HELIACAL

Ep. 14 Dark Matter Part 1 - HD and the Void

In preparation for a future interview with someone who knows much more about astroparticle physics and dark matter than I do, tune in this week for a quick-and-dirty breakdown of a theoretical particle that, if it exists, would clarify a couple of...

We’re getting theoretical here, and not just astronomy theory but particle theory. That’s right, it’s a dark matter podcast! Learn what some astronomers think it is and why other astronomers think there are better explanations for certain nutty galactic phenomena. Hear about MACHOs and WIMPs! Also learn what dark matter is too hot, too cold, too medium, or just right! 

Below the cut are my sources, music credits, a vocab list, a timeline of the scientists I mention, and the transcript of this episode. Tell me what you think I should research next by messaging me here, tweeting at me at @HDandtheVoid, or asking me to my face if you know me in real life. And please subscribe to the podcast on iTunes, rate it and maybe review it, and tell friends if you think they’d like to listen!

(There’s a lot of ever-evolving info about dark matter and I was not able to cover all of it in just one episode, so get excited to hear about dark matter’s friend, dark energy, on November 6th. My thoughts on the episode after that are still the Voyager golden records, space race history, the transit of Venus, the Moon landing, or Edmond Halley. Let me know what you think!)

Glossary

astroparticle physics - the interface between astrophysics and particle physics.

baryons - heaviest particles. Ex. Protons, neutrons. In astroparticle physics, electrons are included in baryonic matter.

bosons - particles that can exist in the same state at the same location at the same time. Ex. Photons, Higgs boson.

cosmic microwave background radiation - the electromagnetic radiation left over from the time of recombination in Big Bang cosmology.

dark matter - a theoretical mass made up of unknown particles that have not been created on Earth. It is used to explain why galaxy clusters have 10x the mass that their light output suggests they would have; why distant stars on the edges of spiral galaxies orbit at the same speed as stars near the center of the galaxy; and the accretion of gases that created galaxies at the beginning of the universe.

fermions - particles that cannot exist in the same state at the same location at the same time. Ex. Protons, neutrons, electrons, leptons.

gravitational lensing - when light from more distant sources passes near a massive star, galaxy, or galaxy cluster and the object’s gravity bends the light like a lens to provide a warped angle view of space.

leptons - lightest particles. Ex. Electrons, neutrinos, tau particles, muons.

MACHO - acronym for MAssive Compact Halo Object. Made of baryonic matter, these objects are a theoretical explanation that takes the place of dark matter and include neutron stars, black holes, or brown dwarfs.

mesons - medium-weight particles. Ex. Pions, kaons.

Planck satellite - a spacecraft that operated from 2009 to 2012. It measured the dark matter content of the universe by looking at the cosmic microwave background radiation and seeing how dark matter clumped and drew the regular matter together to form galaxies.

WIMP - acronym for Weakly Interacting Massive Particle. Theoretical particles that can pass through ordinary matter without affecting it.

Wilkinson Microwave Anisotropy Probe - a spacecraft operating from 2001 to 2010 which measured temperature differences in the cosmic microwave background radiation leftover from the Big Bang.

Transcript

Sources

Fritz Zwicky via the Swedish Morphological Society

Fritz Zwicky via the American Museum of Natural History

Zwicky: “Astronomers are spherical bastards. No matter how you look at them they are just bastards“

Vera Rubin via the American Museum of Natural History

Vera Rubin via Astronomy Magazine

Morton Roberts’ 2007 article on dark matter via Harvard

Particle classifications via PhysicsNet.co.uk

Leptons via Georgia State University, copyright 2001 and all written by Carl “Rod” Nave, who has a teaching award named after him at GSU. Go Rod!

Fermions and bosons via The Particle Adventure

MOND theory by Mordehai Milgrom, published in Scientific American Aug. 2002

Newton’s Second Law of Motion via NASA

MACHOs and WIMPs via NASA

MACHOs and WIMPs via the Encyclopedia of Astronomy and Astrophysics

Bertone, Gianfranco. Behind the Scenes of the Universe: From the Higgs to Dark Matter. Oxford U P: Oxford, 2013.

Tucker, Wallace H. Chandra’s Cosmos: Dark Matter, Black Holes, and Other Wonders Revealed by NASA’s Premier X-Ray Observatory. Smithsonian Books: Washington, D.C, 2017.

“a mysterious force that causes the observed accelerating expansion of the universe” (3).

“sterile neutrinos, axions, asymmetric dark matter, mirror dark matters, and extradimensional dark matter” (23).

