Tag Archives: NASA

Has Science Been Fair to the Fair Sex?

I know Women’s History Month is almost over, but the points raised in this post are still very valid.

The film, “Hidden Figures” has been in the news quite a bit recently.  It is a dramatization of the real-life story of Katherine Johnson, Dorothy Vaughan, and Mary Jackson, three African-American women who did heavy-duty mathematical calculations at NASA in the 1960s. Even though computers did exist in those days, they were the size of large refrigerators and had far less computing power than even the lowly Commodore VIC-20 (a nearly 40-year old personal computer).  Thus, humans were still needed to do the mathematical work that the early manned space missions required.

However, those women had several things going against them.  One was that they were women.  Another was that they were African-American.  On top of that, NASA facilities were mostly in the South.  In the case of Kennedy Space Center (though it wasn’t called that until after the assassination of John F. Kennedy), it was due to considerations of orbital mechanics.  As for the other NASA centers, it was to placate influential politicians.  As a result, segregation was in full force at the time.  Johnson and her team worked in a separate office, had a separate lunch area, and were treated as second class people by most at NASA.  However, John Glenn judged them by their work and treated them well.  In fact, he demanded that Johnson personally handle the computations for his orbital flight.

This got me to look back at other women in the history of science.  It turns out that the snubs and treatment that Johnson and her team got were not new.

One famous example was Caroline Herschel.  Due to her growth being stunted in childhood by disease, she was quite short.  On top of that, her parents told her that she would amount to nothing.  However, she helped out her brother, William Herschel, the greatest observational astronomer of his era.  Eventually, she learned enough that she became an observer herself, discovering several deep sky objects as well as a few comets.  Despite her superb training, her contributions were largely forgotten.  Even among modern astronomers, she is little known.

Another case was Maria Mitchell.  She was born into a Quaker family and, since the Quakers believed in equal education, she received far better education than most women of that era.  Mitchell developed an interest in astronomy early in life and became one of America’s first professional astronomers and the first female one.  During the 1840s, the King of Denmark gave an annual award to people who discovered comets.  In 1841, Mitchell discovered a comet and was up for the award.  However, there were astronomers who felt that she did not deserve to get it and raised quite a furor over the matter.  Finally, the Danish authorities intervened and Mitchell got her medal.

Jumping forward to the early 20th century, Harvard Observatory hired a number of women to do mathematical work and measurements of images on glass photographic plates.  Much like Katherine Johnson and her team, these women were referred to as “computers”.  Unlike Johnson, these computers earned sweatshop wages.  But, it was far safer than most of the work women got in that era, working in dangerous mills as well as garment manufacturing (anybody recall the Triangle Shirtwaist fire?). One of these women, Henrietta Swan Leavitt was assigned the task of studying stars on glass photographic plates.  Her job was to locate stars in the Magellanic Clouds that varied in brightness.  Doing so, she discovered that one class of stars (what we call Cepheid variables) had a brightness that was proportional to their period (cycle of variability).  This became known as the period-luminosity relationship and laid the foundation for finding distances to nearby galaxies.  Since she was just a lowly computer, her bosses took credit for the discovery.  But the truth eventually won out and the story is well known in astronomical circles today.

I could go on and on with other examples, such as the career of Lise Meitner, who had to contend with sexism as well as the rise of Nazi Germany, the story of how Watson and Crick might have “borrowed” information from a female colleague to aid their discovery of the structure of DNA, but here is a case of how a woman scientist made a discovery, only to have it stolen from her.

In 1968, Jocelyn Bell was working at Cambridge when she made an odd discovery.  When the radio telescope was pointed at a spot in the constellation of Vulpecula, a rapid pulsing signal was detected.  The pulses were very precise, enough that some people thought it was an alien radio beacon.  This idea soon fell by the wayside and it was learned that the object responsible was a pulsar, a rapidly rotating neutron star that emitted radio energy like the beam of a lighthouse.  Once the significance of this became apparent, Anthony Hewish and Martin Ryle, Bell’s bosses, took credit for the discovery.  Though she did win a Michelson Award (along with Anthony Hewish) in 1973, she was totally ignored when the Nobel prize in physics was handed out in 1974 with Hewish and Ryle getting the prize.  Despite protests from other prominent physicists, Bell was denied Nobel recognition.  While the history books got things right in the end, it was too late for Bell to get the prize.  But she was made a Dame by Queen Elizabeth II some years later.

