bolddcex

Then, what do we have:

Rmax = 1.04E9 * Dr meters

So Rmax = 1.10E-7 * Dr light-years

So it would take a receiving dish of diameter 9,100 km to receive our TV broadcasts out to a distance of 1 light-year. To receive our full TV video and audio signal out to a distance of 1,000 light-years the receiving dish must have a diameter of 9.1 million km. This seems outlandish to us but it may very well be within the capabilities of an advanced extraterrestrial civilization.

If we consider only the audio portion of the signal then the bandwidth improves from 6.0 MHz to 10 kHz and the diameter of the dish needed to receive just the audio portion out to a distance of 1,000 light-years is 370,000 km.

Add a little directionality to the signal, say let the transmitting dish (upload to satellite) have a diameter of 10 meters with wavelength of 64 cm, then the diameter of the receiver needed shrinks to 7,500 km to pick up our TV audio out to 1,000 light-years, 750 km to pick up our TV audio out to 100 light-years, and 75 km to pick up our TV audio out to 10 light-years. Some of these receiver sizes might even be feasible for our civilization in the distant future. So yes, it is possible for an advanced ET to pick up our TV signals at great distances.

Not with the atmosphere getting in the way. RV precision is almost at the level of atmospheric distortion (if it’s not already there). The sooner we get Obama in office, the sooner we’ll be able to get the space missions going again, which, incidentally, have been put on hold because of all the money and resources being funneled away to satisfy Bush’s fetish of getting man on Mars.

This is a common misconception that our TV signals fade out to zero past some certain point. The distance at which the signal falls below background noise depends on the collecting area of the receiver.

The equation for a directional transmitter is:

factor1 = Tb + Tn / SQRT(tau-r * Br)

factor2 = k * Bt * SNR * factor1

factor3 = Pt / factor2

factor4 = pi * Dt * Dr / (4*lambda)

Rmax = factor4 * SQRT(factor3)

For an isotropic transmitter the equation is:

Rmax = (Dr / 4) * SQRT(factor3)

Tb = background noise temperature of sky (deg K)
Tn = noise temperature of receiver (deg K)
tau-r = integration time of receiver (sec)
Br = bandwidth of receiver (hertz)
k = Boltzmann’s constant = 1.381E-23 joule per deg K
Bt = bandwidth of transmitter (hertz)
SNR = signal to noise ratio (typically greater than 1)
Pt = transmitter power (watts)
pi = 3.14159…
Dt = diameter of transmitting parabolic dish (meters)
Dr = diameter of receiving parabolic dish (meters)
lambda = wavelength of the signal (meters)
Rmax = maximum distance over which trasmissions are detectable by the receiver (meters)

Let’s consider television signals. Let’s assume the transmission is UHF channel 14 which has a video carrier at 471.25 MHz. The brightness temperature of the sky at this frequency is quite high, about 30 deg K. If it’s an NTSC signal (United States standard) then Bt is about 6 MHz. Let’s let Br equal 6 MHz too and tau-r = 0.167 microseconds. Then SQRT(tau-r * Br) is 1.0.

Let’s assume a typical television station power of 50,000 watts and assume the worst case, that the signal is isotropic (spread out in all directions). We’ll assume that the signal to noise ratio equals 1.0. Let’s also assume that some kind of supercivilization is picking up the broadcast so the noise temperature of the receiver is almost to the cosmic background noise level of 2.7 deg K (let’s put it as 5 deg K).

Then, what do we have:

Rmax = 1.04E9 * Dr meters

To Be Continued…

http://arcbuilder.home.bresnan.net/PCLMaster.html

The problem with that is that the transit method is a whole lot better in detecting objects near the star than far away objects, and the closest a planet is to its star, the smaller its Hill sphere is and the less likely it is to have moons, especially big ones.

Yo, Phil, here’s a neat topic for a post, methinks.

The only way I can thing of to discover a moon in another solar system is to be lucky enough to catch a planet transiting its sun, and at that very moment a large moon transiting the planet.

Exceptionally unlikely but with satellites imaging hundreds of thousands of stars sooner or later it’ll happen.

Never be able to detect??

I don’t think so. When I was growing up, the prevailing wisdom was that we would not be able to detect planets orbiting other stars. The dim light of their reflection would be washed out by the intense glare of the star itself. Oh, and because of distance, we couldn’t actually go and take a closer look.

