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Starlight
- A better measurement that made the model worse
- A brightness is a distance only if something is known
- A continuum that was never observed
- A diameter that depends on a model atmosphere
- A field strength read off a line that will not split
- A luminosity class is a density measurement
- A magnitude has to say which light
- A magnitude in a band the source never had
- A magnitude measured where nothing was measured
- A mean dominated by the gaps
- A minimum that was mistaken for a principle
- An angle of five hundredths of an arcsecond
- An instrument more polarised than the sky
- A period found in the gaps
- A phase that survives what corrupts it
- A response measured pixel by pixel
- A sample brighter than the population it came from
- A scale that runs backwards, multiplies, and works
- A shift in a line is a speedometer, and it works at any distance
- A slope that needs no source
- A spectrum with no continuum left in it
- A spectrum with no temperature in it
- A speed read off an edge
- A temperature and a gravity that trade against each other
- A temperature that depends on where the observer stands
- A velocity that is an average of lines that disagree
- Colour is a thermometer, and it reads across the galaxy
- Composition, read from what is missing
- Dust makes everything look further away
- Every distance is measured with the last one
- How much of a line is not in its depth
- Resolution without a mirror
- The circulation that should have stirred every fast rotator
- The continuum is made by one atom in ten thousand
- The depth is not the area
- The direction a photon count throws away
- The distance is not one over the parallax
- The dust is not lost light, it is moved light
- The error bar that comes from counting
- The faint star is measured against a brighter sky
- The light that is missing from the edge
- The metre per second that is not the star
- The pole-on stars a brightness limit prefers
- The same star through two telescopes
- The same width for three different reasons
- The second thing a spectrum says
- The surface that is a depth
- The tallest peak in nothing at all
- The triangle that reaches the stars, and stops
- Two instruments blind in opposite directions
- Why hydrogen's lines are strongest where hydrogen is not
- The classical law gives every star one colour
- Three shifts larger than the error bar, and two that cancel
- Two laws that are one curve read twice
- The best aperture throws away a tenth
- The comparison stars are part of the measurement
- How much of the picture is the prior
- The position closure throws away
- A limb brighter than the middle
- A sight line stops at two thirds
- A source that rotates its own light
- A rate the wind has no choice about
- A temperature that is a speed
- Odds for a planet that depend on a guess about its size
- The fainter polarisation belongs to the lobe further away
- An angle too small to measure, read from a colour
- A wall built by a steep opacity
- A size read from the slope of a colour
- The photons on the sides of the lines
- A redshift that is wrong by three
- The lines a synthesis keeps pay for the ones it lacks
- A prior the survey measures through its own noise
- A glow that weighs the grains reddening cannot see
- A baseline that grows four astronomical units a year
- Two clocks for one lobe
- A wind that may be too hot to see
- Light that adds, corrected as if it multiplied
- A line darker than any temperature in the gas
- A width that knows how bright the star is
- A shared axis hides at the angle where it does no harm
- The cancellation that leaves with the hot stars
- Two distances that must agree if light is conserved
- A floor the star sets for itself
- A spot a slow star hides inside its velocity
- A lobe that reads the time since it was stirred
- A rotation measure the lobe writes on its own boundary
- A calibration chosen by the measurement it calibrates
- A polarisation measured faster than the air changes
- A profile that averages a decade of depth
- A temperature read against the light's long tail
- Where a shrinking star stops boiling at its centre
- A rotation found where the transform goes dark
- A periodogram shaped like a shadow
- A halo the telescope paints on every galaxy
- A hundred kelvin under every radius
- A mean that a few per cent of strays can drag
- A diameter smaller than the fringes can see
- A wavelength coincidence that weighs a neutron star
- A polarisation that a round star cancels
- An ionised sphere that is a count of photons
- An element that was only empty space
Galaxies
- A birth rate measured from light nothing young emitted
- A bridge and a tail drawn by one force
- A cloud that cannot become a star
- A cluster weighed three ways
- A count with a knee in it
- A direction measured by something with no strength in it
- A disc held open by what cannot be photographed
- A disc that turns slower than its mass requires
- A disc the size its halo was born with
- A dispersion inflated by orbits nobody resolved
