Posts Tagged ‘astronomy’

Speech on Why Exogeology ROCKS!

Posted by Zoe on 28th July 2012 in Main Page

You’ve heard that exogeology rocks, but just what is exogeology? Why does it rock?

I recently gave a speech on just that: Why Exogeology ROCKS!

Transit of Venus

Posted by Petra on 4th June 2012 in Main Page, Petra's Blog

Image credit: NASA

Tomorrow, you’ll have a once-in-a-lifetime opportunity to actually see a planet cross over a star. Venus transits our sun for the last time in over a century at 22:09 UTC, June 5th, so find a way to watch.

Why is this so special?

If you have any astronomer friends, they’ve probably been blabbering on for months about orbital periods this, first contact that. Why won’t we shut up? Because this is literally once in a lifetime, and it’s kinda cool.

Venus, the next planet inward, will cross directly over the visible disc of the sun. It will appear as a tiny black dot, about one arcminute, covering a minuscule fraction of the disk. This isn’t a lot, but it’s enough to see with the naked eye—not the recommended way to view it, of course.

Venus’ orbit is slightly skewed compared to Earth’s, so Earth, Venus, and the sun only line up this way every 121.5 or 105.5 years. After this much time, Venus gets in the way of the sun twice, each time eight years apart. The last transit was eight years ago. The next, after tomorrow’s, will be in the year 2117.

Transits of Venus were historically used to calculate solar parallax. This eventually led to the astronomical unit, the distance from here to the sun, giving us a way to measure the solar system. Today, scientists’ observations of the transit will help in studying exoplanets.

Do you have a way to live 105.5+ more years or own a time machine? If so, I take back what I said about this being once-in-a-lifetime. Maybe it’s not so special. Even still, what’s the harm in watching?

How can I watch?

If you have vision and plan to keep it, then just going outside and staring at the sun isn’t the method for you. Consider these options instead:

  • Try making a pinhole projector.
  • Use eclipse glasses. These can be bought online or possibly at your local science museum gift shop. Don’t count on the museum shop though—they might have sold out with all the solar viewing going on lately.
  • If you have a telescope, use a filter on the front end (not the eyepiece) to protect your eyes and your telescope. Having a bit of magnification will help turn Venus from a tiny speck to a slightly less tiny speck.
  • Do you or a friend weld? No? Huh. Well, for those who do, wear #14 welder’s goggles to safely view the transit.
  • Do you have access to a device such as a computer, phone, or tablet which can connect to the internet? If not, can you please explain to me why somebody printed my website? If you do have access, check out NASA’s webcast from Mauna Kea, Hawaii.

Have fun, view safely, and keep me in the loop about that time machine!

Exogeology ROCKS! Episode 5

Posted by Zoe on 15th April 2012 in Main Page

I’m pleased to announce the fifth episode of Exogeology ROCKS! In this episode, we hear from Professor Geoff Marcy, Professor of Astrophysics at University of California, Berkeley. Professor Marcy tells us about the search for exoplanets—planets which orbit around other stars.

How are exoplanets found? Are there other Earth-like planets? Could there be aliens on them? Find out the answers to these questions and more in Exogeology ROCKS! Episode 5.

You can watch the previous four episodes here.

Super Harvest Moon

Posted by Petra on 22nd September 2010 in Petra's Blog

Tonight I made a point of looking at the sky, the moon in particular. Why? Because tonight is the night of a “super harvest moon“.

A harvest moon is the full moon closest to the fall equinox. The equinox is a day when the day and night are exactly the same length, and the first day of fall (the same thing happens in the spring). The harvest moon usually happens at least a few days before or after the equinox, but this year’s is special.

Today, there is a full moon. Today is also the equinox. It’s not often the two occur on the exact same day.

I didn’t have the best view of the super harvest moon because it was cloudy where I am. I did see the moon peeking out from behind the clouds though, which was in my opinion beautiful. I also saw a small ring around the moon. It looked a bit like a rainbow. I was amazed at how bright it was outside even with the clouds.

New Photo Gallery!