Well, not only have we found planets orbiting other stars, we’ve found a *lot* of them. And there are a whole *lot* more of them waiting to be discovered.

Most of the ones we have discovered are big and orbit close to the primary. Now we are starting to find smaller ones, and I figure it won’t be long before we start finding them further out from their parent stars.

Instead of planetary reflections beign completely washed out, we’ve started developing techniques to separate reflected light from the star’s light, and that’s telling us stuff about these exoplanet’s atmospheres.

I’ll dare venture that, if these planets have moons (and I’ll bet at least some of them do), it’s only a matter of time before we detect them.

The only question (for me anyway) is whether I will be around to see it, or whether I will have gone into a growth industry pushing up daisies.

The planetary classification effort I like the best isn’t even scientific: it’s science-fictional: The Planetary Classification List, spawned by the ArcBuilder’s guys.

With over 200 exoplanets being discovered to date something like the Harvard/Yerkes stellar spectral type classification must be developed for exoplanets. Probably as soon as a significant number of exoplanet spectra are measured it will be. I would like to propose the following classification system:

Class: R (rocky)
Description:
Crust composed primarily of silicate
Frozen water is an insignificant part of the crust
Well-defined surface no more than 500 km below cloud tops (if there is an atmosphere at all)

Subclass: R1 (airless, geologically dead)
Description:
Atmospheric pressure at surface less than 1.0E-6 atm
No substantial geological activity
Spectrum: No atmospheric spectral data
Examples: Mercury, Earth’s moon

Subclass: R2 (airless, geologically active)
Description:
Atmospheric pressure at surface less than 1.0E-6 atm
Active geological processes (e.g., volcanism, faulting)
Spectrum:
May detect elements emitted into space due to volcanism (e.g., sulfur dioxide)
Example: Jupiter’s moon Io

Subclass: R3 (runaway greenhouse effect)
Description:
Atmospheric pressure at surface greater than 30 atm
Temperature increase at surface due to greenhouse effect greater than 150 deg K
Spectrum: carbon dioxide, nitrogen
Example: Venus

Subclass: R4 (thin atmosphere)
Description:
Atmospheric pressure at surface less than 0.03 atm
Spectrum: carbon dioxide, nitrogen
Example: Mars

Subclass: R5 (frozen ocean)
Description: Atmospheric pressure at surface between 0.03 and 30 atm
Substantial amount of frozen water at the surface
Spectrum: nitrogen, water vapor, carbon dioxide
Example: Earth (600 – 800 million years ago)

Subclass: R6 (liquid water, no life)
Description: Atmospheric pressure at surface between 0.03 and 30 atm
Substantial amount of liquid water at the surface
Atmospheric constituents are in equilibrium
Spectrum: nitrogen, water vapor, carbon dioxide
Example: Earth (4.25 billion years ago)

Subclass: R7 (liquid water, life)
Description: Atmospheric pressure at surface between 0.03 and 30 atm
Substantial amount of liquid water at the surface
Atmospheric constituents are NOT in equilibrium
Spectrum: nitrogen, oxygen, water vapor, carbon dioxide
Example: Earth (now)

********************************************************

Class: I (icy)
Description:
Crust composed primarily of frozen water
Silicate is an insignificant part of the crust
Well-defined surface no more than 500 km below cloud tops (if there is an atmosphere at all)

Subclass: I1 (airless, no shallow subsurface liquid ocean)
Description:
Atmospheric pressure at surface less than 1.0E-6 atm
Subsurface liquid ocean at a depth of at least 100 km or no subsurface liquid ocean at all
Spectrum: No atmospheric spectral data
Examples: Jupiter’s moon Ganymede, Jupiter’s moon Callisto

Subclass: I2 (airless, shallow subsurface liquid ocean)
Description:
Atmospheric pressure at surface less than 1.0E-6 atm
Subsurface liquid ocean at a depth of less than 100 km
Spectrum: No atmospheric spectral data
Example: Jupiter’s moon Europa

Subclass: I3 (thin atmosphere)
Description:
Atmospheric pressure at surface less than 0.03 atm
Spectrum: nitrogen
Example: Neptune’s moon Triton

Subclass: I4 (thick atmosphere)
Description:
Atmospheric pressure at surface at least 0.03 atm
May have substantial liquid at the surface
Spectrum: nitrogen, methane
Example: Saturn’s moon Titan

