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Insight and Generation Ships

The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' (I've found it!), but 'That's funny...' -Isaac Asimov.


ON this day

1954 – In Sylacauga, Alabama, USA, the Hodges meteorite crashes through a roof and hits a woman taking an afternoon nap; this is still the only documented case in the West of a human being hit by a meteorite.

20 Years ago!!

STS-27: Atlantis (December 2–6, 1988) William Shepherd first space mission which lasted 105 hours and carried Department of Defense payloads.

William would later go on to become part of the first crew of the ISS From October 31, 2000 to March 21, 2001, he and Russian cosmonauts Yuri Gidzenko and Sergey Krikalev served as Expedition 1,

Mission of the Week

Insight. The 8th time Nasa has successfully landed on Mars.

  • On podcast 62 back in January we announced that Insight was ready to Launch in 30-day launch window that opens on May 5th

  • By Podcast 80 Insight had Launched (with the universes first interplanetary Cubesats MARCO a and b) on 5 May 2018 at 11:05 UTC

  • As of this Podcast 109 At approximately 19:52:59 UTC[15] on 26 November 2018 the Insight Rover landed on Mars.

  • The Solar panels are deployed, a literal potential sticking point.

  • No other Space agency other than Nasa have achieved a successful landing on Mars and science mission on mars.

  • It is very difficult to land on Mars, Russia, China and ESA (schiaparelli) have never managed a 100% successful landing followed by actual science, The British came very close with Beale 2?

  • The Beagle 2 (named after Darwin’s Ship) was the British, Colin Pillinger, led Mars lander that was transported by the European Space Agency's 2003 Mars Express mission.

  • ESA declared the mission lost in February 2004, after numerous attempts to contact the spacecraft were made

  • The Beagle 2's fate remained a mystery until January 2015 (just after Colin’s death) when it was located intact on the surface of Mars in a series of images from NASA's Mars Reconnaissance Orbiter HiRISE camera. The images suggest that two of the spacecraft's four solar panels failed to deploy, blocking the spacecraft's communications antenna.

  • But Yes Nasa’s are the bomb with InSight joining Viking 1 & 2 landers, Mars Pathfinder; Mars Exploration Rovers Spirit & Opportunity, the Phoenix lander, and Curiosity rover.

  • Worth noting that in 1971 the Soviet Union sent probes Mars 2 and Mars 3 (Mars 1 blew up on take off) The Mars 2 and 3 probes each carried a lander, They were the first human artifacts to touchdown on Mars.

  • Mars 2 lander impacted on Mars only,

  • while Mars 3 Through aerodynamic braking, parachutes, and retro rockets, the lander achieved a soft landing and as a result was the first Martian soft lander and was able to transmit from the Martian surface during the first 20 seconds, the first data and a portion of the first picture. Which unfortunately is of nothing and the orientation is a bit odd. 47th Aniversary on sunday!!!

  • Nasa had a spate of bad luck and failures too, most horribly the Mars Climate Orbiter infamous for Lockheed Martin engineers mixing up the usage of English units with metric units, causing the orbiter to burn up while entering Mars' atmosphere...ouch.

  • Mars 2 and 3 also contained the first mini-Mars rovers, although they were completely broken on landing.

  • Back to InSight

  • The mission will determine if there is any seismic activity, measure the rate of heat flow from the interior, estimate the size of Mars' core and whether the core is liquid or solid.This data would be the first of its kind for Mars. It is also expected that frequent meteor air bursts can be used to gather more info

  • Using a seismometer called SEIS produced by the French space agency CNES (with help from many institutes including Imperial College), and a heat probe called HP3 produced by the German space agency DLR to study the planet's early geological evolution. HP3 is another German Mole like the one we talked about last week going to Enceladus.

  • Measurements Marsquakes, crust thickness, mantle viscosity, core radius and density, and other seismic activity should also bring a new deeper understanding of the other terrestrial planets—Mercury, Venus, Earth, Mars

  • Choosing a site for Insight to land at! Basically somewhere really quite boring as it’s not looking for surface features.