“the concentration of dark matter is leveling off, rather than peaking sharply, in the central regions of this cluster” (31).

Timeline

Albert Einstein, German/Austrian (1879-1955)

Edwin Hubble, American (1889-1953)

Walter Baade, German (1893-1960)

Fritz Zwicky, Swiss (1898-1974)

Enrico Fermi, Italian (1901-1954)

Morton S. Roberts, American (1926- )

Vera Rubin, American (1928-2016)

Peter Higgs, English (1929- )

Kent Ford, American (1931- )

Mordehai Milgrom, Israeli (1946- )

Romeel Dave

Rachel Somerville

Intro Music: ‘Better Times Will Come’ by No Luck Club off their album Prosperity

Filler Music: ‘Darkmatter’ by Andrew Bird off his album Fingerlings 3

Outro Music: ‘Fields of Russia’ by Mutefish off their album On Draught

Ongoing Space Science Seeks to Keep Astronauts Healthy

ISS - Expedition 50 Mission patch. March 10, 2017 NASA is preparing for longer human journeys deeper into space and is exploring how to keep astronauts healthy and productive. The Expedition 50 crew members today studied space nutrition, measured their bodies and checked their eyes to learn how to adapt to living in space. The space residents also unloaded a cargo ship, worked on the Tranquility module and practiced an emergency simulation. The ongoing Energy experiment that ESA astronaut Thomas Pesquet collected urine samples for today seeks to define the energy requirements necessary to keep an astronaut successful during a space mission. Pesquet also joined NASA astronaut Peggy Whitson for body measurements to learn how microgravity affects body shape and impacts crew suit sizing. Commander Shane Kimbrough checked his eyes today with Whitson’s help and support from experts on the ground.

Image above: Astronaut Shane Kimbrough and Thomas Pesquet were pictured inside the cupola just after the SpaceX Dragon was captured Feb. 23, 2017. Image Credit: NASA. Kimbrough worked throughout the day before his eye checks and configured the Tranquility module for upcoming electronics and communications work. Cosmonaut Oleg Novitskiy continued unloading gear from the newly-arrived Progress 66 cargo ship. At the end of the day, Novitskiy joined Whitson and Pesquet for an emergency simulation with inputs from control centers in Houston and Moscow. Related links: Energy experiment: https://www.nasa.gov/mission_pages/station/research/experiments/397.html Body measurements: https://www.nasa.gov/mission_pages/station/research/experiments/1070.html Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html Image (mentioned), Text, Credits: NASA/Mark Garcia. Best regards, Orbiter.ch Full article

The Galactic Starburst Region NGC 3603

js

sun depicted as a divinity petroglyph on the plateau Yagour (High Atlas mountains), Morocco.. 6000 to 8000 BC

Planets i learned about via youtube while procrastinating my english essay

Planet 55 Cancri e is basically a giant diamond. like the planet is a diamond. and it would be worth $26.9 nonillion

Planet Gliese 436 b is an ice planet that is constantly on fire do to its close proximity to its parent star. the ice doesn’t melt bc the planet’s gravity is so strong it physically prevents the ice from melting

Planet HD 189733b rains sideways glass…. constantly

Planet J1407-B has planetary rings that are 200x the size of saturn. if saturn’s ring were as big as J1407-B’s we’d be able to see them with our naked eye from earth AND they would dominate our sky and look larger than a full moon

Planet Wasp-12b rotates so close to its parent star that its slowly being consumed by the it

Planet Gliese 581c is one of the candidates for a planet that can support life however it orbits a tiny dwarf star and is tidally locked so one side is constantly subject to immense sunlight while the other is constantly in darkness. there’s a small area of the planet however, that is just the right temp to support life. u just can’t step out of said area. the skies are red and the plants would have be a black color instead of a green bc they would use infrared light for photosynthesis. (a message was actually sent to the planet in 2008 in hopes that there’s life on the planet but the message wont reach the planet until 2029).

Planet GJ 1214b is a water planet nicknamed “water world” is has no land at all and the water is so deep it goes down miles all the way to the planet’s core.

Planet Wasp-17b is the largest planet discovered thus far. its so large its existence contradicts our understanding of how planets are formed. and it has a retrograde orbit, so it orbits in the opposite direction of its parent star.

Planet HD 188753 has 3 suns you should have triple shadows and there would be almost daily eclipses. and no matter which direction u face on the planet u would always see a sunset

Planet HD106906b is the loneliest planet discovered thus far. its known as “super jupiter” bc its 11x bigger than jupiter. it orbits its parent star at a distance of 60 billion miles (which is v strange) hence why its the loneliest planet.