- A flare that puts a ceiling on a mass
- A galaxy held up by disorder
- A galaxy measured from inside it
- A histogram that says the box was not closed
- A hole that says mass times time
- A line width that is a distance
- An argument about the innermost kiloparsec
- An arm that cannot be made of stars
- An arm that is undone by the work it does
- A one-per-cent distortion, and a million galaxies to see it
- A rotation curve that refuses to fall
- A sheet of mass that changes nothing but the answer
- A size measured from a delay
- A stream is not the orbit it came from
- One velocity and two distances
- Red, gas-poor, and still spiral-shaped
- Support that cannot be squeezed away
- The baryons that are not in the galaxies
- The brightness distance cannot touch
- The cloud that cannot hold itself up
- The debris that returns fastest lights up last
- The energy at which a sky begins to point
- The factor that multiplies every quasar mass
- The gas runs out before the galaxy does
- The last parsec, and the stars that are not there
- The line a star is swallowed at is not the horizon
- The mass at the centre that is not stars
- The mass that is not the light
- The same curve, two galaxies
- The speed a line width stands in for
- The stars a black hole eats come from a narrow band
- The support and the seed are the same motions
- Three mass models that fit the same curve
- Two colours, and almost nothing between
- Two geometries and one bit to choose between them
- Two parameters that lensing measures as one
- Two temperatures, and nothing in between
- Weighed by the light that bends past it
- Where a pattern is allowed to turn
- Whether it merges is a ratio of two times
- The count theory predicts, and the inference it costs
- Two counts that are not the same shape
- The same census, taken in two places
- The metals a galaxy keeps measure what it threw away
- A gradient the old stars have walked away from
- The iron clock has no single delay
- Two ways to stop that do not interact
- A crossing time that is the filter's
- Where the sky is the measurement
- A radius that is a measurement of the threshold
- The halo a galaxy drags inward
- A horizon drawn by light at three kelvin
- Two spins that cancel, and an orbit that leaves
- A delay that tells which way the gas is moving
- A spectrum that counts what no single gap can
- A foreground drawn by the field it traces
- A measurement of dark matter that needs a model of galaxies
- A collision decided by a speed across the sky
- Stars that weigh and do not shine
- One acceleration, and every galaxy's missing mass
- The bar leaves its gas where the orbits turn
- A black hole thrown out by its own merger
- The black holes that can be weighed are the heavy ones
- The one radius where the orbits stop mattering
- A history the rotation curve absorbs
- A cusp a black hole would sharpen
- One slope read twice, and the reading that disagrees
- A positron that cannot have come far
- An atomic ceiling set by the dust
- A temperature that belongs to none of the gas
- A dispersion that weighs the sheet only if the orbits are known
- A hundred lenses and one assumption
- A distance measured with a stopwatch
- Motions across the sky measure the orbits first
- One profile for a galaxy that has two
- A halo with too much slow gas for a disc
- A stirring supernovae cannot pay for
- The grains that glow and the grains that align
- A disc weighed by how far its stars climb
- A spiral drawn by velocities alone
- A galaxy born without a halo
- A lag too short for the light
- A stream that points the wrong way
- A falling polarisation and the angle that says why
- A molecule that forms too slowly to wait for
- A flare rate a hole cannot afford for long
- A lifetime read from how gas and stars sit apart
- A lens counted instead of measured
- A halo weighed by counting its oldest clusters
- A cooling flow that never arrives
- A galaxy that grows faster by eating small
Cosmology
- A blur that measures a depth
- A budget whose familiar part is five per cent
- A coincidence that is a factor of fourteen
- A constant that is an angle divided by a length
- A dipole a hundred times the signal
- A factor of three, and the flatness that prices every cure
- A forest with no continuum left
- A horizon three times larger than the age allows
- A length in centimetres, measured against an angle
- A map stretched by the thing it measures
- A map that is not of positions
- A mass measured by what it stopped from forming
- An abundance with no direction to correct in
- An amplitude and a depth that arrive multiplied
- An expansion that was supposed to be slowing
- An orbit feels the acceleration and never the rate
- A particle count taken from a dwarf galaxy
- A ratio that is an energy and a distance
- A redshift that changes while it is watched
- A residual that is somebody else's velocity
- A ruler measured along and across
- A shadow that does not get fainter with distance
- A standing wave frozen at one instant
- A test that can only fail one way