********************************************************

Class: G (gaseous)
Description:
Atmosphere is the only thing visible from space
There is no well-defined surface within 500 km below the cloud tops

Subclass: G1 (small, cold gas giants)
Description:
Mass less than 50 Earth masses
Distance from star greater than SQRT(LUMINOSITY)
Spectrum: hydrogen, helium, methane, ammonia
Examples: Uranus, Neptune

Subclass: G2 (medium, cold gas giants)
Description:
Mass between 50 and 500 Earth masses
Distance from star greater than SQRT(LUMINOSITY)
Spectrum: hydrogen, helium, methane, ammonia
Examples: Jupiter, Saturn

Subclass: G3 (large, cold gas giants)
Description:
Mass between 500 and 4,000 Earth masses
Distance from star greater than SQRT(LUMINOSITY)
Spectrum: ?
Example: HD 168443b

Subclass: G4 (small, hot gas giants)
Description:
Mass less than 50 Earth masses
Distance from star less than SQRT(LUMINOSITY)
Spectrum: water vapor
Example: Gliese 436b

Subclass: G5 (medium, hot gas giants)
Description:
Mass between 50 and 500 Earth masses
Distance from star less than SQRT(LUMINOSITY)
Spectrum: water vapor
Example: HD 209458b

Subclass: G6 (large, hot gas giants)
Description:
Mass between 500 and 4,000 Earth masses
Distance from star less than SQRT(LUMINOSITY)
Spectrum: ?
Example: Tau Bootis Ab

The search criteria are as follows:
albedo: from 0.15 to 0.85
greenhouse temperature increase: 0 to 100 degrees Celsius

****************************************

Star: Gliese 876
Luminosity: 0.0124 suns
Temperature: 3480 deg K
Mass: 0.32 solar masses
Spectral Type: M3.5V
Distance: 15.3 light-years

Planet: b
Semi-major axis: 0.208 A.U.
Eccentricity: 0.025
Periastrion: 0.203 A.U.
Apastrion: 0.213 A.U.
Orbital period: 60.94 days
Mass (Jupiters): greater than 1.935
Best fit: albedo = 0.15, greenhouse temp increase = 80 deg K
Habitable zone: 0.135 to 0.214 A.U.

****************************************

Star: Gliese 581
Luminosity: 0.013 suns
Temperature: 3480 deg K
Mass: 0.31 solar masses
Spectral Type: M3V
Distance: 20.4 light-years

Planet: b
Semi-major axis: 0.041 A.U.
Eccentricity: 0.02
Periastrion: 0.040 A.U.
Apastrion: 0.042 A.U.
Orbital period: 5.4 days
Mass (Jupiters): greater than 0.049
Best fit: albedo = 0.85, greenhouse temp increase = 30 deg K
Habitable zone: 0.0399 to 0.0580 A.U.

Planet: c
Semi-major axis: 0.073 A.U.
Eccentricity: 0.16
Periastrion: 0.061 A.U.
Apastrion: 0.085 A.U.
Orbital period: 12.9 days
Mass (Jupiters): greater than 0.016
Best fit: albedo = 0.70, greenhouse temp increase = 40 deg K
Habitable zone: 0.0604 to 0.0892 A.U.

****************************************

Star: 55 Cancri A
Luminosity: 0.63 suns
Temperature: 5250 deg K
Mass: 0.95 solar masses
Spectral Type: G8V
Distance: 40.9 light-years

Planet: f
Semi-major axis: 0.781 A.U.
Eccentricity: 0.2
Periastrion: 0.625 A.U.
Apastrion: 0.937 A.U.
Orbital period: 260 days
Mass (Jupiters): greater than 0.144
Best fit: albedo = 0.46, greenhouse temp increase = 54 deg K
Habitable zone: 0.625 to 0.942 A.U.

****************************************

Star: 47 Ursae Majoris
Luminosity: 1.54 suns
Temperature: 5740 deg K
Mass: 1.03 solar masses
Spectral Type: G1V
Distance: 45.9 light-years

Planet: b
Semi-major axis: 2.11 A.U.
Eccentricity: 0.049
Periastrion: 2.01 A.U.
Apastrion: 2.21 A.U.
Orbital period: 1083 days
Mass (Jupiters): greater than 2.60
Best fit: albedo = 0.15, greenhouse temp increase = 73 deg K
Habitable zone: 1.42 to 2.22 A.U.