Sometimes, the side of good wins.  In 1979, Voyager 1 passed through by Jupiter and made many observations.  About three days after closest approach, navigation engineers were poring over the images sent back.  This was to refine the position of the spacecraft as well as the orbits of the Galilean moons.  One of those people, a woman by the name of Linda Morabito, noticed something odd in an image of Io.  It appeared that there was a limb of another moon peeking out from behind Io. Instead of jumping to conclusions, Morabito enhanced the image and, probably echoing the thought of Han Solo when he first saw the Death Star, found that was no moon.

converted PNM file

The first image of Io’s volcanism

It was actually the plume from a volcanic eruption on Io, the first display of active volcanism outside Earth.  Morabito was determined to get credit for this find and pushed her case.  Finally, with the mainstream media on her side, she was credited with the find, securing her place in scientific history.

These days, Morabito is involved in advocating for science.  In additon to her personal website, she also maintains a Facebook group, Linda Morabito’s Space Place where she offers commentary on various scientific issues.

So, as Women’s History Month draws to a close, remember the contributions women have made in science and let’s hope for the day when science gives credit where it is due without regard to whether it was a man or a woman who made the discovery.

Orion Oversold?

December 4th is the date set for the first test flight of NASA’s new Orion capsule.  It will be launched into Earth orbit using a Delta IV rocket at about 7:05 AM.  Then, Orion will circle the Earth twice, conduct some test maneuvers, then enter the atmosphere at about 80% of the velocity the capsule would have if it was returning from the Moon.  If the reentry systems work properly, Orion should splash down in the Pacific off the coast of San Diego, California before noon.  Unless it lands like the capsule in “Gravity”, Orion will be bobbing at the surface and picked up by a waiting ship.

NASA has been loudly promoting Orion, claiming that it is the vehicle that will take American astronauts beyond low Earth orbit and to destinations such as the Moon and Mars.  Much ink and many pixels have been used to promote Orion as a truly advanced spacecraft.  But let’s see it for what it is.

I dimly recall back in the early 1970’s there was a proposal to build a larger version of the Apollo-era command module.  The plans were all drawn up for it, then it was decided that there was no need for it.  Orion looks like the resurrection of this project.  Of course, Orion does have some updated technology, such as new heat shield material, far superior computers, nicely decorated interior, and touchscreen panels (like the controls you would find on “Star Trek: The Next Generation” or on an Asgard ship from the “Stargate” franchise, if you prefer).  But don’t be fooled, it is still based on your father’s (or grandfather’s depending on your age) Apollo command module.

Actually, there is something about Orion that is actually inferior to the original Apollo-era vehicle.  The Orion will use a service module that is based on the ESA’s (European Space Agency) Automated Transfer Vehicle (ATV) that has been used to send supplies up to the ISS.  This ATV-derived service module will use solar panels instead of fuel cells to generate electrical power and will certainly have far less powerful engines than the original Apollo-era service module did.

Then, there was a statement made about the Orion by a Russian commentator who pointed out that, for a vessel that is supposed to house a crew for up to three weeks or so, it lacked certain amenities.  While on a short trip to the Moon, that might not be a big deal since the original Apollo astronauts didn’t complain about the lack of a convenience, it could pose a problem for longer trips.

What bothers me is how NASA keeps pushing the idea that Orion will take astronauts to Mars.  It is simply way too small for the job (unless someone manages to develop the technology used to create the sub-light propulsion systems of mainstream science fiction programs).  Even Robert Zubrin (creator of the Mars Direct concept of a reasonably priced program of Mars exploration) and his colleagues and the folks at Mars Direct have put more thought into designing a spacecraft to take people to Mars.

