Science Study Guide

Science 3,779 clues | 471 recurring answers

Topic Overview Study Guide Practice

471

answers to learn

30 Must-Know

128 Should-Know

313 Worth Knowing

Quick Reference: Must-Know Answers

These appear 8+ times. Memorize these first.

gravity 21 hydrogen 20 Galileo 18 carbon 18 Sir Isaac Newton 18 carbon dioxide 15 liquid oxygen 15 Jupiter 14 chromosomes 14 Saturn 13 Albert Einstein 13 the Sun 12 Water 11 mercury 11 Mars 10 light 10 igneous 10 electrons 10 the electron 10 Pasteur 9 lead 9 helium 9 Dmitri Mendeleev 9 Uranium 8 tin 8 pressure 8 DNA 8 Archimedes 8 anthropology 8 absolute zero 8

Answers by Category

Chemistry / Elements

233 answers | 836 clues

Must-Know (13)

liquid oxygen 15x 20.0% stumper $500 avg J:5 DJ:10

J $300 1993 Used in rocket propulsion, LOX stands for this

DJ $600 1992 Cane sugar is a chemical compound consisting of carbon, hydrogen & this element

DJ $1,200 2010 Rocket pioneer Robert Goddard discovered the best liquid fuel was a combination of gasoline and this, aka LOx

chromosomes 14x 7.1% stumper $521 avg J:4 DJ:10

J $200 1997 Human beings normally have 46 of these in most of their cells

DJ $600 1996 They're the tiny threadlike structures that carry the genes - you have 23 pairs

DJ $1,200 2006 These DNA-bearing structures have caps called telomeres; learn to lengthen those & we'll all live forever

Albert Einstein 13x 7.7% stumper $354 avg J:6 DJ:7

J $200 2005 In 1933 he joined the Institute for Advanced Study in Princeton, N.J.; he became a U.S. citizen in 1940

DJ $600 1991 In 1905 he was the first to propose the existence of particles of light called photons

DJ $1,000 1997 In 1905 this physicist proposed that photons were the carriers of electromagnetic energy

light 10x $310 avg J:6 DJ:4

J $100 1994 When exposed to ultraviolet radiation, a phosphoric substance will emit this

J $600 2003 2001:Researchers produce pulses of this that last 650 billionths of a billionth of a second

J $200 2014 By definition, bioluminescence is the production of this by living organisms

electrons 10x 10.0% stumper $880 avg J:1 DJ:9

DJ $200 1996 In an atom these elementary particles spin around the nucleus

DJ $600 1988 From Greek for "amber", these subatomic particles were discovered in cathode rays in 1895

DJ $1,600 2011 The Schottky effect is a type of increase in the discharge of these subatomic particles from a heated surface

Pasteur 9x $689 avg J:4 DJ:5

J $400 2002 In 1888 this French bacteriologist founded an institute in Paris to continue his rabies research

J $600 2013 This 19th century chemist saved France's beer, wine & silk industries

J $1,000 2026 In the 1860s he presented to the French Academy of Sciences his work undermining the idea of spontaneous generation

lead 9x 33.3% stumper $978 avg J:4 DJ:5

DJ $200 1992 From the Latin plumbum, Pb is the chemical symbol for this

J $600 2015 This element is "le plomb"; get it out!

DJ $2,000 2024 About 1.5% of any quantity of the isotope uranium-238 decays to this element every 100 million years

Dmitri Mendeleev 9x 33.3% stumper $1,244 avg DJ:9

DJ $800 2000 This Russian chemist used his periodic law to predict the properties of 3 then unknown elements

DJ $1,000 2001 In 1869 this Russian chemist published his periodic table

DJ $1,000 2001 The element named for him wasn't one of the ones he left a gap for in the periodic table; it came in at 101

tin 8x $738 avg J:4 DJ:4

J $300 1998 You add this element to copper & zinc to get bronze

J $600 2021 Stannum is the Latin word for this, which explains Sn as its chemical symbol

J $1,100 DD 2019 The Latin word for this element is stannum

pressure 8x 25.0% stumper $2,538 avg J:2 DJ:6

DJ $400 1997 According to Boyle's Law, when a gas is compressed to half its size, this doubles

J $500 1988 The unit of measure for this force is the bar or millibar

DJ $1,200 2011 (Sarah of the Clue Crew gives the clue as she and Kelly demonstrate a potato gun.) A potato gun demonstrates Boyle's Law using a simple tube & a stick; pushing the stick reduces the volume of air & increases this 8-letter term, making the potato go b...

DNA 8x $543 avg J:1 DJ:6 FJ:1

DJ $400 2024 The novel "The Gold Bug Variations" has a double-stranded plot, intertwining Bach's music & cracking the code of this molecule

DJ $600 1993 The oldest strand of this substance extracted is from a 25-million-year- old termite

FJ 2013 For a 1953 paper Odile Crick drew the diagram showing the structure of this

Archimedes 8x 25.0% stumper $962 avg J:2 DJ:6

DJ $400 2024 A hydrostatic principle is named for this Greek who lived much of his life in Syracuse, Sicily, then a Greek city-state

J $500 1989 Known for his principle of displacement, he's been called "The Father of Experimental Science"

J $1,000 2022 This Greek gave his name to the law that says a body in fluid is acted on by force proportional to how much fluid it displaces

absolute zero 8x $538 avg J:3 DJ:5

DJ $400 2019 2-word name for what in theory is the lowest possible temperature

J $500 1984 Name given to temperature -273.15 C

J $1,000 2020 It's equal to -459.67 degrees Fahrenheit

Should-Know (71)

the mantle 7x $600 avg J:2 DJ:5

DJ $200 1996 It's the term for the portion of the Earth between the crust & the core

J $800 2024 What's called the Moho discontinuity inside the Earth separates the crust from this interior section

DJ $1,200 2022 This region of the inner Earth is prone tohot spots; volcanoes can form above them

metamorphic 7x 14.3% stumper $1,586 avg J:3 DJ:4

J $600 2022 Let's change the subject & talk about this class of rocks including gneiss & soapstone that gets changed atom by atom over time

J $900 DD 1999 Since limestone undergoes changes to become marble, marble is classified as this type of rock

DJ $600 1994 Changes in the Earth may eventually cause igneous & sedimentary rocks to become this type

lithium 7x 14.3% stumper $1,200 avg DJ:7

DJ $800 2021 It has atomic number 3 as the least dense of all metals & number 34 as a SiriusXM channel for '90s tunes

DJ $1,000 1994 This lightest of all metals was discovered by Swedish chemist Johann Arfvedson in 1817

DJ $800 2009 The major source of this treatment for bipolar disorder is mined in North Carolina

friction 7x $771 avg J:2 DJ:5

J $200 2018 It's the resistance that opposes the motion of one surface across another

DJ $800 2013 Hockey pucks are frozen before a game to reduce this motion-resisting force

DJ $1,200 2019 You can't use a Carnot engine to power your car--it's an ideal one that loses no heat via this resisting force

static electricity 7x 14.3% stumper $571 avg J:3 DJ:4

DJ $400 2006 (Kelly and Jon of the Clue Crew play with water in a laboratory; Kelly reads.) Run a comb through your hair & hold it here--the water is drawn to the comb because of this accumulation of electrical charge

J $600 2010 This can build up after a good hair brushing, & when you remove a wool hat, it can make your hair stand on end

DJ $1,200 2013 It's annoying when you walk across carpet & touch metal but helpful when Xerox machines use it to make copies

gamma radiation 7x 14.3% stumper $743 avg DJ:7

DJ $200 1993 In physics a rad is the unit used to measure the amount of this absorbed by matter

DJ $600 1997 It's measured in rads

DJ $1,000 1995 In physics, the 3 basic methods of heat transfer are conduction, convection & this

nuclear fission 7x 16.7% stumper $767 avg J:1 DJ:5 FJ:1

DJ $400 2009 In 1939 physicist Lise Meitner & her nephew Otto Frisch coined this term referring to the splitting of an atom's nucleus

DJ $600 1988 In biology it's cells splitting & making identical offspring, but in physics, it's nuclei splitting, making energy

