A Noir Look at Mercury’s
Mysterious Surface Evolution

Mercury’s horizon, as seen by the MESSENGER mission.

The name’s Basin, Caloris Basin, and I’m a planetary science detective. Perhaps you’ve heard of me. Of all the planets in all the solar systems in the cosmos, I’m interested in Mercury. It’s a classy place, with a great surface to boot.

So, until just a couple of days ago, things weren’t going too well for me. I’d been stonewalled with a lack of knowledge about ALL of Mercury’s surface. It was tough, and I was down to my last… well, let me tell you the whole story.

It was late on a Friday afternoon in mid-January. Business was slow. It had been for years, ever since the Cassini mission had launched, followed by New Horizons. Everybody’s attention was turned toward the outer solar system, or near-Earth asteroids, or dwarf planets beyond Neptune.

And, it seems that ever since I’d cracked the case of the sulfuric plumes in the Venusian atmosphere, inner-solar-system detective work had just dried up. Pancake eruptions on Venus were so last-century. Even Martian dust storms weren’t getting as much press as they used to. Oh, sure, the occasional asteroid-impact threat on Earth raised a little stir now and again, but in the main, it seemed like nobody cared about the inner planets any more. A pity.

I mean, there was Mercury, waiting to be explored again. Even though Mariner had given it a quick look back in the 1970s, its glory days weren’t over. Not by a long shot! Sure, its surface would be at home on a black-and-white scene from a 1940s detective movie set (without the rain and fog, though). And sure, it’s a bear to observe from Earth. But, Mercury’s got as many mysteries as those outer planets, and it’s a darned sight more rocky!

Still, all the hot researchers and their grants (and grad students) were out there at Saturn, and using Hubble and ground-based telescopes to poke around Pluto and the Kuiper Belt. They were flush with success, invoking cryovolcanism right and left to explain what they were finding! Yet, for my NSF grant money, there was a lot of good science to be done in the inner solar system. So, I resigned myself to having to wait for a while. I knew that soon I’d eventually have my day in (or actually near) the Sun. Continue reading The Case of the Lobate Scarps…

Mars Again… and Again

Mars Rover Spirit Looks Out Over a Low Plateau

Mark and I just announced the fulldome incarnation of our long-popular show MarsQuest—something that’s been a long time coming. The show itself has had several incarnations, beginning in 1988 when we created a show about Mars called “The Mars Show” and it was basically a slide show with a soundtrack. (Why that title? We could never think of a better one, so it kept that name for quite a while.)

In 1996, we got together with a group of people at the Space Science Institute in Boulder, Colorado, to talk with them about a traveling exhibition they were creating called MarsQuest. They wanted a planetarium show, and by golly, here we were with a planetarium show that we wanted to update. After a few meetings, we had a deal, and the rest, as they say, is history. The MarsQuest exhibition has finished its run around the country and is retired to a museum in Florida. But, MarsQuest the planetarium fulldome show is still very much alive and kicking, bringing info about the Red Planet to all and sundry.

It seems that I write about Mars every few years, and people often ask why. It’s simple: I’ve always been taken with the Red Planet. It all goes back to a game we used to play when I was a kid, about exploring Mars. And that’s part of it. As I got older, I read more about the planet, especially when in 1976 we actually landed a spacecraft there.

So, it was only natural that I’d eventually end up writing a documentary script about it. And revisiting it as more spacecraft send back more images and data about this planet. Not only did the game from my childhood spurred MarsQuest, and a scene in SkyQuest, a show we did for the National Air and Space Museum’s planetarium. So the game I played keeps coming back in one form or another.

And it continues. As more Mars images and data come in, I continue to work on other Mars-related presentations. For me, this dry and dusty desert planet is also one of the most tantalizing places in the solar system, and if I were of the right generation, a place I could have once considered exploring in first person.

A Year of Astronomy

 

 

 

A hundred countries (and counting) have signed on to participate in the International Year of Astronomy, which runs throughout calendar year 2009. The IYA planners envision the year as a time when people take renewed interest in astronomy and science, from school children to members of the general public and the astronomy community (both professional and amateur).

On their web page the International Astronomical Union, which is spearheading the organization of IYA 2009, states:

The vision of the International Year of Astronomy (IYA2009) is to help the citizens of the world rediscover their place in the Universe through the day- and night time sky, and thereby engage a personal sense of wonder and discovery. All humans should realize the impact of astronomy and basic sciences on our daily lives, and understand better how scientific knowledge can contribute to a more equitable and peaceful society.

Now, we’re a planet full of people, all with different languages, philosophies, levels of income, education, science interest, and political backgrounds. How can astronomy be something we can all appreciate? It’s pretty simple really: we all have access to the sky. There isn’t anywhere on Earth where you can’t look up and see the sky, day or night. Granted some places have hazy, light-polluted skies. But, even in the worst places, you can see a few stars at night or the Sun, or the Moon. Astronomy is universal.

And that’s the beauty of International Year of Astronomy. Anybody can do something with it, as long as it’s related to the “Cornerstone Projects” that the IAU and IYA planners have developed. What are those projects?