****************************************

Star: Mu Arae
Luminosity: 1.75 suns
Temperature: 5813 deg K
Mass: 1.10 solar masses
Spectral Type: G3V
Distance: 49.8 light-years

Planet: b
Semi-major axis: 1.497 A.U.
Eccentricity: 0.128
Periastrion: 1.31 A.U.
Apastrion: 1.69 A.U.
Orbital period: 643.3 days
Mass (Jupiters): greater than 1.68
Best fit: albedo = 0.19, greenhouse temp increase = 40 deg K
Habitable zone: 1.15 to 1.70 A.U.

Planet: e
Semi-major axis: 0.921 A.U.
Eccentricity: 0.067
Periastrion: 0.859 A.U.
Apastrion: 0.983 A.U.
Orbital period: 310.6 days
Mass (Jupiters): greater than 0.5219
Best fit: albedo = 0.55, greenhouse temp increase = 40 deg K
Habitable zone: 0.859 to 1.27 A.U.

****************************************

Star: Iota Horologii
Luminosity: 1.8 suns
Temperature: 6125 deg K
Mass: 1.25 solar masses
Spectral Type: G0V
Distance: 50.6 light-years

Planet: b
Semi-major axis: 0.91 A.U.
Eccentricity: 0.22
Periastrion: 0.71 A.U.
Apastrion: 1.11 A.U.
Orbital period: 311.3 days
Mass (Jupiters): greater than 2.24
Best fit: albedo = 0.83, greenhouse temp increase = 77 deg K
Habitable zone: 0.709 to 1.12 A.U.

Bummer.”

This is a common misconception that our TV signals fade out to zero past some certain point. The distance at which the signal falls below background noise depends on the collecting area of the receiver. Thus, a more advanced extraterrestrial civilization can receive our TV signals and planetary radar signals out to a much greater distance than a relatively unadvanced civilization. I don’t have the equation in front of me but a really advanced civilization, say Kardashev Type II, might build a collecting area of millions of square kilometers. If so they could probably hear us from thousands of light-years away.

I’m thinking it was on http://www.xkcd.com.

Regardless, wonderful post, as always, BA.

___________________________

# StevoRon 17 Jun 2008 at 3:58 am

… & its done it once again (& again!) in the attempted correction. (Which also nearly fell foul of the spam filetr thingammy ..) Sigh.

Sorry.

BTW. Lets not forget we’ve now got quite a number of interesting low-mass systems with this trio of SuperVenus-cross-Neptunes, the trio of mini-Hot Neptune’s around HD 69830 & Gliese 581’s three low-mass SuperVenus x Neptunean planets.

I’d imagine these planets are :

- Molten or semi-molten rocks

- under deep layers of exotic hot high-pressure forms of ice;

- perhaps beneath deep oceans of pressurised chemicals

- and then smothered in thick atmospheres.

I’d expect them to be tidally locked; perhaps with one super hot hemisphere and another super cold one. Or perhaps the heat-flow is distributed by their atmospheres makin the whole planet hellishly similar temperature-wise a la Venus ..

But that’s my speculation on what these worlds may be & I’m hunble enough to admit we simply don’t know.

Earth-like? Not at all likely no.

Intriguing and worth thinking about? Definitely!

Sorry.

BTW. Lets not forget we’ve now got quite afew intresting low-mass systems with this tro of SuperVenus-cross- Neptunes, the trio of mini-Hot Neptune’s around HD 69830 & Gliese 581′s three low-mass SuperVenus x Neptunean planets.

I’d imagine all these planets are molten or semi-molten rocks under deep layers of exotic hot high-pressure forms of ice perhaps beneath deep ocena sof pressurised chemicals and then smothered in thick atmospheres. I’d expect them to be tidally locked and perhaps with one super hot hemisphere and one super cold one -or perhaps the heat-flow is distributred by atmospheric winds makes the whole planet hellishly similar temperature-wise a la Venus .. But that’s my speculation on what these worlds may be & I’m hunble enough to admit we simply don’t know.

Earth-like? Not at all likely no.
Intriguing and worth thinking about? Definitely!
_____________________________

* Gliese 581 : Gliese 581c orbits near the stars habitable zone in 13 days, could be rocky and is among lowest mass exoplanets yet found – 5 earth masses. The star also has a 15 earth-mass Hot Neptune orbiting in 5 days & an outer 8 earth-mass exoplanet orbiting in 84 days. Despite considerable initial hype, later studies suggest Gliese 581c is more likely to be a hostile Neptune-Venus cross than anything resembling an “earth-like” habitable planet.