DJ $1,600 2022 It's the process by which an atomic nucleus splits into 2 smaller nuclei, or how certain single-celled organisms reproduce

stem cells 7x 14.3% stumper $814 avg J:4 DJ:3

J $200 2007 These cells from human embryos can grow into any type of tissue & may someday cure diabetes & Alzheimer's

J $500 1984 Cytology is the study of these biological building blocks

J $1,000 2024 1965: Leonard Hayflick shows that these can divide & reproduce only a finite number of times before dying

Jean Foucault 7x 57.1% stumper $1,029 avg J:3 DJ:4

J $200 2009 The axial rotation of the Earth seems to shift the plane of motion of this scientist's pendulum

J $800 2026 The Central Rotunda of the Griffith Park Observatory showcases the pendulum experiment tried by this man in 1851

DJ $1,000 1991 This man, known for his pendulum, made the first gyroscope in 1852

silver 6x 16.7% stumper $383 avg J:3 DJ:3

J $100 1988 Something described as argentiferous contains or produces this metal

DJ $600 1985 The photographic industry is world's largest user of this precious metal

J $200 2021 Argentiferous means containing or producing this metal

salt 6x 33.3% stumper $683 avg J:4 DJ:2

J $100 1996 It's the more common name for sodium chloride

DJ $1,200 2021 Pass the this, defined as a substance produced by the reaction of a base & an acid

J $200 2010 To combat hypothyroidism, iodine was first added in the 1920s to this common seasoning

rubber 6x 33.3% stumper $467 avg J:3 DJ:3

J $100 1991 Vulcanization increases the hardness of this by heating it with sulphur

DJ $1,600 2024 In the 19th century Charles Macintosh mixed a solvent called naphtha with this substance to make a waterproof material

J $200 1991 Joseph Priestley gave this name to some tree sap that could wipe out pencil marks

Potassium 6x $683 avg J:3 DJ:3

J $300 1997 This second-lightest metal, symbol K, is so soft it can be cut with a knife

J $600 2022 Bananas have a tiny amount of radioactivity due to this element, which can emit .01 millirems of radiation

DJ $1,600 2009 "To protect taste" Diet Coke adds some "K" to the mix:this element

pollen 6x $350 avg J:4 DJ:2

J $200 2016 The ragweed variety of this material is seenhereunder the microscope--achoo!

DJ $600 1996 Honeybees get their sugar from nectar & their protein & fat from this

J $200 2009 Breezes often transfer these tiny grains from male flower parts to female seed cones

kinetic 6x $950 avg J:2 DJ:4

J $500 DD 1997 It's the type of energy a body possesses by virtue of its movement

DJ $1,000 1993 It's the type of energy exhibited by a flying baseball or an object falling to the ground

J $600 2018 This adjective from the Greek for "moving" describes the mechanical energy of an object due to motion

earthquakes 6x $200 avg J:5 DJ:1

J $100 1989 In the 1st century A.D. the Chinese invented the 1st seismometer to detect these

J $100 1987 Data from resistivity gauges, gravimeters, & creep meters are being used in efforts to predict these

J $200 2018 Curtains made of carbon fiber rods are specifically designed to help buildings withstand these

Darwin 6x $633 avg J:2 DJ:4

J $200 2013 He let his theory evolve for 20 years before going public in 1858

J $800 2007 8 years before "The Origin of Species" was published, this British naturalist wrote a paper on barnacles

DJ $1,200 2005 While serving as secretary of the Geological Society of London, 1839-41, he wrote the "Journal of Researches"

Celsius 6x 16.7% stumper $483 avg J:3 DJ:3

DJ $200 1995 In 1742 he described his centigrade thermometer before the Swedish Academy of Sciences

J $500 1985 Till later scientists reversed his scale, he said: 0º equals boiling, 100º equals freezing

J $400 2022 A Swedish astronomer gave his name to this temperature scale

algae 6x 16.7% stumper $400 avg J:4 DJ:2

J $100 1993 A botanist could tell you that algology is the study of these

J $500 2000 The monera kingdom consists of bacteria & the blue-green species of this

J $200 2008 One day soon we may go even greener with fuel made from these green goopy simple aquatic organisms

Niels Bohr 6x $1,200 avg J:1 DJ:5

J $800 2013 In 1957 this Danish physicist became the first recipient of the USA's Atoms for Peace Award

DJ $1,000 1996 This Danish physicist won a Nobel Prize in 1922 & his son won one in 1975

DJ $1,200 2008 In 1920, he was named director of the Institute of Theoretical Physics in Copenhagen

Enrico Fermi 6x $1,050 avg J:3 DJ:3

J $300 1988 While "FM" means frequency modulation, Fm is an element named for this Italian atomic physicist

DJ $1,000 1990 Element No. 100 was named after this Italian physicist

DJ $1,600 2004 He got through a pile of work between his birth in Rome in 1901 & his death in Chicago in 1954

a diamond 6x 16.7% stumper $417 avg J:1 DJ:5

DJ $200 1992 Carbonado is an impure form of this mineral used for drills & abrasives

DJ $800 1990 This mineral comes after No. 9, corundum, on the Mohs scale

DJ $400 2013 At 10, this mineral is the hardest on the Mohs scale

sulfur 5x 40.0% stumper $900 avg J:2 DJ:3

J $300 1996 This yellow element is found in gunpowder & matches & is used in vulcanizing rubber

DJ $1,000 1988 Nathaniel Hayward sold Chas. Goodyear his process for treating rubber with this element

J $400 1987 This element, No. 16, is always found near volcanoes, bringing true meaning to "fire & brimstone"

Rachel Carson 5x 40.0% stumper $740 avg J:2 DJ:3

J $200 1994 A friend whose bird sanctuary had been sprayed with DDT sparked her to write "Silent Spring"

DJ $800 1997 This author of "The Sea Around Us" taught zoology at the University of Maryland 1931-36

DJ $1,200 2011 During the depression, this marine biologist & ecologist wrote radio scripts for the U.S. Bureau of Fisheries

protons 5x 20.0% stumper $840 avg J:1 DJ:4

DJ $400 2022 The atomic number of an element is determined by the number of these in one atom of it

DJ $600 1999 Mass number is defined as the number of neutrons & these particles in an atom's nucleus

DJ $1,600 2008 (Kelly of the Clue Crew rubs a balloon on her hair in the Jeopardy!science lab.) Rubbing a balloon builds up electrons that then attract this type of particle in ametal can, from the Greek for "first"

natural selection 5x 60.0% stumper $680 avg J:1 DJ:4

DJ $400 1989 Darwin explained how the fittest of each species survived through this evolutionary process

DJ $600 1992 Darwinism is the idea that evolution took place by this process

DJ $1,200 2008 Darwin defined it as "preservation of favorable variations and the rejection of injurious variations"

iodine 5x 20.0% stumper $1,020 avg J:2 DJ:3

J $300 2000 While compounds of this element are added to table salt, in its pure form it's quite poisonous

DJ $800 1993 Seafood is a good source of this element necessary for the formation of thyroid hormones

DJ $1,600 2013 A bluish-black solid at room temperature, this halogen changes into a purple vapor when heated

Heisenberg 5x $1,400 avg J:1 DJ:4

DJ $800 2025 (Melissa Peterman presents the clue.) After being on "Young Sheldon" for 30-plus episodes, I can finally say it--a subatomic particle's position & momentum can't be accurately determined at the same time, sayshis Uncertainty Principle. Oh, that felt ...