Why has NASA gone so far overboard in promoting Orion?  Probably because that it is about the only idea they have left for manned spaceflight (besides the Space Launch System – SLS – heavy rocket).

Hopefully the test flight of Orion will go well and not wind up exploding, running out of power,  sinking on splashdown, or anything like that.  But do you think that Orion’s “Back to the Future” approach is the way to go or do you think it’s another one of NASA’s ideas that will fall well short of the mark?

What is the Real Cost of Saving Kepler?

Kepler K2 Mission Diagram

Diagram of Kepler’s K2 Mission

In March of 2009, the Kepler mission was launched.  It was placed in an Earth-trailing orbit around the Sun and observed a patch of sky located in the Milky Way near the constellation of Cygnus to look at thousands of stars to detect any dimming that was caused by a planet passing in front of a star.  This mission was by any criterion a great success and racked up an impressive number of discoveries, including the first rocky planets in the habitable zone of a star.

However, in April of 2013, one of the spacecraft’s reaction wheels (powered gyroscopes used to control the pointing of the vehicle) failed.  One had failed earlier, but there were still enough wheels for the mission to continue.  This time was different.  Kepler was placed into a safe mode which allowed it to communicate to Earth.  For the next three months, various strategies were tried to see if the reaction wheel that failed earlier could be restarted.  It was restarted but did not function well.

Then, some on the team had a stroke of brilliance.  After doing the complicated math and computer simulations, they came up with a way to save the mission by using the pressure of solar radiation (a major cause of instability to Kepler) as a means to help keep the spacecraft stable.  NASA liked the idea, known as “K2” (no connection to the extremely dangerous Himalayan mountain of the same designation) and depicted in the above diagram.  So, Kepler was saved, but at what cost?

In terms of dollars and cents, it was a great bargain.  However, when it came to Kepler’s capabilities, it turns out to be an almost Faustian deal.

The great strength of the original Kepler mission was that it kept one well-known section of sky under continuous surveillance.  That way, Kepler would not miss anything that took place.  As a result, Kepler discovered planets of longer periods and was able to observe the three transits required to confirm the discoveries.  The success of this strategy can be seen in the large number of planet discoveries from the mission.

Due to the use of solar radiation pressure as stabilization, Kepler has to be pointed at the ecliptic plane (the plane where the planets of the solar system tend orbit).  That doesn’t sound so bad, but since the Sun appears in the ecliptic plane, Kepler has to move to observe another field about every 83 days so the Sun doesn’t shine into the instrument and burn out the detectors.  Factoring in the time it would take to adjust Kepler each time it moved to one of the eight fields, that yields less than 83 days per field.  So, the concept of continuous surveillance goes right out the window.

Since a “year” for Kepler in its solar orbit is 379 days and only about four and a half fields can be observed in one Kepler “year”, that means quite a bit of time will pass before it returns to a field for further observation.  A lot can happen in that time and a many potential planets will be missed.  Mission scientists naturally downplay this and claim that the increased number of viewing locations will make up for it.  True, there will be some discoveries made from the K2 mission, but they won’t be anywhere near as numerous due to the spotty nature of the observations.  If you are a fan of extrasolar planets, you better get used to most of the new discoveries being hot Jupiters, hot Neptunes, and lava worlds, rather than the more interesting habitable zone planets, because the short duration of observations in each field will favor the planets with really short orbital periods, even with the new policy of requiring only two repeat transits to confirm a planet instead of three.

And this approach of observing lots of area for shorter intervals appears to be the wave of the future in searching for extrasolar planets from space.  If you like the K2 mission, you’ll love the followup mission to Kepler called TESS (Transiting Exoplanet Survey Satellite) which will survey most of the sky while in an eccentric Earth orbit with little time devoted to each field.

You can read the full gory details about K2 here.  Is the new strategy of observing more area in less time worth it for extrasolar planets or should there be a return to more time in less area in the future?