- From http://www.astro.uiuc.edu/~kaler/sow/alkalurops.html

via

http://www.astro.uiuc.edu/~kaler/sow/class.html

(stars sorted by spectral class) :

â??Hotter stars fuse hydrogen to helium through the carbon cycle (in which carbon is used as a nuclear catalyst) rather than directly, have no circulating convective outer layers, and also tend to rotate much faster (Alkalurops [Mu Bootis -ed.] spinning at least 40 times faster than the Sun). â??

& from :

http://www.astro.uiuc.edu/~kaler/sow/anwar.html

on the star named (I kid you not) ANWAR AL FARKADAIN (Eta Ursae Minoris) :

â??… Lower-mass solar type stars rotate slowly (the sun taking 25 days at an equatorial speed of 2 kilometers per second), while high-mass stars rotate quickly. The division in rotation is rather sharp, the “rotation break” falling in the middle of class F. Anwar, rotating at least 76 kilometers per second (with a period under 1.4 days), falls just above the limit. Like the Sun, however, the rotation (and convection in its outer layers) give Anwar an X-ray-emitting hot corona. ”

MaDeR on 16 Jun 2008 at 1:03 pm :

Josephine, I think that planets are around most of stars. In other words, special conditions are required to NOT having planets (like being close to star of type O).

Actually, some of the most supermassive stars have had protoplanetary disks found around them notably two stars in the Large Magellanic Cloud had proto-planetarydisks discovered by the Spitzer telescope :

“These stars are so large that if they replaced our Sun in the centre of the solar system they would swallow whole Mercury, Venus, Earth and Mars.”

Source : Page 19, April 2006 issue of ‘Astronomy Now’ – News Update : “Super-Sized Solar Systems by Kulvinder Singh Chadha.

The accompanying illustration (a superb one which I’ve colour photocopied & used in talks!) showed a blue or white supergiant and planet-forming disk compared with our inner solar system. Such superlarge stars esp. if NOT redor yellow supergianst must be extremely massive stars with at least 10 and probably mor elike 20-120 solarmasses – putting their mass in the O-type dwarf and even hypergiant (Eg. P Cygni, Eta Carinae) range!

So it looks from that news like planetary formation runs from the largest to smallest of scale sand thatall spectral classes may be accompanied by planets …

Mind you, finding planets around such stars would be exceedingly difficult given such stars mind-boggling brightness and their high mass means it’ll be incredibly hard to detect any ‘wobble’ because their planets simply won’t have the comparative heft that Jovians or SuperJovians do against tugging smaller stars about …

PS. Sorry Torbjörn Larsson, OM the computer seems to have stuffed up your name – I cut & pasted so it should’ve turned out alright .. but then the wretched machine also messed me about with apostrophes / quotes so .. argh! Anyway #@%^^!!^^*&&$% computers!

…. SNIP ….. Btw, speaking to Josephineâ??s question, the same article claims that rotational velocity drops â??abruptlyâ?? in the 90 % or so stars lower than F2 category, which could indicate planetary disks to share momentum with. I dunno if there are other mechanisms proposed. (But IIRC it was hard going for the disk hypothesis here, some electromagnetic coupling is involved to explain a difficult scenario, so what else could it be?)

There are stars above this ‘rotation break’ which comes into play around mid spectral class F with protoplanetary disks (& evolved stars over this mass which started life as hot main-sequence A dwarfs but are now orange or red giants or sub-giants with planets – notably Pollux, Errai (Gamma Cepehi), Ain (Epsilon Tauri), Edasich (Iota Draconis) & HD 17092 b – the Jovian-type planet orbiting its orange giant star in 360 days which generated media interest for having an â??earth-likeâ?? orbit.

For examples, Vega (spectral class A0 V & so nearly a B-type dwarf), Fomalhaut (A3 V) and Beta Pictoris (A? V) all have protoplanetary disks that were detected back in the 1980′s and which were confirmed by later studies to be currently forming planets. Won’t swear to it but am pretty sure all those stars are (as is usual for spectral classes O,B,A & early F) rotating very rapidly.