- A trough that proves the forest survived
- Four abundances and one free parameter
- Four distances to the same galaxy
- Half the ordinary matter was missing, and a millisecond found it
- Homogeneous above a hundred megaparsecs
- It ends when the walls meet
- One number that is an age, a size and a density
- Spin acquired before there was anything to spin
- The age of the universe weighs the Local Group
- The clock on which light travels in straight lines
- The epoch nobody saw moves the tilt
- The galaxies that are already out of reach
- The most perfect blackbody ever measured
- The number that would say whether it is a constant
- The residue that failed to burn
- The same ruler measured twice, ten billion years apart
- The seed that cannot be remembered
- The shift that is not a Doppler shift
- The Sun's speed counted in quasars comes out twice too large
- The surface the background actually is
- The tilt knows the slope and not the height
- The universe that was lumpy at one second
- Two coincidences with one mechanism
- Two horizons that differ only in who is inside
- Whether there is a horizon at all
- Why the sky is dark
- The darkness has a number in it
- A background weighed by what it stops
- Two skies where the paradox comes out right
- A velocity that has the colour of the sky
- Too few clusters, or a scale that reads light
- A null that moves with the temperature
- A blur undone with the field that made it
- A ruler read in absorption
- The shape a galaxy was given before it was lensed
- A spin that remembers the field and not its sign
- A shadow cast on the microwave background
- A field that would have moved the ruler
- An emptiness that expands faster
- The same constant, measured twice, five sigma apart
- A crossing that may belong to the fitting form
- The first three minutes use two lifetimes
- A lower limit made of three lengths and a missing echo
- A ruler shortened by something already gone
- A background that stops breaking into sources
- The histogram of a sky too crowded to count
- Velocities that see past the edge of the map
- A void is not short of dwarf haloes
- A flatness that needs a second distance
- Polarised only where the glow was lopsided
- A speed read from the finest spots in the map
- A void heated from the inside
- An edge that needs no pulsation
- An alignment a disc shows only when it is tipped
- A cluster weighed against the background behind it
- A map of galaxies none of which was seen
- A line from the wrong redshift lands at the wrong distance
- Every thawing field falls on one line
- The growth that tells a substance from a law
- A mass scale checked near and carried far
- A void dated by the dwarfs that lit in time
- An echo heard only from the weakest fields
- A conversion measured without an alignment
- A wave pulled ahead by particles that outran it
- A depth that belongs to the fit as much as the sky
- A dimming short by what young stars repay
- A hole too deep for the sky to have made
- A null that removes a model and not its family
- A bound below the floor is not a mass
- A field the galaxies cannot spread far enough
- A twist that decides where the field ends
- A ratio in which the galaxies cancel
- A drift in the tilt that is the tilt squared
- A flow too quiet for the lumps it runs between
- A clock that flickers without a tick
- A clump that waits for the radiation to thin
- A balance that is a saddle
Spaceflight
- A boom held upright by a difference in gravity
- A burn that moves the wrong way
- A coefficient that belongs to the surface, not the satellite
- A collision rate that needs no collision
- A density model wrong by a factor of two
- A manoeuvre that has never been flown once
- A map of the transfers that are free
- An angle measured against a quasar
- An ocean found in a Doppler residual
- An orbit that speeds up as it is slowed down
- A plane change paid at the worst speed there is
- A position measured from a frequency
- A rotation split between two burns
- A satellite that drifts to one of two longitudes
- A spin that left the axis it was given
- A stationary satellite that draws a figure of eight
- A swath is sized at the equator
- A tumble stopped by the field it tumbles through
- A weather forecast made out of orbits
- A wingnut that turns over on its own
- Catching up by slowing down, which cost Gemini 4 its fuel
- Five satellites and not four
- Flying further away in order to turn
- Four media between the antenna and the spacecraft
- Going too far in order to arrive cheaply
- One trajectory, stitched from three two-body problems
- Stealing speed from a planet, which does not notice
- The cheapest place to turn
- The cheapest way between two orbits, and why it is so slow
- The circle a station can see
- The discontinuity a patched conic hides
- The exponential that decides what can be flown
- The fragments nobody can see and cannot shield against
- The line under a satellite
- The orbit that has to be paid for every year
- The planet pays, and it shows
- The same burn is worth more when moving fast