  • All roads lead to Elysium Planitia, so all 22 initial potential landing sites were located in this area

  • soft enough terrain to allow the heat flow probe to penetrate well into the ground.

  • flat, relatively rock-free to reduce the probability of complications during landing, and

  • A low elevation to allow for sufficient atmospheric braking during descent,

  • Near the equator to get enough sunlight for the solar panels all year round,

Mars is great subject in terms of the fundamental processes shaping planetary formation,

  • Mars may contains the most in-depth and accurate historical record,

  • It is big enough to have undergone the earliest accretion and internal heating processes that shaped our rocky planets,

  • small enough to have retained signs of those processes

  • a 2.4 m robotic arm that will be used to deploy the SEIS and HP3 instruments to Mars' surface.

  • There are two cameras, the IDC (Instrument Deployment camera) which is at the end of the arm.

  • The Instrument Context Camera (ICC) mounted below the lander's deck

  • Both with Colour 1024x1024 CCD chips

  • Oh by the way my name, boarding pass, is on Insight via a tiny little chip (along with about 2.4 million names on 2 chips, An electron beam etched letters only ​1⁄1000 the width of a human hair onto 8mm (0.3 in) silicon wafers.

Marco A and B, the first ever interplanetary cubesats!

  • The Mars Cube One (MarCO) spacecraft are a pair of 6U CubeSats that hitched a lift with InSight

  • To test CubeSat navigation and endurance in deep space

  • relay real-time communications during the probe's entry, descent and landing (EDL) phase, eight minute delay to get signal back to earth

  • The two 6U CubeSats, named MarCO A and B, measure 30 cm × 20 cm × 10 cm and flew as a pair for redundancy.

  • two CubeSats separated from the cruise stage after launch, and flew their own trajectory to Mars following insight and taking record breaking pictures too, .

  • They were not captured by Mars’ gravity well after their epic 53 million miles journey and will continue to orbit the sun. (crashing into Starman?)

  • The MArco sats were not needed for InSight’s mission success. But they definitely demonstrated of potential future capability.

  • During InSight's (EDL) it transmitted information at UHF radio band to NASA's Mars Reconnaissance Orbiter (MRO) which in turn forwards this telemetry to Earth using X band,

  • MRO can’t receive information over one band while transmitting on another. So JPL engineer would have to wait maybe up to an hour to hear news!!.

  • Enter MarCO's softball-size radio which provides both UHF (receive only) and X-band (receive and transmit) functions capable of immediately relaying information received over UHF.

  • The MarCO pair carried out their own communications and navigation experiments as they fly independently to the Red Planet. As well. They even took a picture of MArs once their job was over.

  • another nasa spacecraft OSIRISREx is now only about 60 km from Bennu, and will enter the 35 km Hill sphere of the asteroid on Dec 1


Hill Sphere

  • A Hill sphere approximates the gravitational sphere of influence of a smaller body in the face of perturbations from a more massive body.

  • So to be retained by a planet, a moon must have an orbit that lies within the planet's Hill sphere. But that moon would also have it’s own Hill sphere.. Any object within that distance would usually become a satellite of the moon, rather than of the planet itself

  • It was defined by the American astronomer George William Hill, based on the work of the French astronomer Édouard Roche. So is sometimes called the Roche sphere (not to be confused with the Roche limit, where the gravitational forces that hold a moon together are overcome by tidal forces, like Mars’ moons will at some point and be destroyed, perhaps becoming a ring around Mars, for a bit)

So with the earth the hill sphere lies within the L1 and L2 lagrange points, and of course the moon orbits well inside this. Anything outside this hill sphere would be perturbed by the sun and eventually go into orbit around the sun.

But the moon is slowly drifting away and just under 4 cm a year, so will fall outside the hill sphere at some point and leave us?

