Here’s A Great Example Of The Kinds Of Experiments Astronauts Perform On The International Space Station,

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

Ep. 12 Longitude - HD and the Void

The hardest part of determining longitude was figuring out how sailors could find their longitudinal coordinates at sea. There were a lot of methods proposed but adding a ship into the equation makes precision difficult. Learn about the Longitude ...

The hardest part of determining longitude was figuring out how sailors could find their longitudinal coordinates at sea. There were a lot of methods proposed but adding a ship into the equation makes precision difficult. Learn about the Longitude Act of 1714 and how, even though this podcast loves astronomy, the astronomical method might not always be the best option.

Below the cut are my sources, music credits, a timeline of the astronomers and engineers and clockmakers I mention, a vocab list, a really cool resource that lets you drag continents all over a flattened map of Earth to compare their sizes at different latitudes, and the transcript of this episode. Let me know 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 check out the podcast on iTunes, rate it or review it if you’d like, subscribe, and maybe tell your friends about it if you think they’d like to listen!

(My thoughts on the next episode were the Voyager golden records, space race history, the transit of Venus, or maybe something about the Moon landing. I’m loving Edmond Halley again these days, too. I’m prepping to interview a friend about her graduate-level research into the history of the universe and possibly dark matter, too. Let me know by the 20th and I’ll hopefully have the next podcast up on September 25th! If not then, I’ll push for October 2nd.)

Glossary

azimuth -  a section of the horizon measured between a fixed point and the vertical circle passing through the center of an object. See example in the link. 

equator - Earth’s zero line of latitude. It’s the place on Earth where the Sun is directly overhead at noon on the vernal and autumnal equinoxes.

kamal - an Arabic navigation tool consisting of a knotted string and a piece of wood. A navigator would tie a knot in the string and, by holding it in their teeth, sight the North Star along the top of the wooden piece and the horizon along the bottom. To return home, the navigator would sail north or south to bring Polaris to the altitude they had observed in their home port, then turn left or right and sail down the latitude, keeping Polaris at a constant angle. Over time, Arab navigators started tying knots at regular intervals of a fingerwidth, called an issbah, that’s about 1 degree and 36 minutes.

magnetosphere - an invisible barrier that surrounds a celestial objet. It is often generated by the movement of the liquid metal core of the object. Around a planet, it deflects high-energy, charged particles called cosmic rays that can either come from the Sun or, less often, from interstellar space.

prime meridian - Earth’s zero degree of longitude. In current maps and time zones, this invisible, imaginary line runs through London, England.

sextant - a device used to determine an observer’s location based on the observation of a known celestial object and a lot of calculation. It is still in use by sailors.

tropic of cancer - a line of latitude that marks where the Sun will be at noon on the summer solstice.

tropic of capricorn - a line of latitude that marks where the Sun will be at noon on the winter solstice.

Script/Transcript

Sources

Longitude at Sea via The Galileo Project at Rice University

Vitamin C necessity via University of Maryland Medical Center

Scurvy via NHS

Scurvy via the Encyclopedia Britannica online

An interactive map that shows how our current map distorts land masses by letting you compare different countries’ sizes.

Sobel, Dava. Longitude. Walker & Co.; New York, 1995.

“anyone living below the Equator would melt into deformity from the horrible heat” (3).

“It simply urged Parliament to welcome potential solutions from any field of science or art, put forth by individuals or groups of any nationality, and to reward success handsomely” (53).

Timeline

Claudius Ptolemy, Greek (100-170 CE)

Johannes Werner (in Latin, Ioannis Vernerus), German (1468-1522)

Tycho Brahe, Danish (1541-1601)

Galileo Galilei, Italian (1564-1642)

Giovanni Cassini (in French, Jean-Dominique Cassini), Italian/French (1625-1712)

Christiaan Huygens, Dutch (1629-1695)

Sir Isaac Newton, English (1642-1726/7)

Ole Rømer, Danish (1644-1710)

John Flamsteed, English (1646-1719)

Edmond Halley, English (1656-1742)

John Hadley, English (1682-1744)

John Harrison, English (1693-1776)

Thomas Godfrey, American (1704-1749)

John Bird, English (1709-1776)

Larcum Kendall, English (1719-1790)

James Cook, English (1728-1779)

Nevil Maskelyne, English (1732-1811)

John Arnold, English (1736-1799)

Thomas Earnshaw, English (1749-1829)

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

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

After 15 years, the Mars Opportunity rover's mission has ended

It's time to say goodbye to Opportunity. The Mars rover's team made its last attempt to contact Opportunity on Tuesday night, and it went unanswered. On Wednesday, NASA confirmed that the mission is over.