Posted by Zoe on 13th April 2010 in Main Page

Hello out there! It’s Zoë again with great news! I now have a working Photo Gallery up. Petra posted new blogs recently too, about a post per day, so keep checking up on her on Exogeology ROCKS!

The photo gallery is over on the sidebar underneath the “Games and Puzzles” category. I’ve made 5 different sets of photographs: Mineral and Rock Samples, Geologic Formations, Astronomy Pictures, Spacecraft and Landers, and Telescopes and Observatories. Check them all out! Each photo has a great description of whatever it has in it, and the pictures ROCK!

Until next time, I’m Zoë Bentley and Exogeology ROCKS!

About Me

Posted by Petra on 11th April 2010 in Petra's Blog

If you’ve been reading this blog, you’ll already know me a bit. But I want to give you a better idea of what I’m like. For starters, I’m Petra Stone, an exogeologist. I love geology and astronomy, but I also love writing and traveling. The following are some questions that I’m often asked by people:

What are you currently working on?

  • I’m currently in Iceland working and studying glacial formations. This is research for the Mars mission I’m working on which is going to Mars’ north pole.

What is your favorite planet?

  • My favorite planet is Mars, because I think the geology is fascinating.

What is your favorite color?

  • Purple, of course! That’s why the planet on this website is purple! :)

What is the best project you have worked on?

  • My favorite projects to work on have included: identifying Martian rocks, using relative dating on alien formations, and traveling to far-off locations around Earth. I’ve never been off of Earth, but I’m sure it would an amazing experience. I’ve worked with several astronauts here at NASA who have been off-world and they’ve told me some fantastic stories.

What things do you like to do (what are your hobbies)?

  • Other than my job, some of my hobbies are reading, jewelry making (I bead memory wire bracelets usually), rock collecting (I have a huge collection with geodes, and jasper, and malachite, oh my!), stargazing and learning the myths behind the constellations, and of course, writing this blog! I like finding unique arts and crafts projects too, that can be really fun. I also love hiking. I love getting a great view of the area, and it gives me a chance to look at the rocks. :)
  • Another interest of mine is photography. I can never get my regular camera to take great objects like the moon, but it’s fun to get photographs of other things. I’ve taken photos of places I’ve been, things I’ve seen, and whatever I want to keep a record of or I just think looks cool. It can come in handy to be a fairly good photographer when you’re classifying rock samples (I use several special cameras for my job), but what really ROCKS is when I have the opportunity to take photographs through a telescope. Telescopes at observatories have great cameras for visible and non-visible light! I could never get photographs like those with my own camera. To see some samples of these, be sure to check out the NASA image gallery!

What is your favorite movie and/or television show?

  • I like science fiction movies and TV shows best, but I also like mystery shows. I like non-fiction TV shows too, but I often find long documentaries too long–I prefer shows to have a fictional storyline if they’re going to be really long.  The exception to this is The Elegant Universe. If you’ve ever been interested in physics, that show will get you even more interested! Seeing that for the first time really piqued my interest in string theory and m-theory.
  • My favorite TV shows are The Universe, Doctor Who, and, of course, Star Trek (all series, but Voyager is my favorite).

What are your favorite books?

  • Books I like are usually fantasy, not science fiction. I really enjoyed the Harry Potter series, the Percy Jackson series, the Magyk series,  and similar types of novels. I also really enjoy reading non-fiction science, especially if it has to do with time travel! I read magazines, technical periodicals, as well as the latest papers that my colleagues publish.

Do you enjoy writing?

  • I absolutely love writing! I spend most of my time writing papers about geology and exogeology (since those are the topics I know best and they are what I spend most of my time researching), but every once in a while I’ll take an interest in other topics and feel like I just have to share my findings with the world!
  • I occasionally even write haiku! Here are two examples:

Twinkling balls of light
So many lightyears away
Estrellas lindas

Rocky Mars landscape
Red mesa towers above
Like Arizona

As you can see, there’s a lot more going in my life than just my job. However, exogeology just happens to be what I like most, and a lot of the things I like are somehow related (ultimately everything seems to be related if you think about it enough). That’s just what I like!  It’s why I became an exogeologist.