J $1,000 2008 His uncertainty principle says a particle's position & momentum can't be known simultaneously

DJ $1,200 2024 In a 1927 paper he wrote, "We simply cannot know the present in principle in all its parameters"

heat 5x 20.0% stumper $680 avg J:1 DJ:4

DJ $400 2006 Combustion is an example of an exothermic reaction, one in which this is released

DJ $600 1991 A chemical reaction that absorbs this is endothermic; that gives it off, exothermic

DJ $1,200 2010 The second law of thermodynamics says that this will of its own accord only move to a colder object

glaciers 5x $220 avg J:3 DJ:2

J $100 1996 Drumlins are elongated, elliptical hills formed at the edges of these moving ice masses

J $200 1993 Erosion from these created fjords & drumlins

J $200 1991 The snow that falls on these moving ice masses goes through a stage called névé or firn

George Washington Carver 5x 20.0% stumper $840 avg DJ:5

DJ $400 2001 In 1897 this son of slaves discovered 3 new species of fungi which are named for him, including Taphrina carveri

DJ $800 2016 This Missouri man who loved to work for peanuts also developed a type of synthetic marble made from wood shavings

DJ $1,000 1987 Born in 1861, this scientist worked with Henry Ford to make rubber from milk of goldenrod

geology 5x 20.0% stumper $560 avg J:1 DJ:4

J $200 1998 The name of this science comes from 2 Greek words meaning "Earth discussion"

DJ $1,000 1984 Stratigraphy is a branch of this science

DJ $200 1993 Branches of this earth science include petrology & seismology

genes 5x $660 avg J:1 DJ:4

DJ $400 2013 In 2013 the Supreme Court ruled that human ones can't be patented, though synthetic versions can

J $500 1994 Barbara McClintock discovered that these can move from one place to another on plant chromosomes

DJ $1,600 2019 Jennifer Doudna & Emmanuelle Charpentier are co-inventors of the revolutionary tool CRISPR to edit these in the body

fermentation 5x 20.0% stumper $860 avg J:1 DJ:4

DJ $100 DD 1995 This is defined as the breakdown of glucose or other sugars by yeast or bacteria in the absence of oxygen

DJ $800 2021 Our pal Louis Pasteur used this word to describe what happens when yeast functions anaerobically

DJ $1,200 2007 Zymurgy is the chemistry branch that deals with this process in which sugar is converted into alcohol

ecology 5x 40.0% stumper $1,000 avg J:3 DJ:2

J $400 2016 Before global warming was a thing, Marvin Gaye put this -ology into the subtitle of his song "Mercy Mercy Me"

DJ $800 2017 It's the -ology associated with the symbol seenherethat was created back in the '60s

J $3,000 DD 2021 A German zoologist coined the name of this branch of biology that studies the relationship between organisms & their environments

coal 5x $640 avg DJ:5

DJ $200 1992 The main types of this fuel are peat, lignite, bituminous & anthracite

DJ $600 1990 Under pressure, peat turns into lignite & lignite becomes this

DJ $1,200 2015 A scrubber is a device primarily to remove sulfur before gases go up the smokestacks of plants burning this fuel

chlorophyll 5x $1,300 avg J:1 DJ:4

J $100 1997 This green plant pigment is also found in algae & in some bacteria

DJ $800 2009 The name of this green pigment found in plants is partly from the Greek for "green"

DJ $5,000 DD 2012 This pigment comes in different letter types; the C version is found in algae

ammonia 5x 60.0% stumper $1,160 avg J:1 DJ:4

J $400 1993 About 70% of this pungent gas produced is converted into fertilizer

DJ $600 1991 In the Haber process hydrogen & nitrogen combine to form this pungent gas

DJ $1,200 2011 The Haber process uses nitrogen & hydrogen to synthetically produce this pungent gas

a vacuum 5x $900 avg J:1 DJ:3 FJ:1

J $400 1990 Term for a space in which there are no atoms or molecules; a perfect one is unobtainable

DJ $1,200 2011 (Sarah of the Clue Crew performs a science demonstration.) You'd expect the paper to fly up when extreme pressure is applied, but instead... the wood breaks; air couldn't flow in quickly enough between the paper, the wood & the table, so a partial th...

FJ 2003 Some refractive index numbers for you now: diamond, 2.42; air, 1.0003, this, 1.0000

the nucleus 5x $520 avg J:2 DJ:3

J $200 2015 This part of a cell that contains the chromosomes is "le noyau"

DJ $600 1993 It's the most massive part of an atom

DJ $1,200 2003 In 1963 Maria Goeppert Mayer received a Nobel Prize in Physics for her "shell model" of this part of an atom

dark matter 5x 20.0% stumper $1,480 avg J:2 DJ:3

J $200 2015 It's scientific for "stuff"; dust in the atmosphere is the "particulate" type

DJ $800 2025 (Neil de Grasse Tyson presents the clue.) The protons, electrons & other particles we know make up only about 5% of the universe; there's about six times as much of this mysterious shadowy stuff out there & we'redoing our bestto understand it

J $1,000 2022 Liquids & solids are states of this that sit there; swirlons, such as flocks of birds, are parts of the newer concept of "active" this

an ion 5x 20.0% stumper $460 avg J:3 DJ:2

J $300 1997 It's defined as an atom or group of atoms that has an electrical charge

J $600 2019 This type of atom is formed by the loss or gain of electrons

J $400 1998 A neutral atom will become one of these when it gains or loses an electron

work 4x 50.0% stumper $1,275 avg DJ:4

DJ $800 2000 To scientists, it's force times distance; to Twain, it's "whatever a body is obliged to do"

DJ $1,200 2015 Force times distance gives you this, commonly expressed in joules

DJ $1,500 DD 1988 A foot-candle is a unit of illumination & a foot-pound is a unit of this

viscosity 4x $1,500 avg DJ:4

DJ $800 1992 The resistance of a fluid to flow; syrup has a greater degree of it than water

DJ $1,600 2016 (Jimmy of the Clue Crew shows an animation on the monitor.) Fluids vary in the degree of friction between their molecules, leading them to also vary in their degree of resistance to flow--this 9-letter word

DJ $1,600 2003 (Sarah of the Clue Crew demonstrates in the lab.) From the Latin for "sticky", it's the resistance of a fluid to flowing

tungsten 4x $1,250 avg DJ:4

DJ $800 2016 This metal was discovered by 2 Spanish chemists in 1783 in samples of the mineral wolframite

DJ $1,000 1997 This gray metal is used in spark plugs & x-ray tubes as well as filaments

DJ $1,600 2009 This dense element's name is from the Swedish for "heavy stone"; most of Europe calls it wolfram

theology 4x $450 avg J:2 DJ:2

J $200 2016 A Th.D. from Duke Divinity School is a doctor of this

J $800 2011 In 1512 Martin Luther earned the degree doctor of this

DJ $400 1993 Martin Luther & Albert Schweitzer held doctorates in this

the stratosphere 4x 25.0% stumper $700 avg J:2 DJ:2

J $400 2022 The troposphere is sandwiched between the earth & this next layer of the atmosphere

DJ $600 1992 To avoid storms in the troposphere, pilots often fly in this next layer of the atmosphere

J $1,000 2022 Some 25 miles in depth, it lies between the troposphere & the mesosphere

refraction 4x $1,200 avg DJ:4

DJ $400 2002 This bending of light as it passes from air into water results from its slower speed

DJ $800 1990 It is this phenomenon which causes white light to break into colors in a prism

DJ $1,600 2023 The ratio of the velocity of light in one medium to its velocity in another is called the index of this

optics 4x $1,100 avg J:1 DJ:3

DJ $600 1993 It's the branch of physics that deals with light & vision

J $1,000 2017 In 1704 Newton published a groundbreaking treatise on this science of light

DJ $800 1997 It's the branch of physics that deals with light & vision

neutrinos 4x 25.0% stumper $1,300 avg J:2 DJ:2

J $1,000 2024 The "Top 10 Erroneous Results" from Science News include a 2011 finding that these chargeless particles can outrace light

J $1,000 2018 First predicted in 1930, this particle with no charge goes through miles of matter without reacting with a proton or neutron

DJ $1,200 2021 Discovered in 1956, this subatomic particle with no charge & very little mass is part of a family of particles called leptons

neon 4x $3,550 avg DJ:4

DJ $200 1985 When excited, this gas glows red, which means our Jeopardy! sign gets excited often

DJ $800 2021 Rare on Earth except in signs, this gas with atomic number 10 is a top 10 element in abundance in the universe

DJ $3,200 DD 2011 The name of this noble gas is from the Greek for "new"

melanin 4x 25.0% stumper $725 avg J:3 DJ:1

J $100 1991 This dark pigment is produced by skin cells called melanocytes

J $800 2021 The color of the iris comes from this brownish-black pigment--the more there is, the darker the iris' color