Planet Tres 2b is the darkest planet known. it reflects less than 1% of light (it reflects less light than coal and black acrylic paint). the tiny part of the planet that does reflect light is red making the planet glow a dim red.

This has been going on since 1995! There are so many pictures! I gotta check these out but it will take hours. Maybe treat myself to like ten a day? It’s a better way to wake up than checking Facebook right now, I like this plan.

Ep. 28 Tidal Forces - HD and the Void

Tidal forces are not only the cause of ocean tides, but affect how satellites orbit objects in space, and they can even tear some objects apart under their extreme stresses. Learn about types of tides on Earth and in our solar system.

This episode’s been a long time coming because the topic’s come up before. I originally conceived of this podcast as a way for me to learn about space things I’d always taken for granted, and truly, there is nothing closer to home that I’ve just agreed to believe than the statement that the tides are affected by the Moon. What? How? Why? All these questions and some I didn’t even realize I had will be answered in this episode on tidal forces!

Below the cut are my standard glossary, transcript, sources, and music credits. Send me any topic suggestions via Tumblr message (you don’t need an account for it!). You can also tweet at me on Twitter at @HDandtheVoid, or you can ask me to my face if you know me. Subscribe on iTunes to get the new episodes of my maybe now monthly-updated podcast (we’ll see how the weeks unfold), and please please please rate and review it. Go ahead and tell friends if you think they’d like to hear it, too!

(My thoughts on the next episode are Stephen Hawking and his theories, or famous comets. The next episode will go up in September—ideally, September 10th!)

Glossary

barycenter - the common center of mass between two objects that allows them to orbit.

Roche limit - the distance in which a celestial body will disintegrate because of a second celestial body's tidal forces exceeding the first body's gravitational self-attraction, or the force that’s holding it together. Within the Roche limit, orbiting material disperses and forms rings, like how Saturn’s rings are within the Roche zone; outside the limit, material tends to coalesce.

spaghettification - when extreme tidal forces pull an object apart in space.

tidal force - an apparent force (sometimes also called the differential force) that stretches a body towards another, more gravitationally-strong body’s center of mass. This can cause such diverse phenomena as tides, tidal locking, breaking celestial bodies apart to form ring systems within a Roche limit, and in extreme cases, spaghettification. It arises because the gravitational force exerted on one body by another is not constant across its parts: the nearest side is attracted more strongly than the farthest side.

Types of ocean tides:

diurnal tide - a daily tidal cycle with only one high and low tide each lunar day, and a period of a little over 24 hours.

meteorological tide - a tidal change due to weather patterns. Wind, or unusually high or low barometric pressure causes variations between the actual sea level and its predicted height.

mixed tide - a daily tidal cycle with two high and low tides that differ in their peaks. This difference in height between successive high or low tides is called the diurnal inequality. They have a period of 12 hours and 25 minutes.

neap tide - a type of bi-monthly tidal cycle that occurs when the Sun, Earth, and Moon are positioned at a 90-degree angle, so the tidal forces of the Sun are acting against the tidal forces of the Moon. During a neap tide, the difference between high tide and low tide is the least extreme.

semidiurnal tide - a daily tidal cycle with two nearly equal high tides and low tides every lunar day. They have a period of 12 hours and 25 minutes.

spring tide - a type of bi-monthly tidal cycle that occurs when the Sun, Earth, and Moon line up so that the gravitational forces of Sun and Moon are working together to form a large tidal bulge. During a spring tide, the difference between high tide and low tide is at its maximum.

tidal locking - when long-term interaction between two co-orbiting astronomical bodies causes at least one of the bodies to rotate in such a way that one face of the body is always pointed at the body it’s orbiting. This is also called gravitational locking or captured rotation. An example is that the same side of the Moon always faces the Earth, and its synchronous rotation means that it takes just as long to rotate around its own axis as it does to revolve around the Earth.

Script/Transcript

Sources

Tidal Cycles in Tides Explained via beltoforian.de

“a tide is a distortion in the shape of one body induced by the gravitational pull of another nearby object.”