Geography and Astrology

Posted by Petra on 8th April 2010 in Petra's Blog

Whenever I try to tell anyone what my job title is, nobody understands! I got so frustrated when I went to a geology conference and everybody kept asking me what my sign was! That’s not what I do! I’m pretty sure I’m a Virgo, but I have no idea what that means! The same thing happens when I meet astronomers. They keep assuming that I know stuff like the capital of Nebraska. I am not an astrologer and not a geographer, I’m an astronomer who is also a geologist.

Sometimes people just slip up even when they do know the difference. I had a pretty funny conversation with my grandparents when I tried to explain my job. Here’s pretty much how it went:

Grandpa: “I heard you’re an astronaut now, Petra. That sounds exciting.”

Me: “No, Grandpa. I’m not an astronaut at all, I’m an exogeologist.”

Grandma: “You’re an ex-geologist? I thought you just started this job, whatever it is. What are you doing now?”

Me: “Ex-o. Ex-o-geology is the geology of other planets.”

Grandpa: “Oh, geography!”

Grandma: “Have you made many maps dear?”

Me: “No, not geography. And mapmaking is called cartography.”

Grandpa: “Cartography? I’ve always wanted to draw cartoons. Can you draw Pluto?”

Me: “Grandpa, I’m not a cartoon artist. How’d we even get on that subject? I study things like volcanoes and craters. Geology. And I haven’t tried to draw Pluto. But there’s this spacecraft that’s headed to…oh, that Pluto.”

Grandma: “Oh, geometry, with the shapes!”

Me: “That’s mathematics, Grandma. I’m an exogeologist. That’s a combination of geology and astronomy. I look at space rocks.

Grandma: “Like the astronauts got from the moon?”

Me: “Yes! Exactly!”

Grandpa: “That sounds fun.”

Me: “Yes, it ROCKS!”

Grandma: “So when will you be going to the moon?”

I hope this helps you to tell the differences between exogeology and completely different jobs. My grandparents finally understood after that long conversation, and I can usually get people to at least say it right. People who just haven’t heard of exogeology, or even geology or astronomy, are just part of the job. I can’t blame them really, although it is annoying. For now, I’m Petra Stone signing off. Exogeology ROCKS!

The Search for the Unknown

Posted by Petra on 6th April 2010 in Petra's Blog

As I said before, part of being an exogeologist is getting to explore! From the bright Sun and its flares, to the outermost reaches of the Oort cloud, exogeologists get to see it all! The most exciting part is discovering new things about unexplored places.

Moons are some of the most diverse objects; some are like planets with volcanoes and atmospheres, and others are like asteroids with odd shapes and cratered surfaces. Titan has a thick and hazy atmosphere, which just makes me wonder, “What’s down there?”

Exogeologists like myself decided that Titan was a good place to explore. The Cassini-Huygens mission was and is set to explore and study Saturn and Titan. The Huygens lander detached from the Cassini spacecraft and landed on Titan. It found that there is water ice on Titan, the atmosphere is made of methane and nitrogen, and there even seems to be an underground ocean of liquid water! How cool! Literally, because Titan is so cold being so far from the Sun.

Speaking of being cold and far from the Sun, exogeology is also used for studying Kuiper Belt objects, or KBOs. The most famous KBO is Pluto, the famous dwarf planet. Just let me call it a dwarf planet for the purposes of this one blog, okay? :) Pluto and other dwarf planets are mostly made of rock and ice, like asteroids. We don’t have many good photographs of Kuiper Belt objects, so that’s one thing that I’d like to do in the future: take pictures of KBOs.

The most mysterious places to see are exoplanets, planets orbiting other stars! There are planets of all shapes and sizes out there, and exogeologists are finding more all the time! It rocks that there are other solar systems!

No matter where you look, you just might find something new and exciting! Exogeology ROCKS!