RIP, little buddy. 

Today I learned that the Curiosity sang itself ‘Happy Birthday’ on its year anniversary of being on Mars.

All alone.

Hundreds of thousands of miles from anyone or anything.

Guys I am depressed over robots now.

Five Famous Pulsars from the Past 50 Years

Early astronomers faced an obstacle: their technology. These great minds only had access to telescopes that revealed celestial bodies shining in visible light. Later, with the development of new detectors, scientists opened their eyes to other types of light like radio waves and X-rays. They realized cosmic objects look very different when viewed in these additional wavelengths. Pulsars — rapidly spinning stellar corpses that appear to pulse at us — are a perfect example.

The first pulsar was observed 50 years ago on August 6, 1967, using radio waves, but since then we have studied them in nearly all wavelengths of light, including X-rays and gamma rays.

Typical Pulsar

Most pulsars form when a star — between 8 and 20 times the mass of our sun — runs out of fuel and its core collapses into a super dense and compact object: a neutron star. 

These neutron stars are about the size of a city and can rotate slowly or quite quickly, spinning anywhere from once every few hours to hundreds of times per second. As they whirl, they emit beams of light that appear to blink at us from space.

First Pulsar

One day five decades ago, a graduate student at the University of Cambridge, England, named Jocelyn Bell was poring over the data from her radio telescope - 120 meters of paper recordings.

Image Credit: Sumit Sijher

She noticed some unusual markings, which she called “scruff,” indicating a mysterious object (simulated above) that flashed without fail every 1.33730 seconds. This was the very first pulsar discovered, known today as PSR B1919+21.

Best Known Pulsar

Before long, we realized pulsars were far more complicated than first meets the eye — they produce many kinds of light, not only radio waves. Take our galaxy’s Crab Nebula, just 6,500 light years away and somewhat of a local celebrity. It formed after a supernova explosion, which crushed the parent star’s core into a neutron star. 

The resulting pulsar, nestled inside the nebula that resulted from the supernova explosion, is among the most well-studied objects in our cosmos. It’s pictured above in X-ray light, but it shines across almost the entire electromagnetic spectrum, from radio waves to gamma rays.

Brightest Gamma-ray Pulsar

Speaking of gamma rays, in 2015 our Fermi Gamma-ray Space Telescope discovered the first pulsar beyond our own galaxy capable of producing such high-energy emissions. 

Located in the Tarantula Nebula 163,000 light-years away, PSR J0540-6919 gleams nearly 20 times brighter in gamma-rays than the pulsar embedded in the Crab Nebula.

Dual Personality Pulsar

No two pulsars are exactly alike, and in 2013 an especially fast-spinning one had an identity crisis. A fleet of orbiting X-ray telescopes, including our Swift and Chandra observatories, caught IGR J18245-2452 as it alternated between generating X-rays and radio waves. 

Scientists suspect these radical changes could be due to the rise and fall of gas streaming onto the pulsar from its companion star.

Transformer Pulsar

This just goes to show that pulsars are easily influenced by their surroundings. That same year, our Fermi Gamma Ray Space Telescope uncovered another pulsar, PSR J1023+0038, in the act of a major transformation — also under the influence of its nearby companion star. 

The radio beacon disappeared and the pulsar brightened fivefold in gamma rays, as if someone had flipped a switch to increase the energy of the system. 

NICER Mission

Our Neutron star Interior Composition Explorer (NICER) mission, launched this past June, will study pulsars like those above using X-ray measurements.

With NICER’s help, scientists will be able to gaze even deeper into the cores of these dense and mysterious entities.

For more information about NICER, visit https://www.nasa.gov/nicer

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Why Webb Needs to Chill

Our massive James Webb Space Telescope is currently being tested to make sure it can work perfectly at incredibly cold temperatures when it’s in deep space. 

How cold is it getting and why? Here’s the whole scoop…

Webb is a giant infrared space telescope that we are currently building. It was designed to see things that other telescopes, even the amazing Hubble Space Telescope, can’t see.  

Webb’s giant 6.5-meter diameter primary mirror is part of what gives it superior vision, and it’s coated in gold to optimize it for seeing infrared light.  

Why do we want to see infrared light?

Lots of stuff in space emits infrared light, so being able to observe it gives us another tool for understanding the universe. For example, sometimes dust obscures the light from objects we want to study – but if we can see the heat they are emitting, we can still “see” the objects to study them.

