General

Marusa Bradac: I do astronomy because it fascinates me. And it is the simplest things about it that amaze me most. I still remember times when I was a little girl watching stars with my dad in my home country Slovenia and wondering, "how far away are they?" I also remember how exciting it was when I first saw the Andromeda galaxy in our backyard. These days I moved on to much bigger things called clusters of galaxies. But the excitement of the question of how far away they really are is still there.

This image was uploaded with the post 50 Years of NASA.

Last week marked the 50th anniversary of President Dwight Eisenhower signing the National Aeronautics Space Act. This little wiggle of the pen created the agency we all know today as NASA.

Nine years ago this week, Chandra was launched aboard the Space Shuttle Columbia (sadly lost in the tragedy of 2003). While the satellite has performed excellently since it was deployed on July 23, 1999, there was a little drama in getting it going. You can read about some of the angst-inducing moments in the days leading up to launch in our Chandra Chronicles from that time.

This week, many Americans will celebrate the 4th of July by enjoying fireworks. We love to see the explosion, followed by the colorful debris field as it expands and rains down from the sky. And, fireworks are often slightly different from one another – even if they originate from the same type of explosion. Of course, if they have different types or proportions of chemicals before in the explosive itself, the fireworks can look dramatically different. And, don't forget that the environment they explode into – include wind or clouds of smoke – can affect how they look.

In the last year we have seen tremendous development in visualizing the Universe through the digital world. Google Sky and Wikisky are examples of this progress. These interfaces have taken well-known all-sky surveys and detailed observations to create virtual observatories that show our nearest planetary neighbors, like Mars and Jupiter, to the most distant galaxies in the Universe.

One of the most important tasks involved with having telescopes in space is keeping them at the correct and constant temperature. It's not just because telescopes like Chandra like to be comfortable – it's crucial in making the instruments perform as they should and return accurate science.

When we talk about what Chandra observes, we're usually discussing things like black holes or galaxies or stars. But Chandra is a pretty amazing telescope and it can study many things in the Universe – including the Earth.

Here's a piece of high-energy astrophysics trivia (you never know when you might need to know these things). Where does the "X" in "X-ray" come from?

Speaking in broad generalities, there are two main classes of physicist: those who generate new hypotheses and those who generate new data. The former are called "theorists" and the latter, in most of physics, are called "experimentalists." In astrophysics, we're called "observers" because we can't do experiments in the traditional sense. We have no knobs to turn, no switches to flip; we can't turn the dial to a maximally spinning black hole just to see what happens (oh, what fun that would be!). Instead, we look at what's already there and try to figure out what it is we're looking at.