A Day in the Life of an Exogeologist

Posted by Petra on 3rd April 2010 in Petra's Blog

Want to know just what an exogeologist does all day? Well, maybe I can show you just how cool this job is!

When I start working for the day, the first thing I do is see if I’ve received any new data. This could be from other exogeologists or from different spacecraft. I sometimes even get rock samples to analyze. If I do, I’ll take them to the lab. There I’ll test the sample to find out its composition.

There are lots of tests I can do. I can test minerals for streak, hardness, cleavage or fracture, and of course note the color and shape of the crystals. For example, let’s say I was given a mineral sample to identify. It has cube-shaped crystals, and is gold in color.  I rub it on a streak plate, and the streak is greenish black. I’ll scratch it with various tools and deduce that its Mohs hardness is 6. When I break it with a hammer, the place where it breaks is conchoidal (a distinctive curved shape). All these things put together tell me that my mineral is pyrite. If I were given a rock sample, there are a lot of various tests I could do to classify a rock, like cutting a thin slice and looking at it under a microscope.

  • Here’s a quick tip about classifying rocks: If it has bubbles, it’s got to be igneous. Those bubbles are called vesicles, and they’re made when gas bubbles are trapped inside a rock as it cools.

Some days I’ll go to an observatory to do research on a planet. I need to reserve the telescope ahead of time usually. When I used a telescope at the Kitt Peak observatory, I had to reserve the telescope years in advance! But it was worth it. I got some great photographs of Jupiter and a comet during my time at the telescope. I’ve used lots of different observatories, and it’s always been productive. Well, except for that one time when it rained… I had to cancel. I must have been really unlucky that time. But that’s the trouble with astronomy; sometimes you just have to wait for another clear night. At least every other time went well.

Other days I’ll get information from a spacecraft or lander! That’s my favorite part! Once, I got to help with the LCROSS mission and interpret data from the spectrometer. The goal was to find water, and we did! That ROCKS! Since Mars is my specialty, I’ve been receiving data from the Mars Odyssey orbiter, which maps the amount of chemical elements and their distribution. I loved working on that. Maybe I’ll get to interpret data from the upcoming Mars Science Laboratory (MSL). Part of the MSL’s mission will be to study the geology of Mars.

Exogeology ROCKS!

Is Pluto a Planet?

Posted by Petra on 1st April 2010 in Petra's Blog

I figured this would make an appropriate April Fool’s Day post… :)

Whether Pluto is a planet or not is a topic that’s had a lot of controversy since the term “planet” was defined. According to the new definition, a planet must: (1) orbit the Sun, (2) be basically round, and (3) have “cleared the neighborhood” around its orbit. Pluto fits all the requirements except for having cleared the area. Since it’s not a satellite of something else, it’s now considered a dwarf planet.

Pluto has been considered a planet for long enough now though that many people are upset by reclassifying Pluto as a dwarf planet.

I wonder if getting a better idea of what Pluto is like will help settle the debate? The New Horizons probe’s mission is planned to explore the Kuiper Belt and Pluto. It’s scheduled to arrive on July 14, 2015, making a flyby. That’s pretty soon considering how long of a mission it is to get there! I can’t wait to find out what it sees. Meanwhile, the Hubble Space Telescope got some good photographs of Pluto changing seasons, and New Horizons made a flyby of Jupiter.

What do I think? I believe that dwarf planets should be considered a specific type of planet, like terrestrial planets and gas giants. They should be considered just as important as any other planets. But there’s a good reason for changing the definition of “planet”; there are so many dwarf planets still being discovered that the number of planets in the Solar System would be hard to keep track of. Besides, we need a way to distinguish between planets and asteroids, and dwarf planets are somewhere in between. No matter what the definition of planet is though, Pluto is still an important member of the Solar System.

How I became an Exogeologist

Posted by Petra on 31st March 2010 in Petra's Blog

Well, I’ve always been an exogeologist really, it just wasn’t my job title until now.