No, I don’t think so, the Moon is moving away from the Earth due to the tidal interaction between the Earth and the Moon, roughly speaking Moon’s gravity exerts a drag on the Earth that slows its rotation, and the Earth’s gravity exerts a pull on the Moon that expands its orbit, but eventually they will both be tidally locked ie, the earth will have been slowed to 47 day rotation and the moon 47 day orbit so both will face each other 50 billion years from now, and the moon will stop drifting away. But the Earth will be slowing down due to the sun, and then the Moon will start drifting inwards, perhaps eventually reaching the roche limit and becoming a ring system around the earth. But we said on our Sun episode Starting in about 5 billion years, the Sun will swell up into a red giant. At the peak of its expansion, it may swallow the Earth and the Moon. Yep, I doubt the earth will get it’s rings.

The Hill sphere is only an approximation, and other forces like Yarkovsky effect can eventually perturb an object out of the sphere. orbits at or just within the Hill sphere are not stable in the long term;Roughly speaking stable satellite orbits exist only inside 1/2 to 1/3 of the Hill radius.

Interesting fact, in LEO (low Earth orbit), a spherical body must be more dense than lead in order to fit inside its own Hill sphere, or else it will be incapable of supporting an orbit, so no an astronaut can’t orbit the ISS for example but A spherical geostationary satellite, however, could have orbiting bodies, even if it was reasonably non dense. (6% of water)

Even better HSF (Hill Sphere Fact)

What Body in the Solar system has the largest Hill Sphere???

Neptune!! Because it’s so far away from the sun ...jupiter comes 4th, and Eris ...yes Eris 5th!!

Answer me this ?

If you had some antimatter would it be repelled by gravity or like matter be attracted by it?

Basically the answer is probably attracted, but no-one knows for sure, so the Large Hadron Collider is going to find out with it’s Alpha and GBAR experiment, although they’re are racing against the 2 year closure coming up in the next few weeks. Any difference would be a huge breakthrough and point to the elusive quantum gravity, And if it turns up the very unlikely, but still possible answer of a complete reversal of gravity, then we may be able to finally do away with the god damn rocket equation. ...CAN YOU IMAGINE. So with that in mind we could build some proper starships, so let’s talk WORLDSHIPS!!!!


Worldship, or generation starship, a variation on the ship that is featured in Passengers!! is an interstellar ark starship that might take centuries to thousands of years to reach even nearby stars, the original occupants of a generation ship would grow old and die, leaving their descendants to continue traveling,

Robert H. Goddard, pioneer of rocket technology, was the first to write about very long duration interstellar journeys in his "The Last Migration" (1918) In this he described the death of the Sun and the necessity of an "interstellar ark". The crew would face the centuries of travel by sleeping and would be awakened when they reached another star system. Like in Passengers, but

Konstantin E. Tsiolkovsky, creator of the rocket equation, first described the need for multiple generations of passengers in his essay, "The Future of Earth and Mankind" (1928), a space colony equipped with engines that travels thousands of years which he called "Noah's Ark".

However the 1929 essay "The World, The Flesh, & The Devil" by J. D. Bernal is considered the first real description of a Generation ship

Bear in mind that Aeroplanes were really new, as was the rocket equation.

Gregory Matloff's concept is called a "colony ship" and Alan Bond called his concept a "world ship"

Basically this is a huge engineering challenge but surely a bigger social challenge?

So what are the main engineering problems and human problems that need to be sorted.

Well first of all Biosphere!! Creating a mini earth.

Imagine sending thousands of people into space and one system failing and them all dying, the systems in place would have to be amazing!! Has an experiment ever been done where 1000 of humans live for thousands of years in total isolation with no help or resources from a wider world?

We talked about Biosphere 2 previously on podcast and just how hard is is to do anything we have a long way to go when it comes to being self sustaining.

It looks like you would have to build a vast mini earth in reality.

Did you know that Stephen Bannon ran Bioshpere2 for a bit and the fired staff invaded tried to warn the crew they were in danger!!!