Meteorological effects on tides via the New Zealand Government website

Tides and Water Levels via the National Oceanic and Atmospheric Administration (NOAA)

Tides by R. Nave, my dude, my guy, my friend and yours, of Georgia State University

The Tidal Force by Neil deGrasse Tyson via Hayden Planetarium (Nov 1995)

“A mild increase in distance between two objects can make a large difference in the strength of the tidal force. For example, if the Moon were just twice its current distance from us, then its tidal force on Earth would decrease by a factor of eight. At its current average distance of 240,000 miles from Earth, the Moon manages to create sizable atmospheric, oceanic, and crustal tides by attracting the part of Earth nearest the Moon more strongly than the part of Earth that is farthest. (The Sun is so far away that in spite of its generally strong gravity, its tidal force on Earth amounts to less than half that of the Moon.) The oceans respond most visibly in being stretched toward the direction of the Moon.” 

“When Earth's rotation slows down until it exactly matches the orbital period of the Moon, then Earth will no longer be rotating within its oceanic tidal bulge and the Earth-Moon system will have achieved a double tidal lock. In what sounds like an undiscovered wrestling hold, double tidal locks are energetically favorable (like a ball coming to rest at the bottom of a hill), and are thus common in the universe.”

Forget “Earth-Like”—We’ll First Find Aliens on Eyeball Planets via Nautilus (Feb 2015)

High Tide on Io! via NASA (Mar 2012)

Tidal forces and spaghettification via NASA handout

Spaghettification via Cosmic Funnies

Single atoms feel tidal force via Physics World (May 2017)

Robbins, Tom. Still Life with Woodpecker. Bantam Books: New York, 1980.

“Being four times larger than the moon, the earth appeared to dominate. Caught in the earth’s gravitational web, the moon moved around the earth and could never get away. Yet, as any half-awake materialist well knows, that which you hold holds you.”

Sobel, Dava. The Planets. Viking: NY, 2005.

Intro Music: ‘Better Times Will Come’ by No Luck Club off their album Prosperity

Background Music: ‘Sad Business’ by Patients aka Ben Cooper, who primarily releases music as Radical Face but also has at least three other bands or band names he’s working with/has released music as.

Filler Music: ‘It’s Getting Boring by the Sea’ by Blood Red Shoes off their album Box of Secrets

Outro Music: ‘Fields of Russia’ by Mutefish off their album On Draught

New Horizons Flyover of Pluto

Using actual New Horizons data and digital elevation models of Pluto and its largest moon Charon, mission scientists have created flyover movies that offer spectacular new perspectives of the many unusual features that were discovered and which have reshaped our views of the Pluto system – from a vantage point even closer than the spacecraft itself. This dramatic Pluto flyover begins over the highlands to the southwest of the great expanse of nitrogen ice plain informally named Sputnik Planitia. The viewer first passes over the western margin of Sputnik, where it borders the dark, cratered terrain of Cthulhu Macula, with the blocky mountain ranges located within the plains seen on the right. The tour moves north past the rugged and fractured highlands of Voyager Terra and then turns southward over Pioneer Terra – which exhibits deep and wide pits – before concluding over the bladed terrain of Tartarus Dorsa in the far east of the encounter hemisphere. Digital mapping and rendering were performed by Paul Schenk and John Blackwell of the Lunar and Planetary Institute in Houston.

What is an upcoming project/mission you're most excited for?

It is likely that I’ll be assigned a mission to the International Space Station (ISS) within the next few years.  We’ve had a continuous presence on the Space Station for 17 years now, along with our international partners (Russian Space Agency, European Space Agency, Japanese Space Agency, and Canadian Space Agency).  Missions on the ISS typically last 6 months.  I’m incredibly excited to contribute to the impressive array of scientific experiments that we are conducting every day on ISS (I am a scientist after all!), and very much look forward to the potential of going for a spacewalk and gaining that perspective of gazing down on the fragile blue ball that is our home from above.  Beyond that, being part of test missions on the Orion spacecraft (currently under construction at NASA!) would be an extraordinary opportunity.  The current NASA plan is to send astronauts in Orion in a mission that will go 40,000 miles beyond the Moon in the early 2020s, reaching a distance further than that ever travelled by humans.  I’d certainly be game for that! 

Ep. 22 African-American Astrophiles - HD and the Void

As Black History Month 2018 wraps up, learn about some of the African-American men and women who have contributed to space research and exploration! 7 astronomers and 9 astronauts shine in this episode, which spans from the 1700s to modern-day folks.

February is Black History Month, and it’s been the perfect excuse to research all of the African-American people who have contributed to space research and exploration! I talk about seven astronomers and nine astronauts who have delved into outer space because it was just so dang amazing, nothing could stop them from learning about it; astrophiles, if you will. Space-lovers.