J $1,000 2007 Want a safe & long-lasting tan? It may be possible with an implant that triggers production of this skin pigment

mass 4x 25.0% stumper $950 avg J:1 DJ:3

J $200 2011 Technically, the measure of a body's inertia is known as this property of matter

DJ $1,200 2017 The Higgs boson is what endows all elementary subatomic particles with this fundamental property of matter

DJ $400 2021 "m" represents this in Einstein's equation E=mc2

Marie Curie 4x $600 avg DJ:2 FJ:2

DJ $400 1996 In 1914 she became head of the Paris Institute of Radium

DJ $800 2016 In 1929 President Herbert Hoover presented her with a $50,000 check to buy a gram of radium for a Warsaw lab

FJ 2024 nobelprize.org says some papers of this scientist "are stored in lead boxes", a "legacy that is literally untouchable"

magnesium 4x 25.0% stumper $900 avg J:1 DJ:3

DJ $400 2017 This element, Mg, can be used in underwater flares because it can pull oxygen from the water when combusting

DJ $800 2007 This element, symbol Mg, occurs naturally in such minerals as dolomite & brucite

DJ $2,000 2024 No. 12 on the periodic table, it's the third-most plentiful structural metal in the world after aluminum & iron

Linus Pauling 4x 50.0% stumper $1,575 avg J:1 DJ:3

DJ $1,000 DD 2015 He didn't carry a blue security blanket when he won a Chemistry Nobel for research on the nature of chemical bonds

DJ $1,600 2024 In 1948 this vitamin C advocate found that the polypeptide chain would coil into a structure he called the alpha helix

J $1,700 DD 1997 In the 1940s this Nobel Prize winner & vitamin C advocate studied the structure of antibodies

hydrogen peroxide 4x 25.0% stumper $775 avg J:2 DJ:2

J $300 1991 You can use this compound. H2O2, as a disinfectant or to bleach your hair

DJ $2,000 2021 In addition to its acidity, one reason honey doesn't spoil is that an enzyme in bees helps produce this compound, H2O2, a germicide

J $400 1987 Oxide commonly used on scraped knees & dark roots

gas 4x 25.0% stumper $650 avg DJ:4

DJ $200 2000 Above its critical temperature, a liquid becomes this

DJ $1,600 2022 Boyle's law states that the pressure of this varies inversely with its volume at constant temperature

DJ $400 2023 According to Charles' law, the volume occupied by an amount of this state of matter is proportional to its temperature

enzymes 4x 25.0% stumper $875 avg J:4

J $400 2024 1833: Anselme Payen discovers diastase, aka amylase, the first of these proteins that catalyze chemical reactions

J $800 2022 These are proteins, such as hydrolase, that catalyze biochemical reactions

J $1,500 DD 1992 Proteins such as pepsin & rennin that act as catalysts in the body are termed these

entropy 4x 66.7% stumper $1,400 avg J:1 DJ:2 FJ:1

J $600 2017 In 1865 physicist Rudolf Clausius coined this term for the measure of disorder or randomness in a closed system

DJ $1,600 2023 German physicist Rudolf Clausius put in the work by introducing this term for the measure of molecular disorder in a system

FJ 2021 This word used to denote an irreversible dispersion of energy was coined in the 1860s to sound a bit like "energy"

dry ice 4x $325 avg J:1 DJ:3

J $100 1999 Solid water is ice; solid carbon dioxide has this 2-word name

DJ $600 1990 Solid carbon dioxide

DJ $200 1994 At -109 F°., solid carbon dioxide is more commonly called this

deuterium 4x 25.0% stumper $1,025 avg J:2 DJ:2

J $500 1994 Harold Urey won a 1934 Nobel Prize for his discovery of this isotope, also called heavy hydrogen

DJ $1,000 DD 1997 Hydrogen has 3 isotopes: protium, tritium & this one with a mass number of 2

J $600 2007 (Kelly of the Clue Crew delivers the clue from the lab.) Normally, an ice cube floats; this one, however, sinks right to the bottom because it's made of heavy water, or D2O; the D standing for this isotope

copper 4x 50.0% stumper $550 avg J:2 DJ:2

J $100 1991 Used for coins, cupronickel is an alloy of this & nickel

J $500 1985 Sterling silver is not pure silver but an alloy of silver and this metal

DJ $1,200 2008 This reddish metal is a main ingredient of both brass & bronze

Copernicus 4x 33.3% stumper $1,067 avg DJ:3 FJ:1

DJ $400 2005 This Pole died in 1543, days after receiving the first copy of his book "On the Revolutions of Heavenly Bodies"

DJ $800 2018 Cn is the symbol for an artificially produced radioactive element named for this astronomer

DJ $2,000 DD 2019 In 1543 the world revolved around this man who wrote "On the Revolutions of the Heavenly Spheres"

cloning 4x $600 avg J:2 DJ:1 FJ:1

DJ $200 1991 In vertebrates, it's the process of reproducing an entire organism from a single cell

J $600 2007 Scientists in Australia hope to resurrect the extinct Tasmanian tiger by using genetic fragments & this method

J $1,000 2017 Asexual reproduction, a cell duplicating itself, is nature's version of this controversial practice

calcium carbonate 4x 25.0% stumper $975 avg J:1 DJ:3

J $300 1992 Chalk & limestone are naturally occurring forms of this compound, CaCO3

DJ $800 1990 CaCO3, it's the main ingredient in limestone

DJ $1,200 2023 This 2-word compound is the main component of both limestone & coral reefs

blue 4x $675 avg J:2 DJ:2

J $200 2003 The primary colors are red, yellow & this

J $500 1992 Cyanosis, a condition where oxygen in the blood is low, turns the skin this color

DJ $1,600 2021 When dipped in a solution with pH above 8.3. litmus paper turns this color

atoms 4x $550 avg J:2 DJ:2

J $200 1985 A 5th C. B.C. Greek philosopher was 1st to theorize that all matter is made of these

J $800 2012 (Kelly of the Clue Crew shows us molecular models in the lab.) We're using models of ethanol to show the 2 basic types of molecular models; 1 clarifies the bonds between these particles, while the other shows better what the molecule looks like in ac...

DJ $400 1991 About 400 B.C. Democritus wrote that matter is made of tiny bits of material he called these

aluminum 4x 25.0% stumper $400 avg J:2 DJ:2

DJ $200 1991 While it makes up more of the earth's crust than iron, its ore, bauxite, is rarer than iron ore

J $500 1998 To produce this metal using the Bayer Process, you begin with caustic soda & bauxite

DJ $400 1986 The oxide of this common lightweight metal forms rubies & sapphires

a molecule 4x $400 avg J:2 DJ:2

J $400 2011 O2is a diatomic one of these units of a pure substance; H2O is polyatomic

DJ $400 2009 (Sarah of the Clue Crew holds up a sugar cube.) At sea level, at 32 degrees Fahrenheit, 1 cubic centimeter of air, the size of a sugar cube, contains45 billion billionof these, from the Latin for "little mass"

DJ $400 1994 It's the smallest particle of a compound that has the properties of the compound

(Ivan) Pavlov 4x $600 avg J:1 DJ:3

DJ $400 2013 By ringing a bell, this Russian physiologist made dogs drool even if they couldn't see food

J $600 2005 The director of St. Petersburg's Institute of Experimental Medicine until his 1936 death; his name ring a bell?