Human Biology and sustainable populations.

This has always fascinated me, how many people are required to maintain the human race, so that future generations are not too closely related and sibling like in genetics, the deadly gene etc. and the science on this is pretty undecided

The controversial 90’s Toba catastrophe theory, suggests 70,000 years ago human population was reduced to perhaps 1,000–10,000 breeding pairs when the Toba supervolcano in Indonesia erupted. Close call.

However, for a 200 year yourney anthropologist John Moore has estimated that a fairly normal population capacity of 160 people would allow normal family life (with the average individual having ten potential marriage partners), and no need for sperm banks, social engineering can reduce this estimate to 80 people.

But then in 2013 anthropologist Cameron Smith massively disagrees he created a new computer model to estimate a minimum reasonable population in the tens of thousands. Much larger than Moore's, as it takes the risk of accidents and disease into consideration, and assumes at least one bad catastrophe over the course of a 150-year journey.

So we’re not even close to definitely answering that one!

And sociology is even more controversial, it may even be immoral.

  • Generation ships travelling for long periods of time may see breakdowns in social structures. And of course mutiny

  • Robert A. Heinlein's Orphans of the Sky is a great exploration of this, everyone splits into tribes and the final destination is completely forgotten about and only the internal ships reality is important.

  • Concerns over the ethics of a project that locks the next generation into living an incarceration of which they had no say over, and that also ensures their options are extremely limited,

  • Aeon has a piece by Neil Levy deputy director of the Oxford Centre for Neuroethics on this that is worth a quick read. Of course, such questions arise for many of us, here and now. The differences between Earth and generation ships are differences in scale, not in kind, So studying generation ships really does give us a new way of looking at ethics here on earth ~(a generation ship itself)

  • For example the piece points out Children born on board generation ships might better off (with access to better medical care, better nutrition, education, and so on), than many born into poverty today. But they will still be locked into a project they did not choose.

  • It all depends on whether the goal – say, the survival of the species – is itself sufficiently valuable to justify it

  • Worldship Ethics is also dealt with in february’s edition of JBIS by the British interplanetary society

  • Yep there are loads of articles in JBIS about generation ships, some of them seminal from Alan Bond, Greg Matloff, Kelvin Long (who has organised conferences solely based on generation ships)

  • Several seminal papers on the topic were published in 1984 by Anthony Martin and Alan Bond. The biggest of the ‘dry’ World Ship concepts they developed had a diameter of 15-20 km, and was around 220 km in length. with cruise velocities of around 0.5% of the speed of light, taking hundreds of years to reach the nearest stars.

  • Radiation is a huge issue too. Deep space is much worse than anywhere on Earth's surface, or at the ISS, due to high-energy galactic cosmic rays (GCRs).

  • These mega high speed energetic particles can smash apart your DNA, increasing the risk of cancer, cataracts, neurological disorders, and a host of other medical disorders

  • One known practical solution to this problem is surrounding the crewed parts of the ship with a thick enough shielding such as a thick layer of maintained ice as proposed in The Songs of Distant Earth, a science fiction novel by Arthur C. Clarke

Something we’ve talked about before is the Wait Equation, which has been discussed at length on the podcast before, but is worth metioning again as it’s so cool. If a generation ship is expected to reach its destination in 200 years, during that period a better ship may be later developed that can reach it in 50 years. Thus, the ultimate annoying arrival to find a bunch of people already there that had it loads easier, and you never got to be “Proxima’s Neil Armstrong”

There are some intersting variations of generation ship

The Mathusula ship, where people are programmed to stop aging and therfore the first genration survives the whole trip, taking away some of the ethical issues.

Or the sleeper ship, like in passengers, should really be called a tomb ship as essentially everyone is dead so it’s a loss less demanding than a Mathusula ship You might have to keep a generation crew though. You are even at risk form your own internal radiation as you body isn’t constantly repairing the damage so you get a lethal dose of the time period.