- The same planet, three times
- The speed that does not come back, and the √2 that separates it
- The spin that has to be put somewhere
- The stage that has to be thrown away
- The transfer that costs more the gentler it is
- The window that comes back and the cost that does not
- Three clocks and nothing to fall onto
- Two dates decide a mission
- A corridor a degree and a half wide
- An equation that does not break at the speed of light
- Choosing a propellant is choosing a molecular weight
- Orbit costs 7.8 and a launch buys 9.4
- The split that is not an equal split
- The tube that leads out of a neck
- One square root that raises the orbit and turns it
- The engine is chosen by the calendar
- A drive with no rocket equation
- A fuel gauge that is worst when it is needed
- An unstable point that costs less to hold than a stable orbit
- The ratio that is not √2
- The speed that is left over
- The relative orbit that breathes
- A camera that cannot see how far
- A belt emptied over one ocean
- The cheapest circle to stop in
- A wall across the porkchop
- The first weeks off a Hohmann transfer are nearly free
- A millimetre a second at launch, seventy-six kilometres at Mars
- The gap between the belts is a race between two clocks
- Fifty objects that hold most of the future
- Braking on a moon before braking with the engine
- A graveyard height with a term for sunlight
- A peak that says where the electrons were made
- A grapple point that moves faster than the orbit
- The wall sells inclination at the dearest price
- A flyby that multiplies its own aiming error
- A plane change borrowed from the Moon
- The thrust that rounds an orbit turns once a revolution
- A trajectory with no good first guess
- A removal rate set by one percentage
- A burn that cannot happen at one point
- Two metres overhead and thirty at the horizon
- The one axis the field will not take
- A climb out of the ecliptic paid for in orbits
- A belt drained through its outer door
- A dropout that is only the field
- No single way to point a long burn
- A plane turned only where turning is cheap
- A thruster that must arrive slow
- An aim bought with the last day of the approach
- Four satellites in view, and which four
- A ring where nothing leaves and little shatters
- A turn spread where the climb leaves room
- A height the map already knows
- A rendezvous paid for in air
- An arrival the Sun hands over
- A booster that flies home pays with the stage above it
- A turn that costs more when the shadow sits on the node
- A dodge made of air
- An orbit lost to a burn that did not fire
- A tow with no rope
- A cable with a rocket equation of its own
- A way home that needs no engine
- A timetable that orbits the Sun
Sky
- A boundary that hardly moves
- A clock whose zero is moving
- A frame made of things that are not points
- A month that has to be tabulated
- An aurora that is a sixth root inside an arcsine
- An error budget added in quadrature
- An hour that stretched with the season
- A population counted by shadows that never repeat
- A right ascension is a date
- A second that depends on where the clock is
- A shape measured by the edge of a shadow
- A solar radius measured past a mountain range
- A star that blinked before it should have
- A Sun that stops and runs backwards
- A ten-metre mirror that resolves like a ten-centimetre one
- A tilt held still by being too fast to resonate
- A tilt that is not a constant
- A wobble that should have stopped
- A year that is not a whole number of days
- Each event pays for the prediction of the next
- Five numbers from one wiggle
- Four numbers that weigh a planet's core
- On Mars the orbit outweighs the tilt
- Ozone keeps the twilight zenith blue
- Phases are not shadows, and eclipses are
- Six kinds of second
- The air's height against the planet sets the twilight
- The atmosphere is a prism as well as a lens
- The brightest instant of an occultation is its middle
- The correction has to be faster than the air
- The day that is four minutes short
- The earliest sunset is not the shortest day
- The eclipse that repeats a third of a world away
- The edge of a shadow is a wave
- The face that is not quite fixed
- The flare that arrives from somewhere else
- The loop a planet does not make
- The other twenty arcseconds
- The pole star has a shelf life, and the sky has a slow hand
- The shadow that climbs the zenith
- The smallest term between a clock and the Sun
- The solar system measured from inside one orbit
- The sphere that is not there, and why it is still the right model
- The Sun is a bad clock, by up to sixteen minutes
- The Sun sets before it sets
- The Sun's path, and the tilt that makes the seasons
- The whole sky drifting towards one point
- The wobble inside the wobble
- Three definitions of night
- Two fictitious suns in sequence
- Where a star is depends on who is asking
- Five zones, and one angle
- The sunniest place is the summer pole
- The hottest month is not the sunniest
- A triangle of meetings that turns in eight centuries
- Brightest as a crescent, and not as a disc