I’ve always been interested in geology. When I was little some of my favorite books were about volcanoes, and I started a rock collection. As I got older I learned to recognize a lot of different minerals and rocks. I just loved learning about different kinds of lava and eruptions, and about which rocks were quartz and which were pyrite. As I got older I got more books, and my rock collection grew. I read about geology as much as I could. I had a lot of other interests along the way, and I’d focus on that for a while, but geology was always an interest of mine, even if it wasn’t the focus of my life.

I also watched a lot of episodes of NOVA and The Universe. I’ve also always liked space, but never as much as rocks. I mean, lots of kids want to be an astronaut at some point, or an astronomer, or something like that. Space is just too cool not to! Or at least that’s my opinion. I lived in a great place for both geology and astronomy (Tucson AZ), and just for fun my family visited places like the Kitt Peak and Whipple observatories.

At age 13,  I started taking college classes at the local community college. By then I knew all about how geology could be used for things like analyzing moon rocks, and finding volcanoes on other planets. I thought it was really cool that Earth wasn’t the only planet to have geology! And of course, I wanted to learn more. I first took a geology class, because geology was my passion. The very last part of that class was about exogeology. And it was by far the best part. I got to see a picture of a hypothetical planet; I figured out what caused different landforms and how to use relative dating. I also got to look at craters on Earth. I later took an astronomy class, because I wanted to learn more about exogeology, but I didn’t know as much about the astronomy aspect. I knew that this was what I wanted to do. I was hooked, I wanted to be an exogeologist.

I then took more exogeology-related classes, which were mostly just geology or astronomy, one or the other, but they were all really interesting and I learned a lot. A few years ago I started working for NASA as an exogeologist. I’ve done all kinds of neat things since then, but my favorite is figuring out just what caused different formations (especially on Mars, that’s my specialty), like the Valles Marineris, or just rock strata. I love my job! I hope you’ll have just as much fun exploring exogeology as I do!

Exogeology ROCKS!

The Solar System

Posted by Petra on 30th March 2010 in Petra's Blog

You’re probably wanting to know, just what is it that exogeologists do? What do they look at? Why? And what do they find there? Well, let me start by giving you a tour of the Solar System.

The Solar System is a big place, and there’s still a lot we don’t know about it. But we do know where to start looking. We’ve found eight planets, some dwarf planets, comets, and numerous asteroids.

In our solar system we have, in order from the Sun: Mercury, Venus, Earth, and Mars, the inner or “terrestrial” (Earth-like) planets. These are all rocky planets that have similar geology to Earth. Then there is the asteroid belt, a ring of asteroids (big chunks of rock in a ring between the inner and outer planets) orbiting the Sun. And next out there are Jupiter, Saturn, Uranus, and Neptune, the outer or “jovian” (Jupiter-like, the gas giants) planets. And much further out, there is the Kuiper belt, a ring of asteroids and dwarf planets like Pluto and Eris.  There also comets, which have orbits that take them very far from the Sun for years, and then for a short time bring them into the inner solar system. Comets are made of ice and rock, and are sometimes called “dirty snowballs” because of their composition.

And what about the Moon? Well, exogeologists also study Earth’s moon, as well as other planets’ moons. The Moon is covered in craters, made by meteorites (asteroids and other space rocks that hit another object). There are dark areas on the moon that don’t have many craters though, and those are called maria. A mare is a place where a large meteor hit and molten lava seeped up through cracks made by the impact, which then cooled to become one of the dark maria we see on the moon today.

Some of the other planets have moons too, in fact, Jupiter has 63 and Saturn has over 200! Moons can be very different from each other. Some have atmospheres (like Saturn’s Titan), and some are just asteroids and are strange shapes and have lots of craters (Like Mars’ two moons, Phobos and Deimos).

There are lots of planets to explore, and that’s what I do! I like finding out new information about everything in the solar system!

Welcome to!

Posted by Zoe on 28th March 2010 in Exogeology, Main Page

Here on you will find information on what exogeology is, how to become an exogeologist, interviews of various scientists in the field, games and puzzles, a fictional exogeologist’s blog, a photo gallery, and much more!

I started this website as part of the NASA No Boundaries Contest, but plan to let it grow as I learn more about the topics.