Saved by Juno
One of the coolest space mysteries of the last few years has to do with an oddly dimming star located about 1470 light-years from Earth. This star, called KIC 8462852 (also nicknamed Tabby’s Star for the astronomer who discovered the dips) first garnered media attention back in 2015 when the Kepler telescope’s data revealed a series of unusually large, aperiodic dips in the star’s brightness (flux) that went as deep as 20%. There's also evidence - hotly disputed - that the star's overall brightness has declined by about 20% over the last century. F-type main sequence stars like KIC 8462852 shouldn't behave this way.
What got the headlines when the story broke was the slim possibility that the culprit was an advanced alien civilization building a Dyson sphere. According to this silly theory, what Kepler was seeing was the enormous megastructures built by a highly developed space-faring civilization. Perhaps this was evidence of a Dyson Sphere (or a Dyson Swarm) being constructed to harness the star's energy to meet what would be immense energy requirements. This would, the theory goes, explain the strange dips. You see, dips so large and aperiodic couldn't be explained by any natural phenomenon that we've seen up to now.
A planet as massive as Jupiter would only block about 1% of the star's light, not 20%. Also, the randomness of the dips seemed to rule out objects in predictable elliptical orbits like planets. Of course, as a fan of good science, I thought this alien megastructure theory was ridiculous, the product of the feverish imaginations of those who have read too much science fiction. I only donated $150 to the Kickstarter Campaign so that astronomer Tabitha Boyajian and her team could pay for telescope time to find the real culprit, which was no doubt a totally exciting natural explanation.
So I'm happy to report that recent observations have pretty much put the final nail in the alien megastructure theory. All the evidence points elsewhere. And where you might ask? Maybe alien mini-structures, at least? Well, as of 2018, it looks like the leading hypothesis for the dimming is dust since the star experienced less dimming in the infrared than the ultraviolet. What this indicated was that the material orbiting the star was only a few micrometers in thickness. If the material were thicker, light would dim at equally across the wavelength spectrum (Universetoday.com).
That's fine, awesome even, and shows just how good science works by methodically analyzing the evidence to come to better and more reliable explanations. You have to follow the evidence, right?
Putting Things Back in Perspective
I'll confess I was hoping for something else, something a little more tantalizing, something a little more, well, science fiction. What happened, in the end, is what always seems to happen with astronomy. When the lid is lifted off the plate, and the mystery revealed, it's just another steaming pile of vegetables. Yeah, I know those carrots and broccoli, like good science, are what's good for us. But dammit, can't there be something mind-blowing now and then, something that makes us all gaze in wonder at the night sky and proclaim, "Whoa!"? Dust just leaves me dry. From here on out, the research will be to discover just what kind of dust we're looking at and where it comes from. That's nice, but where are the Vulcans?
Still, upon further reflection, this reaction was unjust. After all, I've spent the last two and half years hoping against hope that a more in-depth look at this star would reveal something more than dust while at the same time pretending that all I cared about was finding a perfectly natural explanation.
That's my fault, though, since as a member of the general public (read: science stupid) I want my science to be a little more Star Trek and a lot less C-Span. After that initial feeling of letdown, after digesting that bland metaphorical plate of steamed vegetables and telling myself how good it was for me, Juno came to my rescue.
Saved by Juno, Cassini, New Horizons, and Hubble
For those of you who don't know, Juno is NASA's space probe (mission overview) that has been orbiting Jupiter for a few years now. In that time, Juno has done numerous flybys of the gas giant and taken some stunning photographs. Seeing the most recent photos by Juno put everything back in perspective and reminded me of the many other amazing things that NASA has accomplished in the last few years.
Take a look at these magnificent photos below, combining brilliant science and advanced technical capability to show us earthlings the breath-taking beauty that exists in our celestial backyard. Here's the actual link to NASA's Juno page, but for a tiny sampling of what the little probe has done over the last couple of years, take a look at some of these photos and gaze amazed at how art and nature can merge to take your breath away.
Finally, take a look at this short video. It was made with images taken from the Juno Cam and takes us on a simulated journey into Jupiter's clouds.
This animation takes the viewer on a simulated flight into, and then out of, Jupiter’s upper atmosphere at the location of the Great Red Spot. It was created by combining an image from the JunoCam imager on NASA's Juno spacecraft with a computer-generated animation.
Juno is only the most recent success by NASA, but it got me to thinking about everything else they've done or are still doing. Cassini's mission to Saturn comes to mind. On 15 September 2017, the Cassini probe went out in a blaze of glory, plunging itself into Saturn's atmosphere to cap an epic twenty-year mission.
Before that, however, Cassini had explored the Saturn system in greater depth than ever before, sending back thousands of breathtaking photos, not to mention landing the Huygens probe on the methane-shrouded moon, Titan.
The New Horizons probe flyby of Pluto back in 2015 gave us the first stunning photos and data from the dwarf planet. New Horizons is not done, though; it's continuing its journey to explore the Kuiper Belt at the outer edges of our solar system.
As for current missions: The Curiosity Rover has been exploring the surface of Mars since 2012, and in that time has covered over ten miles on the red planet's surface beaming back information about conditions on the Red Planet.
The Hubble Space Telescope has been expanding our knowledge of the universe for an incredible 27 years and could continue operating until the 2030s or 2040s.
Hubble was instrumental in helping us fine-tune the age of the universe; it has discovered galaxies and supernovas billions of light-years from the earth; and, most famously, it photographed Jupiter when the Shoemaker-Levy 9 comet slammed into it back in 1994. The data gathered from each of these missions will keep scientists busy for years and will leave humanity with a much better understanding of the universe we live in.
And this returned me to where I started, back with the Kepler Space Telescope. To date, Kepler has discovered over 2300 exoplanets, including 30 small terrestrial planets orbiting in the habitable zones of nearby stars. It was data from Kepler, analyzed by citizen scientists, that led to all the excitement about Tabby's Star in the first place.
For the first time, citizen scientists have made major contributions to the search for exoplanets by sifting through the mountains of data collected by Kepler. In other words, without their help, we may have never known about Tabby's Star in the first place. Nobody planned on this; it's just bonus science, a discovery of something new, all thanks to the efforts of both professional and amateur scientists alike.
Yes, okay, it's just dust, but the point is that this will reveal something new about the universe that we don't already know. Who knows what that will be? So, if there's another Kickstarter campaign by Ms. Boyjian and her team to study this dust in more depth, will I contribute? Absolutely! Because you never know. Maybe what we're seeing is the dust-sized debris from some epic space battle that took place a long time ago in a solar system far, far, away. Ridiculous? Maybe, but we'll just have to investigate to be sure, won't we?
The truth is out there!