- A right angle short by a seventh of a degree
- A rocking nobody started
- A square field imaged as a squashed one
- An atmosphere that bends light round the Earth
- The sky crowded forward by the observer's speed
- A time scale that is finished after it is used
- A substorm timed by webers and volts
- A season without a night
- A full moon computed from the year number
- A sharp image kept by throwing the rest away
- A past that can only be given as odds
- A core that wobbles at its own period
- A clock allowed to leave the Sun
- A clock made of neutron stars
- Luck that reaches as far as the quiet air
- A sunset's shape is a sounding of the air
- The night is late because the light bounces twice
- Every star in the catalogue is bent by the Sun
- The Sun is three hundred kilometres larger seen edge-on
- A month that begins when someone sees it
- A day longer than the year
- A storm weighed by a compass needle
- A planet that borrows the wind's field
- A frame fixed before its centre was found
- An eclipse held in place to a millimetre
- A clock whose best interval is three years
- Two clouds that shine alike until the crescent
- A twinkle that knows the high air and not the low
- Layers that keep the rhythm and lose the dates
- A state the Moon had to jump to
- A shield that depends on what limits the leak
- The shadow that also switches off the satellites
- A schedule written by where the Sun is
- A year that depends on the season counting it
- A polarisation capped by the light the planet catches
- A reflector built wrong so the light comes home
- A rhythm in the rock that measures the Moon
- A glow counted in square metres of sunlit metal
- Two exponents a solar cycle cannot pull apart
- A midplane that depends on how far it is averaged
- A Moon measured in banded iron
- A year kept by a star seen for one morning
- A Moon that rises further north than the Sun
- A full Moon that stops rising later
- A Moon lit by every sunset at once
Stars
- A brightness that would blow the star apart
- A clock read against a model of everything in between
- A clock that runs down and says what it is
- A clock that stops while its interior freezes
- A clock with no fuel in it
- A convective boundary with no theory to fix it
- A corner of the diagram that has to be earned
- A field that would have arrived ten thousand times too strong
- A floor under the centre that assumes nothing
- A fluid that turns as one piece
- A flux that is a thermometer to a tenth of a per cent
- A length nobody derived, fitted to one star
- A magnetic clock read off a butterfly
- A mass function corrected by an age
- An age read off a bend
- An equation of state is already a star
- A neutron star born turning too slowly
- An exponent that is a slope, not a law
- A radius that decides what matter can be
- A shear layer that should have spread
- A spectrum that is a stack of temperatures
- A star held up by a rule about counting
- A star is held up by its own weight
- A star that tells its distance by how slowly it blinks
- A surface that slowed because the star grew
- A threshold with no free parameter in it
- A wind that takes no mass and all the spin
- Every note turns back at its own depth
- Mass decides everything, by a power of three and a half
- Most stars are small, and most of the light is not
- One step of memory kept at the poles
- The candle that has to be standardised
- The clock that starts by forgetting
- The companion survives, and it is moving
- The darkness a field pays for
- The diagram that sorted the stars, by plotting two things against each other
- The disc that has to throw angular momentum away
- The explosion that never reaches the surface
- The exponent no pulsar has
- The flow that narrows its own channel
- The furnace that runs cooler than a compost heap
- The interior read from a comb of frequencies
- The main sequence is a place stars sit, not a track they travel
- The mass a cold star cannot exceed
- The mass a star does not keep
- The only stars whose masses are known
- The only thing that leaves the centre
- The part of a star that boils
- The part of a star that never slowed down
- The resonance that had to exist
- The star that swells because its centre shrank
- The valve that has to sit at the right depth
- The wake and the meal are one calculation
- Three causes with three shapes in one curve
- Three clocks and a runaway
- Two explosions told apart by a missing line
- Two orbits of one pair, and a distance falls out
- Two radii, from a light curve alone
- Two scaling relations calibrated on one star
- Two stars only a Fourier transform can tell apart
- Why the biggest stars die first, and take the galaxy with them
- A core too heavy for the gas around it
- A survival that depends on the energy
- A ceiling on the light and not on the mass
- A lifetime that is still a forecast
- A distance that rests on one unmeasured number
- The same flux in three sizes
- A colour that runs backwards at the end of cooling
- A corona held by its field and opened by its gas