It’s like if you were to stick your arm inside a garbage bag. You might not be able to see your arm with your eyes – but if you had an infrared camera, it could see the heat of your arm right through the cooler plastic bag.

Credit: NASA/IPAC

With a powerful infrared space telescope, we can see stars and planets forming inside clouds of dust and gas.

We can also see the very first stars and galaxies that formed in the early universe. These objects are so far away that…well, we haven’t actually been able to see them yet. Also, their light has been shifted from visible light to infrared because the universe is expanding, and as the distances between the galaxies stretch, the light from them also stretches towards redder wavelengths. 

We call this phenomena  “redshift.”  This means that for us, these objects can be quite dim at visible wavelengths, but bright at infrared ones. With a powerful enough infrared telescope, we can see these never-before-seen objects.

We can also study the atmospheres of planets orbiting other stars. Many of the elements and molecules we want to study in planetary atmospheres have characteristic signatures in the infrared.

Because infrared light comes from objects that are warm, in order to detect the super faint heat signals of things that are really, really far away, the telescope itself has to be very cold. How cold does the telescope have to be? Webb’s operating temperature is under 50K (or -370F/-223 C). As a comparison, water freezes at 273K (or 32 F/0 C).

How do we keep the telescope that cold? 

Because there is no atmosphere in space, as long as you can keep something out of the Sun, it will get very cold. So Webb, as a whole, doesn’t need freezers or coolers - instead it has a giant sunshield that keeps it in the shade. (We do have one instrument on Webb that does have a cryocooler because it needs to operate at 7K.)

Also, we have to be careful that no nearby bright things can shine into the telescope – Webb is so sensitive to faint infrared light, that bright light could essentially blind it. The sunshield is able to protect the telescope from the light and heat of the Earth and Moon, as well as the Sun.  

Out at what we call the Second Lagrange point, where the telescope will orbit the Sun in line with the Earth, the sunshield is able to always block the light from bright objects like the Earth, Sun and Moon.

How do we make sure it all works in space? 

By lots of testing on the ground before we launch it. Every piece of the telescope was designed to work at the cold temperatures it will operate at in space and was tested in simulated space conditions. The mirrors were tested at cryogenic temperatures after every phase of their manufacturing process.

The instruments went through multiple cryogenic tests at our Goddard Space Flight Center in Maryland.

Once the telescope (instruments and optics) was assembled, it even underwent a full end-to-end test in our Johnson Space Center’s giant cryogenic chamber, to ensure the whole system will work perfectly in space.  

What’s next for Webb? 

It will move to Northrop Grumman where it will be mated to the sunshield, as well as the spacecraft bus, which provides support functions like electrical power, attitude control, thermal control, communications, data handling and propulsion to the spacecraft.

Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Ep. 3 Hubble Space Telescope - HD and the Void

Different kinds of telescopes and 19th-century photographic techniques demonstrate far more vividly than mere words can convey that taking photos of space is VERY hard, but the Hubble Space Telescope is doing it well at age 27! This episode talks ...

The last episode I posted went up on a very special birthday that I failed to acknowledge or, well, realize was even happening until I saw it on the Google homepage. So, to rectify this oversight, I’m talking about the history of cosmological photography and how we reached the high point of the Hubble Space Telescope, which turned 27 this past April 24th!

Below the cut is some elaboration on the episode itself, including my sources, music credits, a glossary, and a transcript (not an exact record of this episode, but it’s the loose, fairly conversational script I was working with). I mention a couple of books and authors in this episode so if you want to see that written down, those are there too (one of the authors is Chinese and listen, Chinese is at least as hard for me to pronounce as French. I did try though). I’m also on Twitter at @HDandtheVoid, though I keep forgetting I have it. Talk to me on there and maybe I won’t forget!

Let me know what you think of this episode, let me know what you think I should research next*, tell me a fun space fact… anything’s helpful at this point!

*(Move fast if you feel strongly about what I research next, though, cuz I have to get it done by May 22nd! My thoughts were henges because I didn’t get to them this week, probes and satellites, the planets, spectroscopy, or maybe black holes? Please hit me up by May 11th so I can start working on it!)

Glossary:

catadioptric/Cassegrain telescope - use lenses and mirrors in combination.

focal length - the distance between the lens and the image sensor of a camera when the subject of the photo is in focus. According to the Nikon website this is usually measured in millimeters, but I’ll take a wild guess and say it’s probably easier to measure it in feet on the Hubble Telescope because that thing is school bus-sized.