DJ $600 1995 At the Institute of Experimental Medicine, he studied apes as well as salivating dogs

Worth Knowing (149)

zinc 3 time 3 the lanthanides 3 The Human Genome Project 3 the Doppler effect 3 Tesla 3 temperature 3 teeth 3 smell 3 rust 3 rocks 3 quarks 3 Quantum 3 protein 3 pasteurization 3 parapsychology 3 Paleozoic 3 ozone 3 osmosis 3 ornithology 3 order 3 Oppenheimer 3 neurons 3 momentum 3 microwaves 3 microwave 3 metamorphosis 3 Meiosis 3 Linnaeus 3 lactic acid 3 ionization 3 insulin 3 Half-life 3 green 3 graphite 3 gold 3 glass 3 evolution 3 covalent 3 cosmology 3 calcium 3 buoyancy 3 bonds 3 birds 3 atomic number 3 amino acids 3 Alfred Nobel 3 acoustics 3 a seismograph 3 a Petri dish 3 a cell 3 a caldera 3 zirconium 2 yogurt 2 yellow 2 Vaporization 2 up 2 turbulence 2 trees 2 transfer 2 torque 2 TNT 2 thrust 2 Thomas Edison 2 thermodynamics 2 the weather 2 the uncertainty principle 2 the periodic table 2 the Large Hadron Collider 2 The Island of Dr. Moreau 2 the fallopian tubes 2 the epicenter 2 the dew point 2 surface tension 2 string theory 2 spontaneous 2 smelling salts 2 sleet 2 silicon 2 roentgen 2 Robert Boyle 2 RNA 2 ribonucleic acid 2 reaction 2 radon 2 radioactivity 2 precipitation 2 platinum 2 pitchblende 2 physiology 2 phylum 2 phosphorus 2 pharmacology 2 pH 2 penology 2 nucleotides 2 nitrous oxide 2 nitric acid 2 nickel 2 Neutral 2 mutations 2 molecules 2 mole 2 mimicry 2 Michael Faraday 2 metric system 2 metals 2 Mendel 2 manganese 2 magnetic 2 Lymphocytes 2 leukemia 2 lemmings 2 Lavoisier 2 lava 2 krypton 2 Joseph Priestley 2 isotope 2 iridium 2 invertebrates 2 hydrochloric acid 2 hemophilia 2 hemoglobin 2 Heart 2 geothermal 2 gamma rays 2 Fortran 2 formaldehyde 2 eyes 2 Extinction 2 evaporation 2 equilibrium 2 entomology 2 energy 2 elements 2 electrolytes 2 electrolysis 2 eczema 2 economics 2 ductile 2 drag 2 delta 2 DDT 2 cumulonimbus 2 cosmetology 2 condensation 2 combustion 2 Columbia 2 citric acid 2

Astronomy / Space

95 answers | 499 clues

Must-Know (16)

gravity 21x $440 avg J:10 DJ:10 FJ:1

J $100 1996 g. Acceleration due to this, varies slightly with latitude since the Earth is not a perfect sphere

J $500 1991 Geotropism is the response of living things to the effects of this force

J $1,000 2007 At the Earth's surface, this force produces acceleration of about 32 feet per second per second

hydrogen 20x $555 avg J:11 DJ:9

J $100 1993 It's the element whose atomic weight is closest to its atomic number

J $500 1987 The name for this gas comes from the French for "water former"

DJ $2,000 2008 (Kelly of the Clue Crew shows some punctured metal tiles.) To evaluate materials likeshuttle shielding, projectiles are fired at speeds up to 16,000 miles per hour using this simple gas, compressed

Galileo 18x 5.6% stumper $567 avg J:5 DJ:13

J $200 2015 (Jimmy of the Clue Crew, at Harvard University's Historical Scientific Instruments, holds a metal right angle with a plumb bob.) One instrument, a geometrical & militarycompass, was used to find areas & volumes, & even determined how best to load & a...

DJ $600 1995 Around 1590 he formulated the law of falling bodies, s=1/2gt squared

DJ $1,200 2024 This Italian scientist's legendary falling bodies experiment showed falling objects accelerate at the same rate

carbon 18x 22.2% stumper $856 avg J:7 DJ:11

J $100 1998 By definition, organic compounds must contain atoms of this element

DJ $600 1991 The black charred surface on your toast this morning is this element

J $1,000 DD 2003 This element's name is from the Latin for "charcoal"

Sir Isaac Newton 18x $478 avg J:10 DJ:8

J $200 2022 He published the landmark treatise "Opticks" in 1704

J $500 1987 Universal gravitation & calculus were 2 of his many discoveries

J $300 1994 He formulated his 3 laws of motion in 1687

carbon dioxide 15x 13.3% stumper $333 avg J:9 DJ:6

J $100 1993 In breathing it's the gas you expel to the atmosphere

J $600 2008 (Cheryl of the Clue Crew performs a science experiment.) By mixing baking soda, a chemical base, with the acid in the lime juice, this gas is produced, resulting in a bubbly liquid

J $200 2026 Dry ice is what we commonly call the solid form of this gas

Jupiter 14x 7.1% stumper $1,413 avg J:8 DJ:6

J $100 1996 You could put all the other planets inside this planet & still have room to spare

J $500 1986 Heinrich Schwabe not only studied sunspots, but discovered the "Great Red Spot" on this planet too

DJ $1,000 DD 2019 Named for the man who first observed them, the "Galilean satellites" are the 4 largest moons of this planet

Saturn 13x 7.7% stumper $754 avg J:5 DJ:8

DJ $200 1997 In 1857 James Clerk Maxwell concluded that its rings were made of small, unconnected particles

J $1,000 2019 This planet is less dense than water--but it's still 95 times the mass of the Earth

DJ $200 1990 In 1675, Italian astronomer Gian Domenico Cassini discovered a dark gap in this planet's main ring

the Sun 12x 8.3% stumper $317 avg J:6 DJ:6

J $200 1998 About 4.5 billion years old, it's the closest G2 type star to where you're standing

DJ $800 1985 A heliologist can really get burned by studying this

DJ $1,200 2009 Usually seen daily by most people, it produces 3.83 x 1026watts of power in the form of light

Water 11x 9.1% stumper $373 avg J:5 DJ:6

J $100 2001 The Earth is the only planet in our solar system to have 2/3 of its surface covered by this

DJ $600 1987 Hydrates are defined as compounds containing molecules of this

J $100 1993 A hydrate contains this compound weakly bound in its crystals

mercury 11x 27.3% stumper $791 avg J:4 DJ:7

DJ $200 1997 From the surface of this innermost planet, the sun appears 2.5 times as large as it does from Earth

J $500 1999 A millimeter of this element is a common unit for measuring pressure, including blood pressure

DJ $1,000 1993 Estimated temperatures on this planet range from 950° F. on the sunlit side to -346° on the dark side

Mars 10x 10.0% stumper $390 avg J:6 DJ:4

DJ $200 2001 This planet, once wrongly thought to have canals, may have water at its surface after all

J $1,000 DD 2002 In the 1780s William Herschel determined its axial inclination & found it had ice caps

DJ $200 1987 Studying this planet in 1877, Schiaparelli called the lines he saw "canali" meaning "channels"

igneous 10x 10.0% stumper $820 avg J:4 DJ:6

J $200 1993 Of the 3 main classes of rock, this one is further divided into plutonic & volcanic types

DJ $600 1990 This class of rocks formed by the solidification of molten rock includes basalt & granite

DJ $1,200 2008 Of the 3 main classes of rock, this one is further divided into plutonic & volcanic types

the electron 10x 10.0% stumper $600 avg J:5 DJ:5

DJ $200 1997 In 1913 Robert Millikan became the first to precisely measure the charge of this negative atomic particle

J $500 1991 A positive ion is formed when an atom loses one or more of these

DJ $1,000 1994 It was the first subatomic particle discovered

helium 9x 37.5% stumper $538 avg J:2 DJ:6 FJ:1

DJ $400 DD 2015 The exosphere, the edge of the atmosphere, is primarily made of particles of hydrogen & this element

J $500 1996 It has the lowest boiling point of any element, -452 degrees Fahrenheit

FJ 1985 From name of Greek sun god, it is the 2nd most abundant element in the universe

Uranium 8x 25.0% stumper $888 avg J:3 DJ:5

DJ $200 1985 Heaviest element found in nature, named for a planet

J $500 2001 In 1911 Arthur Holmes used the decay of this element to lead to measure the age of the Earth

DJ $1,600 2024 The Encyclopedia Britannica calls it the most important of the actinoids

Should-Know (36)

iron 7x 14.3% stumper $471 avg J:4 DJ:3

J $100 1995 Ferrovanadium is an alloy of vanadium & this metal

J $1,000 2004 Scientists figure Mars isn't creme-filled, but has a liquid core made of this

DJ $200 1987 After aluminum, it's the 2nd most abundant metal in the earth's crust

inertia 7x 14.3% stumper $1,514 avg J:4 DJ:3

J $400 2016 A long pole helps a tightrope walker by increasing this tendency of a body to stay at rest

DJ $600 1991 It's the tendency of a body to resist a change in its state of motion

DJ $3,000 DD 2018 Newton's 1st Law of Motion, known as the Law of this, is why a car crash throws you into the windshield--buckle up!