How about the Seed ship that just goes first and terrafoms, plants stuff and even carries the ability to grow humans and teach them?

And this can be combined with a data ship that just carries digitalcopies of everything including minds, these can even be beemed accross the galaxy as a laser. These can be as small as a model spaceship on your table.!!!

Great quote here from anthony martin about why we should study generation ships

"If the World Ship concept survives this scrutiny intact, even if modified in detail, then the fundamental questions raised by the possibility of interstellar travel and colonisation about the apparent absence of extraterrestrial intelligence in the Solar neighbourhood, about the future of mankind, and about its place in the Universe will become more demanding of an answer.”

Another thought is why to another world if you can actuyally build a world, with probably far less energy, complexity and material, surely we’ll see megastructures before we see World ships, there is SOOOO much room in the solar system.

I think that generation ships are a good thought experiment, but do you think they are ever going to be built? What do you think we’d love to know.

Is this the answer to the Fermi Paradox, is it just to horrible to get on a ship knowing that you and your next few generation children, grandchildren etc are going to die on the ship and even though many ships have left before yours you never heard back from anyof them and you certainly wouldn’t know if they got to the distination?

Other Space News


· André-Hubert Roussel has been appointed by the ArianeGroup Board of Directors as Chief Executive Officer, effective January 1, 2019, He replaces Alain Charmeau, founder of ArianeGroup, who will retire after a transition period. André-Hubert Roussel, a member of ArianeGroup board since July 2018, is currently Head of Operations at Airbus Defence and Space

This week we should see quite a bit of space launch action.

  • SpaceX block5 falcon 9 "dedicated rideshare" mission will deliver roughly 90 payloads with the SHERPA space tug dispenser. We mentioned this way back in episode 98

  • 2 days later will be a rather stressful launch of Oleg Kononenko and the rookies Anne McClain of nasa and canadian David Saint-Jacques on a Soyuz to the ISS. I notice Luca Parmitano is part of the backup crew.

  • Next day is a bonanza - SpaceX CRS 16 going alos to the ISS

  • Ariane 5 carrying the very delayed GSAT-11 after the loss of GSAT-6. It’s been to a fro India and Kourou.

  • 7th December Then right on next weeks poddy we have the mighty Delta IV heavy carrying a Sat called the KH-11 Kennan or Crystal, an enourmous $5 billion spy satellite bigger and better than the hubble space telescope but pointing downwards. The satellites are believed to use a 2.4 m diameter prime mirror, which would proved a theoretical ground resolution of 15 cm

Shout out to


Turn your phone into a Cosmic Ray detector!!!

The Cosmic Ray Extremely Distributed Observatory (CREDO) Project is testing one of the many theories of dark matter. Wimps. Weakly interacting massive particles. These super massive particles born in the early Universe, should decay into high energy photons and the as these hit the atmosphere they come down in a shower or cascade of low energy photons. But you need a detector the size of earth to detect them!!! Or maybe lots of mini detectors that cover the planet.

So everyone’s mobile phone is capable of detecting them, and when your phone is charging and the camera is covered the app is looking for the interactions with your ccd. this detection along with the time and date it occurred and were your smartphone was is sent to the CREDO servers. So the worlds mobile phones can become this detector.

Download Credo at or from google play

Space fact

At the nano-nano (one billionth times one billionth) scale:

The earth is as small as an atom.(100 thousand fit on the width of a thin human hair)

The solar system is too small to see..

The nearest star, Alpha Centauri, is one and a half inches away.

The brightest star, Sirius, is three inches away.

The stars in the Big Dipper range from two to four feet away.

The North Star, Polaris, is thirteen feet away.

The Milky Way, our galaxy, is half a mile wide and has 150 billion stars.

The nearest galaxy, Andromeda, is a mile wide and seventeen miles away.

The next nearest galaxies are six in a group named Sculptor, 60 miles away.

There are 50-100 billion galaxies within a distance of 3-4 times around the Earth.

Light from this far away has been traveling since the big bang.