- The last fuels burn for the neutrinos
- A flow that piles up at the magic numbers
- Mechanics sets a star's temperature before fusion does
- The pulse that shows the back of the star
- Brighter for its mass and fainter for its colour
- A donor that grows as it is eaten
- The least known number in binary evolution
- Mass that leaves takes the orbit's spin with it
- A star tipped over at a thousand times its horizon
- A soft centre the rest of the core outvotes
- A field that waits for the core to freeze
- Too large and too cool by just enough to keep the light
- A precession slowed by stars lying on their sides
- A lever set by the dipole and not the field
- A rise a detector shrinks to a tilt
- A lone star is dated only as it leaves
- A Sun read through a shield that also changed
- A dynamo that did not need the shear layer
- A star that has to make its own catalyst
- A limit written for free electrons
- A turnover whose position is an age
- Four clocks and the stars none of them reads
- A star that distils itself as it freezes
- A scatter that points the way dust does
- An expansion clock read from the stars' motions
- A correction that grows as the fifth power of the frequency
- A metallicity term too small to close a gap
- A nebula that cannot be beamed at
- A lifetime that stops getting shorter
- A wind that carries the ledger of its loops
- A spot whose missing heat goes nowhere
- A binary that goes silent for an hour of period
Exoplanets
- A centroid that moves when the brightness does not
- A chain that could not have been assembled in place
- A companion on the same orbit, seen in the planet's clock
- A composition that dates a formation rather than placing it
- A duration that measures an eccentricity
- A forecast that fails on a schedule
- A gap in a histogram that says how planets are built
- A light curve with a fold in it
- A mass that is only a mass once the eccentricity is known
- A misalignment only cool stars forget
- An asymmetry that the Earth's own orbit puts in
- An event of a few hours and no host
- A planet measured by the light it removes
- A planet radius is a stellar radius
- A planet ten times larger in one colour
- A planet that was the star's own rotation
- A planet where one cannot form
- A radius no cold planet is allowed
- A radius that depends on the colour it is measured in
- A shadow crossing a rotating line
- A smaller star puts the valley lower
- A spectrum flattened by cloud, or by nothing
- A star magnified by a planet nobody will see again
- A star subtracted using the star
- A torque that nearly cancels
- A transit late by the width of an orbit
- A velocity measured from a shape
- Capture is a direction, not a strength
- Every survey draws a different sky
- Four contact points, and what they fix
- A planet that is never confirmed, only validated
- Nine orders of magnitude, half an arcsecond apart
- One density, and every planet that has it
- One number sets the zone
- One timing curve and five planets that could draw it
- Planets found by a transit running late
- The band moves and the orbit does not
- The envelope that doubles a planet lasts longest
- The gas a planet cannot keep
- The line beyond which ice counts as rock
- The part of a rate that is a definition
- The planet is seen when it disappears
- The planets that were not seen
- There is not one line, there is a staircase
- The shield that is also a funnel
- The star moves, and the mass is a lower bound
- The stripping runs ahead of the starlight that drives it
- The young Sun's spin decides what the Earth kept
- Two elements in a ratio, and a birthplace read off it
- Two methods, and one density
- Two systems that draw the same curve
- The threshold that is not a threshold
- Every method prefers a circle, and not for the same reason
- How many planets a star has is not a measurement
- A thermostat that only halves the error
- A year too short to feel its own eccentricity
- Steam before the zone existed
- A reference built from other stars
- The gas that turns round beside the planet
- A planet circularised at twice the distance that would destroy it
- One eccentric planet, or two circular ones
- An exposure time chosen by the star
- A null filled in by the star itself
- An escape that stops following the starlight
- A threshold that makes iron matter only to giants
- An angle hidden by the tilt of the star
- Molecules seen only through a change of temperature
- Dust that does not dim with distance
- More small planets round smaller stars
- At a year, most candidates are noise
- A peak that neither survey can see alone
- Every planet of a star must agree on its density
- A model of the star that can carry the planet
- A planet has one velocity in every colour
- A slope that is a whole curve of companions
- Water that remembers how cold it was
- A core that shut the door on the pebbles
- A spread the projection does not hide
- A transit that runs differently backwards
- More iron than the star could give
- A day side as hot as bare rock
- The Earth-sized bin is where diluted planets land