Uranus 6x 16.7% stumper $667 avg J:3 DJ:3

J $400 2015 (Sarah of the Clue Crew, at Harvard University's Historical Scientific Instruments, shows an enclosed clockwork model.) Clockmaker Joseph Pope was about halfway through his 12-year project of building a gear-drivenmodelof the Solar System that showed...

DJ $600 1986 The 7th planet, which was 1st named the "Georgian Star" in honor of Britain's reigning monarch

DJ $1,000 1992 William Herschel earned a pension from King George III after discovering this planet in 1781

Ultraviolet 6x 16.7% stumper $533 avg J:3 DJ:3

J $100 1999 In weather forecasting, the UV index refers to the intensity of this type of radiation

DJ $2,000 DD 2013 Defined as 10-400 nanometers on the spectrum, these rays fall between visible light & X-rays

J $100 1996 Germicidal lamps emit these rays

the Big Bang 6x $620 avg J:1 DJ:4 FJ:1

J $300 1986 The Hubble constant tells how fast the universe is expanding since this "noisy" event occurred

DJ $1,600 2018 Gravity became its own force during the rather brief grand unification era, from 10-43to 10-35seconds after this

FJ 2005 Sky & Telescope magazine's contest to replace this term for a single event got 13,000 entries, but chose none

photosynthesis 6x $533 avg J:1 DJ:5

DJ $200 1992 Structures called chloroplasts are the main sites for this process in green plants

DJ $600 2001 Oceanic bacteria may convert sunlight to energy with this process, like plants

DJ $1,200 2011 A variety of Atlantic sea slug eats algae, retains some of it & can then undergo this plant process

Nitrogen 6x $700 avg J:1 DJ:5

J $400 1992 Ammonia, widely used as a refrigerant & cleaner, is composed of hydrogen & this element

DJ $600 1997 All amino acids contain carbon, hydrogen, oxygen & this element

DJ $1,200 2016 The New Horizons probe showed glaciers on Pluto made of this element that's 4/5 of Earth's atmosphere

methane 6x $1,033 avg J:2 DJ:4

J $600 2015 CH4, it's the chief constituent of natural gas

DJ $1,000 1985 The main part of natural gas, it's sometimes called marsh gas or firedamp

DJ $600 2001 (Sofia of the Clue Crew reports from the La Brea Tar Pits in Los Angeles.) The bubbling seen here is caused by this gas, a major part of Jupiter's atmosphere

black holes 6x 60.0% stumper $1,200 avg J:2 DJ:3 FJ:1

J $600 2020 In 2017 scientists recorded ripples in space-time called gravitational waves, which emerged when 2 of these collided

J $1,000 2016 In 2015 astronomers found 2 giant ones orbiting each other at the center of a nearby quasar

FJ 2024 Physicist John Wheeler said he coined this term as a faster way to say "completely collapsed objects"

3 6x 16.7% stumper $617 avg J:2 DJ:4

J $300 1987 Copernicus placed the sun in the center of the universe & the Earth this many planets out

DJ $600 1987 # of stars in the "belt" of the constellation Orion

DJ $1,200 2020 A Feb. 1953 paper by Linus Pauling says the structure of DNA involves this many "intertwined helical polynucleotide chains"--so close

Venus 5x $560 avg J:4 DJ:1

J $300 1996 After the sun & moon, this planet is the brightest object in the sky

DJ $800 2024 Radar images taken by the Magellan spacecraft in the 1990s helped determine that this planet has around 85,000 volcanoes

J $1,000 2004 Brighter in the night sky than any star is this planet that comes closest to the Earth

the core 5x $680 avg DJ:5

DJ $400 2010 The part of a pear with the seeds

DJ $600 1996 The sun's energy is produced in this central region

DJ $1,200 2025 Dynamo theory says that movement of liquid iron in this part of the Earth creates the planet's magnetic field

Pluto 5x 20.0% stumper $700 avg J:1 DJ:4

J $100 1997 This ninth planet's unusual orbit sometimes brings it closer to the sun than the eighth planet

DJ $600 1985 In 1930, 24-year-old astronomer Clyde Tombaugh discovered it

DJ $1,200 2003 In 2002 an 800-mile-diameter planetoid called Quaoar was found 1 billion miles past this 1430-mile-diameter planet

plasma 5x $700 avg J:2 DJ:3

J $300 1988 It's the clear, almost colorless, liquid part of the blood, or the highly ionized "4th state" of matter

DJ $1,200 2023 The phenomenon of St. Elmo's fire familiar to sailors & aviators is a luminous glow of this 4th state of matter

J $400 2017 This liquid straw-colored part of blood consists of about 90% water

paleontology 5x $1,040 avg J:3 DJ:2

J $400 2001 From the Greek meaning "study of ancient existence", it's the study of prehistoric plants & animals from fossil remains

DJ $600 1994 O.C. Marsh, a discoverer of Pterodactyl fossils, became the USA's first professor of this science in 1866

J $1,000 2007 The study of fossils, as from a T-rex

milk 5x $380 avg J:3 DJ:2

J $100 1987 In the platypus, this is secreted through pores in the mother's abdomen & lapped up by the young

J $500 1988 Casein, the main protein in this liquid, is used to make buttons

DJ $200 1993 In 1780 Carl Scheele isolated lactic acid in this substance that had soured

a comet 5x $480 avg J:1 DJ:4

J $400 2021 C/1847 T1 is the formal name of one of these astronomical objects

DJ $800 2019 A coma is the hazy atmosphere of gases that forms around one of these as it nears the sun

DJ $400 2016 Ison, one of these space travelers, was called a "sungrazer", passing within 684,000 miles of the surface

escape velocity 5x $1,320 avg DJ:5

DJ $1,200 2016 (Sarah of the Clue Crew drops an egg and it goes "splat".) To calculate the speed of a falling egg from a resting position, use V = G x T, where T is time, G is the acceleration of gravity, measured at 32 feet per second squared, & V stands for this

DJ $1,200 2015 "V" is for this, defined as the speed & direction of motion of a moving body

DJ $2,000 2006 Speed can be expressed with a number; this vector, combining speed & direction, often needs an arrow

the Moon 5x $280 avg J:2 DJ:3

DJ $200 2001 It's the celestial object on which you'd find Tycho, Oceanus Procellarum & Mare Imbrium

DJ $200 1997 In a month an observer can see 59% of this heavenly body's surface

J $300 1997 Around 1840 chemist John William Draper took the first photograph of this heavenly body

The Martian Chronicles 4x 25.0% stumper $700 avg J:2 DJ:2

J $200 2017 Published in 1950, these Ray Bradbury "Chronicles" begin in 1999, when men leave Earth to colonize a nearby planet

DJ $800 2016 "Chroniques martiennes"

J $1,000 2009 This Ray Bradbury collection of linked short stories includes "The Earth Men" & "The Moon Be Still As Bright"

Stephen Hawking 4x $1,450 avg DJ:4

DJ $600 1997 In 1993 he made a "brief" appearance as himself on an episode of "Star Trek: The Next Generation"

DJ $1,600 2026 The radiation named for this man is theoretically emitted by the space-time around a black hole

DJ $1,600 2002 During the 1970s this British physicist made the unexpected discovery that black holes emit thermal radiation

starch 4x 25.0% stumper $850 avg J:1 DJ:3

J $600 2020 (Sarah of the Clue Crew shows high-speed photography of a popcorn kernel popping on the monitor.) Pressure of about 135 pounds per square inch is needed to pop each popcorn kernel; the pressure comes from steam, created when this white carbohydrate i...