Below the cut, I have the transcript, sources, music credits, and timeline of people I talked about! Maybe you have something you want to hear me talk about that’s related to space. I’m kind of set for topics for the next few months but I’ll take suggestions here or you can tweet at me on Twitter at @HDandtheVoid, or you can ask me to my face if you know me. Please subscribe on iTunes, rate my humble podcast and maybe review it, and tell friends if you think they’d like to hear it!

(My thoughts on the next episode are the SOFIA observatory, Chuck Yaeger, the transit of Venus, or quasars and blasars. The next episode will go up March 19th, unfortunately; I have a work retreat the day I’d usually post and I don’t trust the wifi out there. See you then!)

Script/Transcript

Timeline

Benjamin Banneker, American (1731-1806)

Dorothy Vaughan, American (1910-2008)

Katherine Johnson, American (1918- )

Mary Jackson, American (1921-2005)

Ed Dwight, American (1933- )

Robert Henry Lawrence, American (1935-1967)

Doctor Arthur Bertram Cuthbert Walker II, American (1936-2001)

Frederick Gregory, American (1941- )

Guion "Guy" Bluford, American (1942- )

Doctor Ronald E. McNair, American (1950-1986)

Ilan Ramon, Israeli, American (1954-2003)

Doctor Bernard Harris, Jr., American (1956- )

Doctor Mae Jemison, American (1956- )

Neil DeGrasse Tyson, American (1958- )

Michael P. Anderson, American (1959-2003)

Leland Melvin, American (1964- )

Doctor Beth A. Brown, American (1969-2008)

Sources

African Americans in Astronomy and Space via ThoughtCo (Mar 2017)

Benjamin Banneker via Encyclopedia Britannica

Benjamin Banneker via PBS

Benjamin Banneker via America’s Library

Benjamin Banneker via Brookhaven National Laboratory

Hidden Figures (2016)

Katherine Johnson via NASA

Mary Jackson via NASA

Dorothy Vaughan via NASA

Doctor Arthur Bertram Cuthbert Walker II via Encyclopedia Britannica

Doctor Arthur Bertram Cuthbert Walker II obituary via the American Astronomical Society

Ed Dwight via The History Makers

Robert Henry Lawrence via Black Past

Robert Henry Lawrence via PBS

Robert Henry Lawrence via Hill Air Force Base

Guion "Guy" Bluford via Space.com (Feb 2017)

Guion Bluford: “I mean, I laughed and giggled all the way up. It was such a fun ride.” 

Guion "Guy" Bluford via NASA

Guion "Guy" Bluford via Encyclopedia Britannica

Doctor Ronald E. McNair via NASA

Doctor Ronald E. McNair via Black Past

Doctor Ronald E. McNair via New Jersey Institute of Technology

Frederick “Fred” Gregory via NASA

Frederick “Fred” Gregory via Black Past

The Harris Foundation website

“empower individuals, in particular minorities and others who are economically and/or socially disadvantaged, to recognize their potential and pursue their dreams.”

Doctor Mae Jemison via NASA

Doctor Mae Jemison via NASA

Doctor Mae Jemison via the U.S. National Library of Medicine

Mae Jemison: “I followed the Gemini, the Mercury, and the Apollo programs, I had books about them and I always assumed I would go into space. Not necessarily as an astronaut; I thought because we were on the moon when I was 11 or 12 years old, that we would be going to Mars—I'd be going to work on Mars as a scientist. And that's despite the fact that there were no women, and it was all white males—and in fact, I thought that was one of the dumbest things in the world, because I used to always worry, believe it or not as a little girl, I was like: What would aliens think of humans? You know, these are the only humans?”

Michael P. Anderson via NASA

Michael P. Anderson via Black Past

Ilan Ramon via NASA

Leland Melvin via Space.com (Nov 2017)

Leland Melvin as Makers Men via Space.com (May 2017)

Leland Melvin via NASA

Leland Melvin via Pioneer Works

Doctor Beth A. Brown via the American Physical Society

Doctor Beth A. Brown via the American Astronomical Society

Doctor Beth A. Brown via NASA

Neil DeGrasse Tyson via Hayden Planetarium

Neil DeGrasse Tyson via the New Yorker

StarTalk Radio via Apple Podcasts

Intro Music: ‘Better Times Will Come’ by No Luck Club off their album Prosperity

Filler Music: ‘Dorothy Dandridge Eyes (feat. Esperanza Spalding)’ by Janelle Monáe off her album The Electric Lady.

Outro Music: ‘Fields of Russia’ by Mutefish off their album On Draught