This picture of the star formation region NGC 3582 was taken using the Wide Field Imager at ESO's La Silla Observatory in Chile. The image reveals giant loops of gas ejected by dying stars that bear a striking resemblance to solar prominences. Courtesy ESO, Digitized Sky Survey 2 and Joe DePasquale
The process of stardeath is one of those events that is not just the end of a star’s life, but possibly the beginning of another one’s existence. In some regions of our galaxy (and in many other galaxies), the explosion of a massive star in an event called a supernova, not only ejects material from the star that will eventually be recycled into other stars. It also sends shock waves through space that can compress nearby nebulae (clouds of gas and dust). That “ripple effect” starts the nebula down the path to star formation as the material begins to coalesce, heat up, and eventually “turn on” in the process of star birth. If the birth cloud has enough heavy elements to form planets, and the conditions are right, the stellar babies could also be born with worlds of their own. This is what happened to create our Sun and planets, more than 4.5 billion years ago.
The image above is a scene of violent stellar destruction, lit up by strong ionizing radiation (UV light) from nearby newborn stars. It’s a star-forming region in the Milky Way called RCW 57, and the nebula itself (the glowing, loop-filled cloud of gas and dust) is called NGC 3582. Some of the stars forming in regions like NGC 3582 are much heavier than the Sun. These monster stars emit energy at prodigious rates and have very short lives that end in supernova explosions. The material ejected from these dramatic events creates bubbles in the surrounding gas and dust. This is the probable cause of the loops visible in this picture. When the stellar beacons that are heating up this cloud start to die they will also send out clouds of gas and dust like these, and the forces of their deaths may well send the clouds back through a cycle of star birth, creating new stars that will light up the death-clouds of their forebears.
The image was processed by the European Southern Observatory (ESO), using observational data identified by Joe DePasquale, from the United States, who participated in ESO’s Hidden Treasures 2010 astrophotography competition. The activity was organised by ESO in October–November 2010, for everyone who enjoys making beautiful images of the night sky using astronomical data obtained using professional telescopes.
There’s never a dull moment in astronomy. If you’re a skywatching addict, then there’s something for you every night to check out. Last Saturday it was the Full Moon, and it was gorgeous! We didn’t get to see it rise here at the hacienda, but after it cleared the mountain in back of us, the Moon looked great. Tonight is quite clear (and cold), and so maybe later on I’ll step out and check out the starry skies. Right now, Sirius is twinkling low in the southwest and the stars of the Winter Circle are setting soon. Another sign that spring is here for those of us in the Northern Hemisphere, and autumn has arrived for the folks in the Southern Hemisphere.
Mars isn’t in our night-time sky right now. In fact, it appears so close to the Sun that it’s nearly impossible to see without help. But, even though it’s out of sight, Mars is not out of mind. Even the leader of Venezuela has been talking about the Red Planet this week, tying capitalism to the loss of life on Mars. I’m not precisely aware of when Mr. Chavez got his degrees in planetary science OR economics and political science, and I’ve not seen evidence of his research contributions to those fields, but I’m reasonably certain that the lack of life on Mars isn’t due to a plot against Marxist-Leninist paradises here on Earth. It’s amusing to read his rhetoric, even as you see it for what it is — getting in a dig at his neighbors to the north. It seemed like an unlikely topic for him to bring up, but then again, any world leader talking about anything to do with the sky (astronomy or planetary science-wise) catches my attention.
No, Martian life — if it existed — probably never got started down the long evolutionary path that we did here on Earth. Conditions on the Red Planet became untenable for that — not due to Adam Smith-style capitalism, which is a human construct that came long after life took root on Earth. More likely physical conditions were to fault on Mars, entirely NATURAL conditions that existed long before life on Earth was able to do more than look up to the sky in wonder. Changing conditions (atmospheric loss, cooling, geological changes) may well have doomed anything more complex than a Martian microbe to a very uncertain future.
Courtesy MIT/Christine Daniloff.
As it turns out, if a group of scientists at MIT in Cambridge, Massachusetts are right, there’s a tantalizing possibility that life on EARTH may have its seeds on Mars, descending from organisms that somehow made their way from Mars to our planet in the very distant past.
It’s not so far-fetched as it might sound at first. There are some well-established ideas about Mars that lend themselves to this story and make it a plausible avenue of research into the origins of life on Earth.
First, early in solar system history, the climates on Mars and the Earth were much more similar than they are now. Life that arose and flourished on one planet could presumably have survived on the other — if it could get from one place to the other. Second, an estimated one billion tons of rock have traveled from Mars to Earth since the two planets formed. That material was blasted loose by asteroid impacts and sent on its way between planets. Eventually, the “stuff” from Mars hit EArth. Third, microbes have been shown to be capable of surviving the initial shock of such an impact. So, if there WAS life on Mars (in handy microbe form, which is an easy way to transport living material), and it somehow caught a ride on an outbound rock, then given a good set of orbital conditions, there would have been NOTHING stopping that rock and its life-load from getting here eventually. When you look at the orbital dynamics of our two planets, it turns out that the chances are a hundred times better for rocks to travel from Mars to Earth.
I know that sounds surprising, but life is amazingly resilient, and in fact, there is evidence such microbes could also survive the thousands of years of transit through space before arriving at another planet.
So if life got started on Mars first, and it got blasted off the planet in a meteorite impact, then some hardy microbes could have been carried here to Earth. And, if that’s true, then Ray Bradbury’s final scene in “Martian Chronicles” is more prophetic than he may have thought when he wrote it back in 1950. But, instead of finding those humanoid Martians staring at their own faces in a canal on Mars, all we have to do is look in the mirror in our homes here on Earth.
Of course, there’s a lot of work to do to prove this hypothesis, but I find it kind of poetic and interesting. We — you, me, Mr. Chavez — all the people on Earth — really COULD be Martians, and here all along we’ve been yearning to explore that RedPlanet so far away. And, we’re using technology that is the fruit of the capitalism that Mr. Chavez regularly decries on TV, radio, and the Internet — ironically enough, media methods that also depend more on capitalist investment than he might feel comfortable with.
But there you go. Astronomy and planetary science lead one down some interesting paths, and not always scientific ones. I think it’s rather interesting that even though his politics aren’t the same as mine, Mr. Chavez has an awareness of Mars and its past and future. I wonder if he stargazes, too?
