Woah, We’re Halfway There

2 February 2021

It’s Groundhog Day, which is a good time for another newsletter. Astronomically, today is a cross-quarter day, meaning that it is halfway between an equinox and a solstice. It’s also known as Imbolc, Candlemass, and many other names depending on the cultural tradition. Whatever your tradition, we’re now halfway to Spring.

Guess My Age

There were several cosmic discoveries this month, but one mystery that continues to bother astronomers is the fact that we aren’t exactly sure how fast the universe is expanding. That also means we aren’t entirely sure how old the universe is. It all comes down to what is known as the Hubble constant, or more accurately, the Hubble parameter. Recently, observations of distant supernovae seem to show the universe is expanding even faster than we thought. This is contradicted by another study this month, which looked at the cosmic microwave background. It found a slower than expected expansion. None of this disproves the big bang, but it does mean there’s something we really don’t understand about the history of the universe. Perhaps this mystery will be solved by looking at the primordial cosmic background of gravitational waves.

A Massing Evidence

Still, we are learning some fascinating things about our galaxy. A team of astronomers measured the motion of several pulsars so accurately that they mapped the distribution of mass in the Milky Way. This helps us understand how dark matter is distributed in our galaxy. Another team has been measuring the size and mass of Jupiter-like worlds. This is important because we can’t tell the mass of a large planet by its size alone. Everything from Jovian worlds to small stars can be about the same size.

So That Was A Lie

There were also lots of surprising discoveries. A couple of astronomers wrote a program to determine the actual color of astronomical objects as we would see them, based on spectral data. They found that red dwarfs aren’t red, and some white dwarfs look pale orange. Another study found that some white dwarfs can be more massive than the theoretical limit, known as the Chandrasekhar Limit. Another team looked at supermassive black holes and proposed that there could be some stupendously large giants lurking out there. Then there was an interesting look at the speed of light. It’s often said that the speed of light is always the same, but we’ve only been able to prove that the round-trip speed of light is constant. It is impossible to measure the speed of a light beam traveling in one direction.

Spread The Word

Finally, I wrote a post on computer security. We all know that everything from social media to phone apps loves to gather personal data on us. But it is also possible for the very hardware of our computers to gather information. Everyone should push back against this kind of personal information gathering. That’s why my website has no scripts or other trackers, and why it doesn’t have ads. But keeping it up and running depends on you. If you like my site, help spread the word so that more folks can find it.

Until next time, whether you’re holding onto that GameStop stock, singing sea shanties, or watching a Bill Murray movie, I wish you all the best.