Yearly Archives: 2009

astronomy, evolution of galaxies, galaxies, galaxy interactions, galaxy shapes

View from a Distance

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Galaxy Beauty

What if you could move anywhere in the cosmos just to get a good view? Where would you go? The view from our own planet takes in the interior of our own galaxy, plus a healthy look out to intergalactic space. We can see, literally, for billions of  light-years, provided we use the right instruments.  But, what if you could live on a world at the rim of a distant galaxy that was overlooking a pair of interacting galaxies?  What you like this to be your view?

NGC 1532/1 as seen by ESOs 1.5-meter Danish Telescope. (Click to embiggen.)
NGC 1532/1 as seen by ESO's 1.5-meter Danish Telescope. (Click to embiggen.)

This is a pair of galaxies called NGC 1531/2 and they lie about 70 million light-years away from Earth. From this point of view, we can tell they are interacting in a sort of spirited galactic waltz. The spiral galaxy in the foreground is being warped by its dance with the smaller galaxy just above it. The cosmic dance leads to another dramatic effect: a whole new generation of massive stars that were created in the chaos of collision during the dance.  They are visible as the purple objects in the spiral arms.

This view from your living room window on that distant planet I mentioned above is really an exquisite image from the European Southern Observatory. It was made by R. Gendler and J.-E. Ovaldsen who used the 1.5-meter Danish telescope to capture the image.

I often wish we had dramatic views like this from our own back yards here on Earth rather than the skies we do have. On the other hand, using telescopes like the ones at ESO, we really kinda do.  So, enjoy!!

near-earth asteroids, NEOs

Asteroid Threats

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What Will Our Global Response Be When One Comes Knockin’ at Our Door??

In the event that our planet is actually threatened by a collision with an asteroid — that, say, astronomers find that a small rock that can do devastating damage to Earth is actually on a collision course — what will we do?  Whenever this question comes up in public discussions, there’s always somebody who says, “Nuke ’em!”  without regard to the difficulties that sending nuclear bombs out to space to intersect fast-moving asteroids can pose. Yes, it can be done. Anything is possible, given enough time, money, and warning.Yet, is it that easy?  How would it really come down if astronomers said that something was going to whack Earth and we had XX days or months to do something about it?  I can pretty guarantee you that it wouldn’t be like it is in the movies. The whole process would be a whole lot messier and political.

Contrary to the “Duck and Nuke ‘Em” school of thought, the decision to send bombs or laser bursts out toward incoming space shrapnel wouldn’t be taken unilaterally. The United Nations would need to be involved, as well as all the world’s space agencies. Is there a communication program in place so that the UN and the agencies can talk about what to do — quickly and efficiently?  Who would get tapped to make the decision?  Toss the bombs or aim the lasers?  Or is there another alternative? How would we warn the populations of the areas that would be likely to be hit by debris?  What political implications would there be in these decisions? What’s it going to cost? What are we doing now to find these NEOs and predict their orbits?

Well, as it turns out, there are people who are worried about how this will all work. And they’ve issued a report that’s worth looking at. It’s a downloadable PDF and the name of the report is Asteroid Threats:  A Call for Global Response. The authors comprised a committee of experts led by former astronaut Rusty Schweikert; they considered the issues relevant in finding these near-Earth asteroids, and predicting their future orbits and possible collisions, and what we should do in the event one is going to hit the planet. The committee members are part of the Association of Space Explorers (made up of astronauts and cosmonauts — the kind of folk who work in space for a living).

The recommendations in the report have been disseminated in the past three months within the UN.  Schweikert notes that the report has been favorably received, follow-on internal documents are in editing, and the work is incorporated in the approved three-year work-plan for the UN committee on peaceful uses of outer space. So, click on the link above, download their report and have a look at it.