Another week where you get a Women in Science rather than a weekly wrap up.
As a lot of you know I try to follow developments in the search for exoplanets and we have found quite a few now (1846 Confirmed / 4604 Candidates). While we know somethings about these planets there is plenty that we don’t know. The biggest question is do any of them support life. There are things we can look for that would support life. One team is trying to look at the light as it passes through the atmosphere of a planet transiting a star and using the absorption spectrum to see what is in the atmosphere.
NASA has formed a group call NExSS, currently made up of teams from 11 institutions, to answer some of these questions. They expect more teams and international teams to join in as things get rolling. NASA selected three people to lead this initiative each from a different NASA Center. Two of those people are Natalie Batalha and Dawn Gelino.
Natalie Batalha is a co-investigator on the Kepler Project.. She has written a number of papers but two of them relate to Kepler. The first talks about the criteria they used to select what spot of sky they were going to study. A number of factors went in to that including the ability for ground based telescope to look at that area of the sky to follow up; stars of a type that they predict would be more likely to have planets and to minimize clutter in the background.
The second paper narrowed the half a million stars in the field to 150,000 that they viewed. The first step was to catalogue all the stars in the field with ground based telescopes. They predicted which stars they would be able to detect a transiting star based on their equipment, the background clutter and the size of planet they could detect for that star.
Dawn Gelino created the website “The Habitable Zone Gallery” with a partner and wrote a paper on the math used to calculate the data. The site is wonderful and I have spent too much time looking at orbits. The movies are particularly cool as they give the temperature of the planet as they orbit.
She has written a number of papers to do with the habitable zones of planets. Habitable zone are basically defined as where water would be in liquid form. Clearly there are a lot of variables that enter into that. Some planets have orbits that only have parts of their orbit in the habitable zone. Our atmosphere affects the temperature of our planet so the composition of exoplanet atmospheres would also. The above image is one where the orbit crosses the habitable zone but it would be really cold in winter and boiling in summer. (173K to 397K / -100 c to 124 c)
Ok I am not going to get to a weekly update in this week so I am finishing up this “Women in Science” Post that has been sitting in my drafts for far too long.
Today’s post is on Dr Carolyn Porco who is a planetary scientist. Reading about her was like going down the rabbit hole. Every step I took involved taking another step so I could understand the first step. Every wonder led to another wonder that I need to read about. She has written 115 scientific papers so clearly I am only going to be scratching the surface. As always hopefully this is a starting point for your own rabbit hole of discovery. For the first link we will go with her biography on her website.
She was a member of the Voyager Imaging Team. As part of that team she described the ringlets and spokes in the rings of Saturn. She also showed how the two newly discovered moons of Uranus were shepherding the outer rings.
She also made a prediction along with another that certain features in the rings were cause by oscillations in Saturn and could be used as a seismograph. This led to a greater understanding of the structure of Saturn and other planets with rings. This prediction was shown to be correct 20 years latter with the Cassini / Huygens mission where she is in charge of the imaging team.
The Cassini / Huygens mission discovered seven new moons of Saturn and some new rings. One of the cool things is that they did some close flybys of some of the moons and dropped the Huygens probe down to the surface of Titan. One of these moons, Enceladus, is the most likely place for us to find life. It has been speculated that life there might predate life on Earth and even be the source.
In the TED video below she talks about the geysers on the south pole of Enceladus and that there is a liquid ocean under a frozen surface. She also talks about some of the carbon based molecules they detected as they flew the space craft through the geysers.
The next video is actually the TED talk that is mention above as having happened two years prior. In this one she is talking more about the discoveries on Titan and the landing of the probe Huygens.
Dr Sandra Faber is a Professor at the University of Califonia, Santa Cruz. She studies the formation of galaxies and the structure of the universe. Given that, I thought it would be a good idea to start with a short video on the size of the universe.
I started by reading the Wikipedia article on her. That led me off onto a journey though many pages. Some I had heard of but never actually read about or understood, the rest I had no idea about. She is the co-discoverer of the Faber-Jackson relationship that links the luminosity of elliptical galaxies to the velocity of the stars within. This leads to being able to estimate the distance to the galaxy.
She was also the head of the team that discovered the “Great Attractor”, a gravity anomaly. We now know that it is the central gravitational point for the Laniakea Supercluster that contains 100,000 galaxies.
The first video I found talks about the repairs to Hubble and her role in it. She diagnosed the problem and worked on coming up with a fix. They also talk about the look back effect of telescopes and Hubble specifically. The look back effect is that light takes time to travel and thus the light we see has spent years travelling. In the case of Hubble it can look at things where the light has been travelling 13 billion years and thus we are looking back at our early universe. I particularly liked the bit where she mentions liking that being a professor allows her to mentor others.
The next video is a TED talk that she did. She starts with a simulation of the formation of our galaxy. It is a chaotic formation but it is also beautiful. The coolest thing is the pictures of infant solar systems in the stellar nursery of Orion. It shows brand new starts surrounded by a dark disk of dust. She also shows us a picture of Earth taken from behind Saturn. I spotted the Earth right away but that was because I had seen the photo before and had a rough remembrance of where to look.
The growth problem that she talks about is a bit of a downer but something that we do need to deal with. Global warming is really the tip of that iceberg. We do have the technology to get past that one but there is a limit and we will hit it eventually unless we come up with solutions. In Larry Niven’s Ringworld the problem of growth is seen in a number of the races and dealt with in a variety of ways.
I have to say that I do believe in miracles however explaining my beliefs is its own post and probably will never be written.
The final article is an interview that she gave PBS. In it she explains how galaxies allowed the formation of planets. The gravity of the galaxy gathered up the heavier elements ejected from supernova. Without supernovas there would be no heavier elements and therefore no planets.
She also talks about spectrum and how they can use that to tell what elements a galaxy is made of. There is also a link to a website where you can try your hand at deciphering some spectrum.