- A cadence that finds a planet is not one that weighs it
- The heaviest atom a hydrogen wind can lift
- A gap in eccentricity a density can only just see
- A fraction read in each channel's own units
- A helium line that weighs the star first
- A shoreline measured in light already spent
- A second peak the errors have to let through
- A zodi measured in heat and needed in light
- An envelope spent so an ocean could stay
- A clock that slows, or a star that falls
- A target list that counts pairs twice
- An envelope that boils down before the starlight strips it
- A neighbour an eccentric arrival cannot leave
- A peak that should move with the star
- A transit that says which star it crossed
- A planet read in the ashes of its star
- The stars that could catch the Earth in transit
- A moon read from how late and how long
- Water that is on the star and not the planet
Gravitation
- A cluster that boils itself away
- A core weighed by something that never went in
- A day five hours long
- A detector the size of the galaxy
- A distance tangled with an angle
- A distance with no ladder under it
- A drag computed with a logarithm nobody can pin down
- A drag that is strongest in the middle
- A drag with nothing to drag against
- A feeding zone, and the spacing it forces
- A heat flow that depends on a number nobody can compute
- A moon heated by not being allowed to relax
- An answer obtained along a path that was not taken
- An average that weighs what cannot be watched
- An edge is a balance, not a boundary
- An error that grows like a random walk
- An ocean is detected and its depth is not
- An orbit measured to be shrinking
- A pair that heats what is trying to cool
- A prediction with an expiry date
- A quality factor quoted without a period is half a number
- A rotation locked to the orbit, but not one to one
- A sphere pulls exactly like a point, and the proof is a pair of cones
- A spin that is one length in disguise
- A step that must not be adapted
- Every pair arrives circular
- Five places that keep station, in a problem with no solution
- Forty-three arcseconds, after everything else
- How long a system takes to forget
- How much a world gives
- Neither body is still, and the wobble is how planets are found
- Nothing in the sky is weighed in kilograms
- One heat flow, and two viscosities
- One number where two masses were
- Resonance clears a gap in one place and locks a moon in another
- The curve that says where a body cannot go
- The distance at which a moon stops holding together
- The Earth's shape, read off a satellite's node
- The field a satellite is allowed to feel
- The number that survives the encounter
- The part of a kick that heats nothing
- The part of a shape the spin cannot explain
- The period a star is pulled towards
- The region a planet may keep a moon in
- The second number a black hole has
- The surface a star stops at
- The system that gets hotter as it loses energy
- The tide is a difference, which is why there are two of them
- The tunnel that takes the same time from anywhere
- The weakest field changes the answer
- Three bodies, and what "no solution" actually means
- Two bodies replaced by one that does not exist
- Where the chaos comes from
- Whether the heavy material sank
- Wrong about where, and right about how much
- A ring whose size is almost only a mass
- A spin that is measured as an angular momentum
- A moon that two bodies could not have caught
- A stability limit with a notch cut in it
- A constant measured through a Sun that is getting lighter
- A disc that throws its spin upward
- A core that makes what the cluster asks for
- A barrier that leaks at a rate that can be computed
- The part of a delay no orbit can imitate
- An equilibrium reached without a single encounter
- Inside a ring the pull points outward
- Stars lost to a kick that adds no energy
- A third body kept at a safe distance
- The lightest body leaves
- A periodic orbit that the sky cannot keep
- The shell can be flattened if it thins at the poles
- A tide table is astronomy with the harbour fitted
- A mountain's gravity says what holds it up
- A slow shock heats the halo and robs the core
- A field the turbulence will not let in
- A disc that stores its inflow and spends it in a century
- A few thousand clouds outrun a hundred billion stars
- Torques that add because the orbits hold still
- A floor under the unseen companion
- A black hole weighed by a wobble on the sky
- The binaries a core keeps are spread evenly in energy
- Ejected from a globular, merged in a nucleus
- A chaotic orbit clings to the edge of order
- A gap that counting can test and impostors can fill
- A probability for a system with one future
- A shell outside the stream turns nothing
- A Love number measured at nuclear density
- A migration timed by the planet and not the moon
- A rare event reached by cloning the near misses
- A relaxation that stops before it is finished
- A ring that is thinner from one side
- A drag that stops where every orbit keeps time
