Tuesday, June 16, 2015

Rise and Shine, Philae

Summary: Remember when there was a huge celebration because as a human race, we landed a rover on a comet? It was thrilling at the time, but we lost contact with the rover after it bounced into the shade of a cliff. Now the comet has tilted to allow sunlight to reach Philae and the rover has reached out to Earth.

A few very short message was received but it gives scientists hope and affirms that the rover may be able to still carry out its mission. There is not much else known at this point but the comet will be shifting into a position with more sunlight so more can be understood about the condition of the rover.

BBC News

Tuesday, June 9, 2015

LightSail Test Sucess

Summary: Launched on the 20th of May, the final step of preparation for the LightSail was launched. This was a test sail that would practice unfurling the sail and send back pictures to Earth. I am incredibly excited by this mission and have been ever since I saw the concept art nearly fifteen years ago as a possible design for futuristic spacecraft.

The LightSail is designed to work just like a sailboat; only instead of the wind filling the sail, it is light from the sun. Photons emitted from the sun will push the sail outward and the spacecraft will sail happily along. Even when it has passed beyond the reach of the sun's light, momentum will keep the craft going, even if not as fast.

This would not be a design intended for human travel since it is so slow, but more as a method of sending data gathering probes out into space with no power needed for propulsion beyond adjusting the sail. Furthermore, I believe this sail is not going to be able to tack and sail into the headwind. It will be a one-way mission.

Planetary Society

Monday, May 25, 2015

10 Facts about Antimatter

Summary: Remember when this blog started and I tried to keep it focused solely on antimatter? That turned out to be too specific but I am once again able to get back to the heart of this blog. While not and advancement in antimatter studies, this is a recent article on ten facts you may not have known about antimatter. Contained within the article are helpful links to more topics related to antimatter that can quench your thirst for knowledge. Enjoy.


Friday, May 15, 2015

The Case of the Strangled Galaxies

Summary: Galaxies are considered dead when they no longer are producing new stars. It is still unclear what causes this process but what astronomers do now know is the most common time scale of them dying -- approximately four billion years. Astronomers are calling this process strangulation.

Astronomers are able to tell how quickly the galaxy died based on the metal content remaining in the galaxy. The more stars that are being formed in a galaxy, the more metal content is seen. The way it works is simple. If a galaxy dies quickly and quite violently (for instance if the cool gas that fuels the star formation is suddenly ripped away), then the stars immediately stop producing and the metal content remains the same. But if the galaxy if cut off from the supply of cool gas but still continues to produce stars, using up the last of the supply, the metal content in the galaxy grows and grows until it "suffocates".

The difference was seen when comparing the spectra of light emitted by red, passive galaxies and blue, star-forming galaxies. With the data from Sloan they were able to see that the dead galaxies were, on average, four billion years older than the active galaxies. This is consistent with the amount of time the astronomers had calculated it would take to burn of the remaining amount of gas supply whilst strangling to death.

While the astronomers are now confident that death by strangulation is the most common way a galaxy meets it's ultimate end, it is still not clear what causes this. The most likely suspect at this point in time seems to be overcrowding which would lead to a greater probability of disruption to the gas supply, but this would need further investigation.

BBC News

Friday, May 8, 2015

LHC is Up and Running

Summary: After the scheduled two year shutdown and update of the Large Hadron Collider at CERN, the LHC is back and ready for even higher energy collisions. It began smashing particles again Easter Sunday at energies of 450 GeV. Amazingly enough, this is a lower energy and will be used for calibrations before the truly record breaking energies of 7,000 GeV starting on June 1st.

BBC News

Update: Test collisions have broken the energy record already at 13 TeV.

BBC News

Friday, March 27, 2015

A Shattering of Old Dark Matter Theories

Summary: Thanks to new data, further theories of the nature of dark matter have been smashed to pieces! Pardon me for being excited about leading theories being wrong but that only means that I may have a part to play in developing the correct theory. So what has changed?

It turns out dark matter really doesn't seem to interact with anything apart from gravity. It doesn't even interact with itself. The study was conducted my using the Hubble and Chandra to look at collisions of different galaxies and watch the dark matter. Well, it looked at the gravitational lensing since dark matter itself is essentially impossible to see.

In the way science should work, Dr. Massey explains that "if you want to figure out what something is made out of, you knock it, or you throw it across the room and see where the bits go." The surprising part was that unlike the stars that slide past each other and the gas clouds that come to a halt in these collisions, the dark matter "seems not to interact with anything at all." Rather like a ghost, it just glides through the other dark matter like it's no big deal. Since it doesn't even interact with itself, many prominent theories for what dark matter is has now fallen apart. Which means exciting new possibilities for the rest of us in the future. 

BBC News
Science Mag

Sunday, March 22, 2015

Rosetta's Comet is Slowing Down

Summary: Despite the rover not being turned on again, astronomers are still learning new things about the chosen comet. For instance, it's changing rotation speed. The comet takes approximately 12.4 hours to complete one rotation, only that rate seems to be slowing down by one second per day. It seems like a small change but that is big in astronomical terms. It is actually a faster rate of change than in September. Back then it was slowing down by 33 milliseconds per day. (And right there is a differential equation for those who are so inclined.)

Scientists know the reason for this. The comet 67P is becoming more active which means there are gas jets shooting out of the rock and serving as propulsion, much like a rocket, only in the opposite direction of rotation, thus slowing it down. The jets actually shoot out of the comet at 800 meters per second and extend a few kilometers off the surface.

Astronomers found this out thanks to Rosetta still being in orbit around the rock. In order to keep the satellite in the correct trajectory, the navigators were using a system of landmarks on the surface to keep track of position. Only the landmarks were coming into view at a different time than expected.

BBC News