DJ $1,200 2004 Gerty Theresa Cori won a Nobel Prize for finding an enzyme that helps the body turn this into sugar

DJ $800 2025 Key to French fries: get the outside crispy while making fluff out of this, one of the 3 main types of carbs along with sugar & fiber

Sputnik 4x $625 avg J:2 DJ:2

DJ $200 1995 K. Tsiolkovsky, who predicted space travel, would have been 100 when this was launched in October 1957

DJ $1,600 2008 The Space Age began in 1957 when Russia launched this satellite

J $300 2000 Alfred Lovell's Jodrell Bank radio telescope was finished in 1957 just in time to track this 1st artificial satellite

Sirius 4x 50.0% stumper $1,300 avg DJ:4

DJ $1,000 1997 The name of this dog star, the brightest star in the night sky, is Greek for "scorching"

DJ $1,000 1996 The small companion to this "Dog Star" was the first star identified as a white dwarf

DJ $1,600 2026 Canopus is the second-brightest star in the night sky; this one is first

Neptune 4x 50.0% stumper $850 avg J:1 DJ:3

DJ $200 1990 The fourth largest planet in our solar system, it's usually next to last from the sun

DJ $800 2006 Geysers of what is probably nitrogen rise as high as 5 miles on Triton, this planet's largest moon

DJ $2,000 2004 In the 1940s Gerard Kuiper discovered Miranda, a moon of Uranus & Nereid, a moon of this planet

infrared 4x 25.0% stumper $875 avg J:2 DJ:2

J $300 1993 The IRAS telescope, which discovered 5 comets, made its observations in this spectrum of light

DJ $800 1985 Night-sight gun scopes measure heat radiation in this range

DJ $2,000 2021 The so-called whitest paint has been created to help combat global warming by radiating this "colorful" band of the spectrum

Hubble 4x 25.0% stumper $1,700 avg J:1 DJ:3

J $300 1991 Though its mirror is flawed, this $1.5 billion space telescope is producing useful data

DJ $500 DD 2005 The ratio of the speed of galaxies to their distance from Earth is the "constant" named for this astronomer

DJ $2,000 2020 The expansion rate of the universe is the constant named for this man, who in the 1920s pegged it at 7 times the current estimate

Halley's Comet 4x 33.3% stumper $1,067 avg J:1 DJ:2 FJ:1

J $400 1996 When astronomers got a close-up look at this object in 1985-86, its nucleus looked like a big potato

DJ $1,200 DD 1996 Bruce Morton & Francis Reddy wrote books on it in 1985; we'll probably see more books on it in 2061

FJ 2023 A craft that visited it was named for Giotto, based on the story that 680 years earlier, the painter depicted it as the Star of Bethlehem

Fahrenheit 4x $550 avg DJ:4

DJ $400 2018 In the 1700s he developed the first practical mercury thermometer & the temperature scale that bears his name

DJ $600 1987 German-Dutch instrument maker who came up with a glass thermometer filled with mercury

DJ $400 2004 This thermometer developer discovered that the boiling point of a liquid varies with atmospheric pressure

clouds 4x $200 avg J:2 DJ:2

J $100 1996 Fractus, congestus & humilis are terms used to describe these aerial formations

J $100 1993 Nephology is the branch of meteorology that studies these, nimbus or otherwise

DJ $200 1997 In 1803 Luke Howard coined names for types of them, including cumulus & stratus

astrology 4x 25.0% stumper $325 avg J:3 DJ:1

J $100 1992 It deals with the influence of the stars & planets on a person's life

J $600 2003 In 1585 Pope Sixtus V condemned the practice of this; wonder if anyone saw that coming?

J $200 1996 This study of the supposed effect of the stars on human life could be called zodiacology

4 4x $800 avg DJ:4

DJ $200 1989 In his relativity theory, Einstein proposed a space-time continuum made up of this many dimensions

DJ $600 1989 The number of planets in our solar system larger than the Earth

DJ $2,000 2021 In a molecule of sulfuric acid, there are this many atoms of oxygen

2 4x 25.0% stumper $225 avg J:2 DJ:2

J $100 1989 A little harder than talc, but not as hard as calcite, gypsum is this number on the Mohs scale

DJ $200 2001 The only even prime number

J $200 1988 Minimum number of lenses you need to make a simple refracting telescope

the solar wind 4x 25.0% stumper $1,850 avg J:1 DJ:3

J $200 2000 Ventifacts are rocks that are shaped by sand driven by this force of nature

DJ $2,000 2007 When the Earth's magnetosphere interacts with this flow of charged particles from the sun, auroras are produced

DJ $3,600 DD 2021 The Sun's corona propels this stream of particles continuously at hundreds of miles per second

the Earth 4x $425 avg J:2 DJ:2

J $100 1992 The mean distance of this planet from the Sun is one astronomical unit

DJ $800 1995 Geodesy is a scientific branch concerned with the exact shape & size of this

J $400 2003 Traveling 1 astronomical unit from the Sun, you should just reach this planet

Piltdown Man 4x $967 avg J:1 DJ:2 FJ:1

J $100 1986 The only animal that has walked on the moon

DJ $800 1985 Discovery of this "ancient man" in England proved to be a hoax

DJ $2,000 2009 No one knows who planted this fossilized "man" in an English dig, setting the study of evolution back decades

Worth Knowing (43)

the universe 3 the time machine 3 the Milky Way 3 the corona 3 the atmosphere 3 sunspots 3 Ptolemy 3 Orion 3 Isaac Asimov 3 gypsum 3 glucose 3 fusion 3 Edward Teller 3 diamonds 3 Ceres 3 archaeology 3 antimatter 3 a tsunami 3 a polymer 3 6 3 white 2 Wernher von Braun 2 ultraviolet rays 2 Titan 2 tides 2 the twilight zone 2 the solstice 2 the Mesozoic 2 the Hubble telescope 2 the Hubble Space Telescope 2 space 2 rocket science 2 Robert Heinlein 2 rings 2 retrograde 2 red 2 parsec 2 Mars & Jupiter 2 magnetic field 2 heliocentric 2 gamma 2 galaxies 2 convection 2

Biology / Animals

57 answers | 154 clues

Must-Know (1)

anthropology 8x 12.5% stumper $1,700 avg J:5 DJ:3

J $200 2023 Physical & cultural are branches of this "study of humans"

DJ $600 1996 Franz Boas & Margaret Mead were experts in this field

DJ $1,600 2024 At Brown Jessaca Leinaweaver, the chair of this department aims to study "humanity, past & present"

Should-Know (8)

amber 7x 14.3% stumper $771 avg J:4 DJ:3

J $100 1997 This fossilized resin from prehistoric pines can preserve an insect forever

J $500 1987 Term for the fossilized resin from prehistoric pines

J $1,000 2005 William Gilbert coined the word electricity, which comes from the Latin word for this fossil resin

photons 5x 20.0% stumper $780 avg J:2 DJ:3

J $500 1992 American Arthur Compton's work proved the existence of these "particles" of light

DJ $1,000 1996 Quantum optics is the branch of optics that deals with these particles of light

J $600 2024 The hypothetic also lar sailon a spaceship wouldn't fly on solar wind, as you might think, but on these particles, also known as light quanta

bees 5x $360 avg J:2 DJ:3

J $200 2004 Buzz in if you know that apiology is the study of these

DJ $400 2024 Karl von Frisch painted these insects to track their movements & show how they twerk their way to pollen

DJ $400 2010 Karl von Frisch won a Nobel Prize for work on animal behavior patterns, largely using the "dance' of this insect

yeast 4x $550 avg J:2 DJ:2

DJ $400 2024 Fundamental discoveries about how cancer cells proliferate came from study of the baker's type of this organism

DJ $1,000 1992 The enzyme zymase allows these one-celled organisms to convert sugar into alcohol & CO2

J $400 2006 (Jon of the Clue Crew reports from Copenhagen, Denmark.) In 1883, Carlsberg developed Saccharomyces carlsbergensis, a special strain of this to ferment the sugars in beer

Max Planck 4x 25.0% stumper $1,250 avg DJ:4

DJ $800 2001 In 1930 this originator of the quantum theory became president of the scientific society later renamed for him

DJ $1,000 1991 In 1900 this German physicist put forth his Quantum Theory

DJ $1,200 2025 The "Max" smart scientists at this institute in Cologne finished sequencing the domestic potato genome