For more info. I recomend checking out the stellar expert James B. Kaler’s website :

http://www.astro.uiuc.edu/~kaler/

and, for instance, seeing what he says with some F-type stars such as :

â??Asellus primusâ?? ?? Bootis F7 dwarf with M2 companion located 48 ly away. See : http://www.astro.uiuc.edu/~kaler/sow/asellusp.html

& Sigma Bootis 3 X L Sun, F2, K3 &M3 dwarf multiple with circumstellar dust disk al a Vega : http://www.astro.uiuc.edu/~kaler/sow/sigmaboo.html

****

From my Liszt of remarkable exoplanets :

* Gliese 436 b : The first known â??Hot Iceâ?? type planet, it was discovered by transiting to have a 50,000 km diameter â?? too small for a gas giant, too large for a superEarth. Models suggest it has a water-rich composition with a steamy atmosphere then a superheated ocean forced by high pressures at depths into exotic types of â??hot ice.â?? It orbits an M2 red dwarf star, 33 ly off in 2 and 1/2 days

* HD 69830 : Triple â??exo-Neptunesâ?? system around a Sun-like star 42 ly distant in Puppis. These planets all roughly Neptune-mass have 8, 31 and 197 day orbits with a large asteroid belt also being detected in the system.

* Pollux & â??Polydeucesâ?? : Orange giant Pollux is the only first magnitude and brightest star (ranks 17th in our sky by apparent magnitude) with a known exoplanet â?? a superjovian with a circular 590 d. orbit. This exoplanet dubbed “polydeuces” after a variant of the star’s name has triple Jupiter’s mass.

* Ain (Epsilon Tauri) belongs to the Hyades cluster forming the other â??bullâ??s eyeâ?? â?? the meaning of its name in Arabic opposite Aldebaran in the â??Vâ?? shape â?? and unlike Aldebaran it is a true member of the Hyades located 155 light years away. Ain b was the first exoplanet found in an open cluster and the most massive star yet found with a planet â??2.7 solar masses. Its superjovian planet has at least 7 and a half Jovian masses and orbits in 595 days 1.9 AU from its gargantuan star.

* Er Rai or Gamma Cephei b : Before “Polydeuces” was found around Pollux, this was previously the brightest star with an orbiting exoplanet. Errai is a 3rd mag. yellow sub-giant 45 ly off with a 1.5 Jove mass exoplanet in an orbit equivalent to just beyond Mars position in our system. Only three other named stars have confirmed exoplanets : Pollux, Ain (Epsilon Tauri) and Edasich (Iota Draconis), all the latter being orange giants. Ain belongs to the Hyades cluster forming the other â??bullâ??s eyeâ?? in the â??Vâ?? opposite Aldebaran.

* Edasich (Iota Draconis), a K2 type orange giant with a 9 Jupiter mass exoplanet in an elliptical 536-day orbit that ranges from 0.4 to 2 AU. Edasich is corrupted Arabic meaning â??male hyena.â?? Unfortunately, this star is a northern circumpolar one.

* HD 17092 b : Jovian-type planet orbiting its orange giant star in 360 days which generated media interest for having an â??earth-likeâ?? orbit. In reality, however, there is very little earth-like about it! For starters, the orbit is actually a bit further than Earthâ??s being about 1.3 AU given the greater (2.3 solar) mass of the star which consequently â??drivesâ?? the exoplanet along its orbit much faster. More importantly, this worldâ??s type of sun this is vastly different being a K0-type giant with a vastly greater diameter, surface area and luminosity. Calculations show this planets temperature would be around 500 degrees Celsius â?? hot enough to melt lead or zinc. Moreover, the exoplanet itself â??weighsâ?? over four Jupiter masses and is vastly different from being a rocky Earth-like planet! HD 17092 was the 10th orange or red giant star discovered to have planets orbiting it.

Like others have said, I think these three worlds around HD 40307 are more like “super-Venus” worlds than Super-Earth planets.

Well probably more like Neptune-Venus cross planets actually ..

They probably most likely look something like Gliese (GJ) 436 b the first known “Hot Ice” planet?

Still superluminous (ie. beyond merely brilliant) that we’ve found them and that we know of more than 300 exoplanets!

BBC reused tapes that contained early Doctor Who episodes and because of that some episodes are lost. The only copies left are traveling in the interstellar space. Unless some alien is copying them, the only way to retrieve them is to have a faster than light spaceship. Such spacecraft could break causality, and if that can be done, then also time traveling should be possible. Somehow sounds appropriate.

However, with telescopes coming with better resolution, we’ll be able to find planets in the habitable zones of stars.