Lagrange points -  five points where three bodies can orbit each other, yet stay in the same position relative to each other in a stable configuration. L1-L3 are in line with each other, while L4 and L5 are at the points of equilateral triangles in the configuration. See an example specific to the James Webb Telescope in the link.

objective lens - the optical element that gathers light from the object being observed and focuses the light rays to produce an image at the focal point.

reflection telescope - reflects light rays off the concave surface of a parabolic mirror to get an image of a distant object. Higher contrast image, worse color quality.

refraction telescope - uses convex lenses to focus a far-off, dim image. Good color quality, poor contrast.

satellites - objects that move around a larger object. Can be man-made or natural. Geostationary satellites orbit west to east over the equator, moving in the same direction and at the same rate as Earth. Polar-orbiting satellites orbit north to south, which allows them to scan the Earth along longitude lines.

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. It orbited at L2, just like the James Webb Telescope will!

Script/Transcript (I do tend to embellish in the moment of recording so it’s not exact, but all the facts are there and I can’t know a fact and not talk about it so trust me, all you’re missing is probably another swear word or two)

Sources:

Facts about telescopes via the Naperville Astronomical Association

More facts about telescopes via Western Washington University

Earth’s atmosphere definition via the Encyclopedia Britannica Online

Correcting for atmospheric interference in astronomical imaging

Info on satellites for K-4th grade via NASA

Info on satellites for 5th-8th grade via NASA

What focal length means in photography via Nikon (the camera brand)

Hermann Oberth’s museum website

The history of NASA’s Orbiting Astronomical Observatories, which an older British gentleman seems to like enough to run a website about it

The history of OAO-3 aka Copernicus via NASA

Info on the Hubble Space Telescope for K-4th grade via NASA

Hubble-T’s 25th anniversary website, which I highly recommend. The timeline is a dream come true in terms of organization and brevity. It was last updated in December 2014, though, since that was when the Hubble was 25, so not a lot of new info there.

What the Hubble Space Telescope looks like, all its parts, and some of its history

What Hubble-T is looking at right now and why

The history of maintenance missions to the Hubble-T

Hubble: The Beginning, a 4-minute documentary video with a couple interviews, including Nancy Roman!

Hubble’s YouTube channel!!!!!!!!

Spitzer Space Telescope website

James Webb Space Telescope website

Hirshfeld, Alan. Starlight Detectives. Bellevue Library Press: NY, 2014.

Liu, Cixin. The Three-Body Problem. Trans. Ken Liu. Tor Books: NY, 2016.

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

Filler Music: ‘Supermassive Black Hole’ by Muse off their album Black Holes and Revelations

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

HELIACAL

[adjective]

pertaining to or occurring near the sun, especially applied to such risings and settings of a star as are most nearly coincident with those of the sun while yet visible.

Etymology: Late Latin hēliac(us) < Greek hēliakós.

[Luis Tamani - Luz Solar]

A ‘Ring of Fire’ solar eclipse is a rare phenomenon that occurs when the moon’s orbit is at its apogee: the part of its orbit farthest away from the Earth. Because the moon is so far away, it seems smaller than normal to the human eye. The result is that the moon doesn't entirely block out our view of the sun, but leaves an “annulus,” or ring of sunlight glowing around it. Hence the term  “annular” eclipse rather than a “total” eclipse.

Black Holes Are Real And Spectacular, And So Are Their Event Horizons

“Originally estimated to be slightly larger than its M87 counterpart, the black hole at the center of the Milky Way — known as Sagittarius A* — has not yet had its event horizon imaged. When you observe the Universe, you don’t always get what you expect; sometimes, you get what it gives you. Instead, it was M87’s black hole that came through first, which was a much brighter and a much cleaner signal.

What we’ve found is spectacular. Those dark pixels at the center of the image are actually the silhouette of the event horizon itself. The light that we observe comes from the accelerated, heated matter around it, which must emit electromagnetic radiation. Where the matter exists, it emits radio waves, and the dark circle we see is where the background radio waves are blocked by the event horizon itself.”

We have an event horizon, folks! It wasn’t the one at the center of our galaxy that came through first, but rather the one at the center of Messier 87: a black hole over 1,000 times more massive, but some 2,000 times farther away, than the one contained in the Milky Way. This is an ultramassive black hole that’s almost the size of the entire Solar System, and its event horizon is real.

Come get the full story on what we know, now that we have our image, about black holes in the aftermath of the Event Horizon Telescope!