Luther Burbank 4x 66.7% stumper $300 avg J:2 DJ:1 FJ:1

J $200 1997 In 1875 this plant breeder moved to California using profits earned on his potato

J $500 DD 2004 In the 1930s this California transplant posthumously received plant patents No. 12-16

FJ 1992 In 1927, a year after his death, his autobiography "Harvest of the Years" was published

genetics 4x $350 avg J:3 DJ:1

J $100 1993 This branch of biology deals with the principles of heredity

J $500 1988 It's the branch of biology dealing with heredity

DJ $400 2019 Gregor Mendel is referred to as the father of this field, the science of heredity

the eye 4x $350 avg J:3 DJ:1

J $100 1990 An ophthalmologist specializes in this part of the body

DJ $800 2022 The epicanthus is a fold of skin at the inner corner of this part of the human body

J $200 1997 Used to control glaucoma, a trabeculectomy is a procedure that reduces pressure in this organ

Worth Knowing (48)

the crust 3 talc 3 plankton 3 Mary Leakey 3 lactose 3 herpetology 3 fungi 3 fingerprints 3 Chaos 3 caffeine 3 amphibians 3 adrenaline 3 a laser 3 Zoology 2 zombies 2 worms 2 warm-blooded 2 ultrasound 2 turtles 2 trilobites 2 the Labrador Current 2 The Double Helix 2 The Beagle 2 tetanus 2 taxonomy 2 static 2 spleen 2 sickle-cell anemia 2 relativity 2 platelets 2 perennial 2 Ostrich 2 nicotine 2 microbiology 2 Margaret Mead 2 lichens 2 Jane Goodall 2 insects 2 indigo 2 Independence Day 2 ichthyology 2 hares 2 gneiss 2 Gills 2 eggs 2 Dian Fossey 2 cube 2 coral 2

Other

34 answers | 83 clues

Should-Know (3)

Psychology 7x 16.7% stumper $933 avg J:2 DJ:4 FJ:1

J $400 2019 A 2016 web article for the magazine this -ology Today addressed the "Is it a science?" debate & said yes

DJ $2,000 2024 William James' 1890 "The Principles of" this is considered a classic in the field

FJ 2001 In 1908 Hermann Ebbinghaus said this field "has a long past, but only a short history"

Frank Herbert 4x 25.0% stumper $900 avg DJ:4

DJ $800 2007 He wrote 5 sequels to "Dune", including "Dune Messiah" & "Children of Dune"

DJ $1,000 DD 2019 As well as playing in the "Dune"s, this sci-fi author penned "The White Plague", about a mad scientist's quest for revenge

DJ $800 1992 "Children of Dune" was his extremely successful sequel to "Dune" & "Dune Messiah"

the ohm 4x $650 avg J:2 DJ:2

J $300 1994 The Greek letter omega is used as the symbol for this unit of electrical resistance

J $500 1998 Ir"resistable" German physicist with a law about the flow of an electric current

DJ $1,000 1990 This unit of electrical resistance was named for a German physicist

Worth Knowing (31)

sound 3 pendulum 3 Kelvin 3 etymology 3 China 3 1 3 zenith 2 white light 2 toxicology 2 The Stepford Wives 2 the lens 2 the equator 2 superconductors 2 spectrum 2 Resistance 2 physics 2 Philip K. Dick 2 Mohs 2 melt 2 LSD 2 Lord Kelvin 2 lasers 2 Kinsey 2 Jules Verne 2 ice age 2 freezing point 2 Enamel 2 density 2 convex 2 conchology 2 complementary 2

Math / Physics

20 answers | 56 clues

Should-Know (4)

lightning 5x $580 avg J:3 DJ:2

DJ $200 1992 Pilots have reported seeing a rare form of this which strikes upward from a cloud rather than down

DJ $2,000 2016 Chinese scientists captured the first video & spectrum of the elusive ball type of this atmospheric phenomenon

J $200 1988 This discharge can be produced in snowstorms, sandstorms & volcanic clouds as well as thunderstorms

a lever 5x $240 avg J:2 DJ:3

J $100 1996 This rigid beam pivoted at a fulcrum is the simplest of simple machines

J $100 1987 One of the simplest machines, it's a rigid beam pivoted at a fulcrum

DJ $200 1988 From Old French "to raise", examples of this include a crowbar, tongs & a seesaw

direct current 5x $340 avg J:3 DJ:2

J $100 1988 A rectifier is an electrical device used to convert alternating current to this

DJ $800 1991 A galvanometer can tell you which way this is flowing

J $200 1995 A rectifier converts alternating current into this current

Marconi 4x 25.0% stumper $1,600 avg J:1 DJ:3

J $500 1987 For his work in radio, this Italian electrical engineer shared the 1909 Nobel Physics Prize

DJ $1,200 2024 "Thunderstruck" tells the interwoven stories of murderer Hawley Crippen & this wireless inventor

DJ $1,200 2004 For helping to develop "wireless telegraphy" he & Karl Braun shared the 1909 Nobel Prize in Physics

Worth Knowing (16)

wavelength 3 the jet stream 3 Lift 3 calculus 3 a prism 3 the red shift 2 the horizon 2 seismic waves 2 repel 2 Pascal 2 noise 2 Mach 2 H.G. Wells 2 geodesic 2 Doppler 2 colorblindness 2

Earth Science

16 answers | 50 clues

Should-Know (4)

seismology 7x 14.3% stumper $529 avg J:1 DJ:6

J $300 1986 While this study tries to predict when earthquakes will occur, it's still on shaky ground

DJ $600 1991 It's the science that deals with earthquakes & related phenomena

DJ $1,200 2021 Charles Richter taught this -ology at Caltech from 1937 to 1970

meteorology 7x $300 avg J:3 DJ:4

J $100 2000 Though it sounds like it deals with space matter, it's the study of weather

DJ $800 2013 This -ology practiced by a guy on the 6 o'clock news sounds like it's about bodies falling from space

J $200 2021 Atmospheric sciences include climatology & this, the study & forecasting of the weather

quartz 6x 33.3% stumper $1,100 avg DJ:6

DJ $400 2019 When exposed to electricity, this mineral vibrates at regular intervals, so it's used in wristwatches to keep accurate time

DJ $600 1992 Crystals of this mineral are used in wave transmitters of radio & TV sets

DJ $1,000 1992 Many of the gems sold as topaz are actually the citrine variety of this stone

magma 4x $700 avg J:1 DJ:3

DJ $400 2021 The mafic type of this 5-letter underground molten rock can reach more than 2,000 degrees Fahrenheit

DJ $800 2022 Igneous rocks are formed after this 5-letter type of molten rock cools

DJ $1,200 2015 The water in most hot springs is heated by this 5-letter substance

Worth Knowing (12)

chalk 3 a glacier 3 the troposphere 2 the lithosphere 2 Sound barrier 2 sedimentary 2 Plates 2 plate tectonics 2 obsidian 2 ice crystals 2 hurricanes 2 gemology 2

Medicine / Health

12 answers | 30 clues

Should-Know (2)

the kidney 5x 20.0% stumper $800 avg J:2 DJ:3

J $400 2016 A nephrectomy is the surgical removal of this organ

DJ $800 1992 An expert in nephrology would know a lot about this bodily organ

DJ $2,000 2018 When this organ is embryonic, specialized tubules empty into Wolffian ducts

X-rays 4x $350 avg J:2 DJ:2

J $100 1991 Barium sulfate is used in diagnosing gastrointestinal problems since it's opaque to these rays

DJ $600 1995 Wilhelm Roentgen announced the discovery of these rays in "Eine neue Art von Strahlen" in 1895

J $300 1996 Oh, ya doesn't hafta call 'em Roentgen rays, you can call 'em this

Worth Knowing (10)

Liver 3 valves 2 the brain 2 smallpox 2 salmonella 2 Pierre Curie 2 osteoporosis 2 isometric 2 hematology 2 geriatrics 2

Botany / Plants

4 answers | 9 clues

Worth Knowing (4)

fructose 3 spores 2 quinine 2 deciduous 2

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