC.

0
0
Silver badge
Dead Vulture

Okay El Reg, Fess Up!

Are you making up the stuff about the superhot mini? I can't find a mention of that one on the NASA website. Unfortunately I don't have access to the not-yet-peer-reviewed papers either...

0
0
Alien

Styrofoam planet = Dyson sphere?

Maybe the planet density is so low because it is hollow. Not really a Dyson sphere but not sure what to call it. So given the outside temperature how cool could the inside be kept?

0
0
This topic is closed for new posts.