The cosmic pie, via Planck. [Credit: ESA/Planck Collaboration]
For cosmology-lovers like me, yesterday was a full, busy day. The Planck telescope released its first full set of data, refining the estimates of the age of the Universe and its contents. I wrote two big pieces, one for Ars Technica and one for Galileo’s Pendulum.
- First Planck results: the Universe is still weird and interesting [Ars Technica]. “By comparing theoretical models to the real CMB, cosmologists determined that dark energy—the mysterious substance driving cosmic acceleration—comprises 68.3 percent of the energy content of the Universe, down slightly from earlier estimates of 72.8 percent. Similarly, dark matter’s contribution was boosted from 22.7 percent to 26.8 percent, while ordinary matter’s share went from 4.5 percent to 4.9 percent.”
- Planck results: our weird and wonderful Universe [Galileo’s Pendulum]. “The big news today is that our Universe is a little older than we thought, has a little more matter in it, and is every bit as strange as we’ve come to expect. Some numbers got shifted around a bit, but things are pretty much what we cosmology-watchers expected. It’s not a bad thing, in my opinion. After all, we still don’t know what dark matter is, we still don’t know what dark energy is, and we still don’t understand inflation completely. Adding weirdness to weirdness is probably more than our poor brains could take right now.”
Charlie Petit at the Knight Journalism Tracker also has a great round-up of articles on Planck, for those who want a more mainstream approach than my “techy” one (to use Petit’s term).
Double X Science chemistry editor Adrienne Roehrich started a new podcast series, discussing stories of the week. Her first cohost was…me! We talked about important women in biochemistry, the size of protons, the science of procrastination, and cosmic rays—all in 15 minutes.
You can download the podcast from the Double X site, or subscribe through Feedburner. Adrienne is also working on listing our content on iTunes; I’ll update when that happens. Update: the podcast is now available on iTunes!
Where do cosmic rays originate? Cosmic rays are mostly high-energy protons from deep space that hit Earth’s upper atmosphere, creating showers of other particles that can be detected at the surface. Some of these protons are so incredibly high energy—meaning they’re moving just a whisker slower than the speed of light—that only exceptional astronomical events could accelerate them. The prime suspect: supernova explosions. Up until now, though, nobody had confirmed this suspicion. However, a new observation using gamma ray emissions from supernova remnants found the telltale signature of particle collisions, which could only be present if protons were getting that extra boost of energy.
On October 15, 1991, a high-energy proton from deep space struck Earth’s upper atmosphere. Known as the “Oh My God Particle”, this proton was by far the highest energy cosmic ray ever seen. This one proton’s energy was equivalent to a regulation soccer ball traveling at 15 meters per second (34 miles per hour). In the two decades following, observers spotted several similarly energetic cosmic rays, which left a big question: what was accelerating these protons to higher speeds than anything we can achieve in on Earth? [Read more….]