100 Hours of Astronomy
The Galileoscope
The Cosmic Diary
The Portal to the Universe
She is an Astronomer
Dark Skies Awareness
Astro&World Heritage
Galileo Teacher Training Program
Universe Awareness
From Earth to the Universe
Developing Astronomy Globally

You can read more about these projects the IYA home page linked above. I’m particularly interested in the Galileo scope, the Portal to the Universe, and the She is an Astronomer projects. Check out the pages and see if there isn’t a project that excites you to participate, in whatever way you can.

Astronomy for Everybody

Noreen Grice is one of the most amazing individuals I know. She works at the Boston Museum of Science and has single-handedly brought astronomy to people who can’t see the stars. Noreen took the unheard-of idea of teaching visual astronomy to the blind by using Braille books. Her first one was Touch the Stars. That one has been followed by Touch the Universe and Touch the Sun. Now, her latest book, Touch the Invisible Universe is coming out, according to a press release that is showing up at various NASA-funded sites. It is being distributed by NASA to schools for the blind, and various libraries where it will be a resource for visually impaired people.When it comes to ultraviolet, x-ray, gamma-ray, radio, and infrared radiation, we’re all blind to the universe in those wavelengths. So, I think it’s pretty cool that Noreen has taken a subject within astronomy that gives ALL of us an insight to things we can’t otherwise see (wavelengths beyond visible (optical) light), and explains it all in a book that uses Braille, large print, and tactile “graphics” of astronomical objects, for those who cannot see at all. Astronomy is for everybody, and Noreen’s new book brings that lesson home in an unforgettable way.

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Black Holes: Not Just for Science Fiction Anymore

I’ve always been a sucker for mysterious things in outer space. No, not little green beings or monsters from Cryzalix IV or alien face-things on other planets that turn out to be eroded mesas. I’m talking about the real deal: strange things that really do exist, but when scientists first think about them, or observe them, they kind of scratch their heads and go “huh?” Black holes fit in that category. And, you know what? A LOT of people are really curious about black holes. If you’re a planetarium lecturer or a scientist who does outreach, or a teacher who finds time to fit in some astronomy between all those other unfunded educational mandates you have to follow, you already know this. Black holes are just about the first thing anybody asks about as soon as the topic of astronomy comes up. No, really. It’s true. (Well, sometimes they ask about astronaut love triangles, but I don’t want to go there and neither do you…)Anyway, I wish I had US$5 (or 5 Euros, I’m not picky) for every time I’ve been asked about black holes while standing in a line at the store, or sitting on an airplane talking with somebody, or answering an email from somebody who’s read my site. Black holes are just that popular. Yet, I remember a time when they were pretty much flying beneath the public’s radar.Back when I was a kid a few decades ago, black holes were taken seriously more as theoretical constructs—objects that mathematical and scientific models said could exist, but nobody had actually seen in real life. There are a lot of science fiction stories about using wormholes to ride around the universe in; those are based on some theoretical constructs called Einstein-Rosen Bridges.

Pretty speculative, but interesting to think about. And, certainly TV and movie science fiction stories often depend on spectacular special-effects wormholes to keep people moving. But, right now those remain on the dreamers’ drawing boards while astronomers study the real-life black holes that are turning up everywhere.

So, black holes hide in a lot of places. Astronomers have known for a while that they exist in the hearts of many galaxies, and they’re also the powerful engines under the hoods of quasars. Back when I was a teenager, Quasars were TV sets. Now they’re better known as the bright, distant and extremely active core regions of galaxies. Radiation pours out of these things in many wavelengths of light, including x-rays and radio waves.

Last week at the American Astronomical Society, we heard a LOT about black holes. I was especially intrigued with the story out of Vanderbilt University that there could be hundreds of rogue black holes roaming around our own galaxy. They got the galactic heave-ho from the globular clusters where they formed.

But, for my money, the most interesting black holes are the ones that lurk in the hearts of galaxies like our own. You can’t see the one making its nest in the core of the Milky Way because it’s hidden behind clouds of gas and dust. And, well, you really can’t see a black hole anyway. What you DO see is the chaos that is created when a lot of matter swirls into the black hole. In addition to the stars, gas, dust, and other stuff that is getting sucked into the black hole, powerful and twisted magnetic fields are funneling superheated plasmas out to space, in the form of jets.

All this activity gives off those x-rays and radio waves I just mentioned. And, the heat in the region also warms up clouds of gas and dust, which glow in infrared wavelengths. So, looking for black holes is a multi-wavelength (except for visible light) proposition, particularly for the Milky Way’s black hole.

If you want to read more about the black hole in the Milky Way’s core, I recommend a very cool book called The Black Hole at the Center of our Galaxy by astronomer Fulvio Melia. I reviewed it a while back for Sky & Telescope Magazine, and I still remember what a great read it was. There’s a lot we know about black holes, and they’re not just for science fiction any more. They play roles in everything from the earliest galaxy formation to stellar evolution.

The latest installment of my little vodcast series about all things astronomical is also about black holes, specifically the one at the heart of the Milky Way. Check it out!

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