- A ring weighed by the wave crossing it
- A population that cannot share the cluster's temperature
- Precessions bought one hertz at a time
- A constant bounded by the oceans
- The tide that holds up the deep ocean
- A moon the Earth does not hold
- Pairs of stars too loosely bound to survive heavy dark matter
- A particle on a line that can spell any word
- A force that can hide at any one distance
Orbits
- A collision dated by a scatter plot
- A comet that arrives a day early
- A cut-off period that is an age
- A drift rate that says what the surface is made of
- A family whose size is a choice
- Aiming at a plane instead of at a planet
- An acceleration that was the spacecraft's own heat
- An average that precession cannot move
- An eccentricity that cannot be zero
- An error that is nearly all in one direction
- An inclination that turns into an eccentricity
- An invariant that is only almost one
- An orbit can look exactly like a circle and still not be one
- An orbit moved by heat
- A resonance with the planet itself
- A surface dated by counting holes in it
- A wall with no size in it
- Elements that do not stay constant
- Equal areas in equal times, which is angular momentum in disguise
- Every orbit one force allows, and the number that picks between them
- Five directions and no distance among them
- Nine dates for every surface in the solar system
- Ninety-nine per cent of the mass and none of the spin
- No planet has an eccentricity of its own
- One equation for the speed anywhere, and the eccentricity is not in it
- One time of flight and five ways round
- Only two force laws let an orbit come back
- Six numbers that fix an orbit for all time, and the sixth is the awkward one
- The average depends on what is being averaged
- The bound that holds only in the linear theory
- The craters that were not primary
- The drag that sorts a disc by size
- The elements that stop existing
- The formula that exists, and is not used
- The law that links period to size, and weighs everything
- The one solve that does not ask which conic it is
- The orbit is an ellipse, and the Sun is not in the middle of it
- The orbit that has no period
- The position that has no formula, and is computed anyway
- The precession that switches the cycle off
- The series that is subtracted
- The singularity that is a change of variable
- The table that is a fit
- The third law is wrong by the mass of the planet
- The third thing that is conserved
- The wall that angular momentum builds
- The well moves, and the body keeps its share of it
- Three observations and no orbit at all
- Three rotations that put an orbit in space, and they do not commute
- Two places and a clock decide the path
- Where a planet is and where it is seen
- Where the mass is and where the light is
- Which direction moves which element
- A wall measures a ratio, and a ratio is a line
- Two damping times, one crossing, and the slope that separates them
- A split that decides whether the piece can leave
- A spin barrier with a corner in it
- A cycle that builds what the wave needs
- A ceiling the outer orbit imposes
- The size at which a body is easiest to break
- A hotter summer that is also a shorter one
- A spacing law that random orbits obey
- A kink that measures how deep the lava was
- A spike only first-time visitors can be in
- A denominator that emptied the inner belt
- An age read from angles that meet
- A ceiling that forgets how much there was
- An orbit that turns over
- Every fragment comes back through the same point
- The variable that makes Lambert's problem easy
- The size forgets how the mass was lost, and the shape does not
- An ice sheet that skips a beat of the tilt
- Eleven in a hundred by geometry, and the rest by waiting
- A fall is half an orbit with no width
- A census of visitors is a census of the survey
- A tilt the Moon should not have
- Four numbers that carry a state without an orbit
- A distant planet felt only as a stretch
- A Moon that would lean towards the Sun
- A kick speed read off the slope of a histogram
- A collision moves the cloud's centre, and an explosion cannot
- Jupiter keeps only the visitors already nearly bound
- The jet that pushes a comet also turns it
- A kick that writes over the record of the pulses
- A young surface dated by a handful of holes
- A deficit the giants hold and Mercury could borrow
- A surface that slides before the body sheds
- An orbit seen at an angle keeps everything but its focus
- An answer from two bodies, flown through a flattened Earth
- A correction that tilts the arc it meant to aim
- A check that cannot see the clock
- A wall that leans towards the body that damps
- A family checked by a colour it was not chosen by
- A tilt built from a thousand near misses
- A clock checked by the craters it is making now
- What Jupiter kept of the Sun's siblings
- Two clocks in the dust of one collision
- A shower that is a reading of an orbit
- A moonlet that weighs a pile of rubble
- A term too small to keep that a denominator kept
- A perigee that moved twice as fast as Newton