Mercury Transit
A Dot on the Day Star
Eating a chocolate donut and talking all things astronomy as I watched the Mercury transit with over fifty people at the Houge Park, was indeed a great way to start the week…
If you’ve never heard of a Mercury transit, it’s kind of a big deal. The planet Mercury crossed the face of the Sun today - a small dot moving across the day star. This is not happening again until 2032 but then, you can’t see that one from the U.S. - the next one here isn’t until 2049. To stress the point, Mercury passed closer to the center of the solar disk today than in any other transit of this century.
So yeah, this is rare, but why?
Mercury is the fastest planet and if it orbited on the same plane as the Earth, we would see a transit every 166 days. But the orbit of Mercury is inclined and we only see a transit when the orbits cross such that Mercury is directly between us and the Sun. The transits of Venus are even rarer.
Micro-Eclipse
A transit is basically a micro-eclipse. Mercury is about the size of our moon but since it’s so far away, it can occlude much less of our Sun and is but a small dot on the disk. The moon, on the other hand, can cover the disk of the Sun and cause a total eclipse. Here’s a fun fact: Our moon is moving away from us too and consequently, there will come a time when it can no longer occlude the Sun’s disk the way it does now. And we won’t have total solar eclipses thereafter.
We’re tiny!
We are not pretending anything else, but seeing Mercury like this puts the scale of our Sun in perspective. Again, Mercury is about the size of our moon.
Finding Exoplanets
Around the time when I was born, we did not know of any planets orbiting other stars. Today, we know hundreds of exoplanets. Transits are very relevant to the way exoplanets are found and studied. Observers look for a dip in the brightness of a star, that occurs when a planet transits across its face - just like Mercury today.
Speaking of transits and dimming of a star’s brightness, I’ll briefly mention Algol, the ‘Demon Star’. It is actually two stars orbiting each other and from our perspective, the smaller star regularly passes in front of the larger brighter one, causing eclipses about every 2 days 20 hours.
SJAA
We hosted an observing session at the Houge Park. We had the club’s Lunt H-alpha scopes set up, one for visual observing and another for live video. We also had a Lunt white light scope for visual observing. In addition to this, a lot of club members and the public showed up with a good mix of scopes and projection set-ups. Some amazing friends also got donuts, bagels and beverages!
Eating a chocolate donut and talking all things astronomy as I watched the Mercury transit with over fifty people at the Houge Park, was indeed a great way to start the week - I’m so glad I dragged myself out of bed at 6:30 AM this morning!
Aurora Borealis
Chasing the Northern Lights
One night in Alaska, cruising around Fairbanks and Denali with my friends, I finally got to see…
I had seen the pictures. I had read up on the physics. On many a night, I had fallen asleep listening to Alan Sklar describing the wonder of northern lights. I had even had the chance to hear Dr. Laura Peticolas talk about her research on aurora at the University of Alaska during one of the SJAA monthly astronomy talks. And of course, this goes without saying, I had dreamed.
Then, one night in Alaska, cruising around Fairbanks and Denali with my friends, I finally got to see.
At first, they were only hazy gray bands spread over the sky - my eyes just couldn’t integrate enough of the light to bring out the colors, although looking through an iPhone camera could reveal the beautiful green. Then, in the wee hours of the morning, as we were driving back to our lodge in Denali, the lights grew brighter and I could really see - the pink, the green, the purple. Interestingly, the best show happened just as we were parking our car at the lodge. I had heard that the aurora are most dynamic around the equinox and so they were, we witnessed a spectacular dance.
As we were chasing the northern lights, I thought about how they can disappear anytime, or offer the best we’ve seen yet. We neither know how lasting the wonders of the present moment are, nor how beautiful the next one - it’s all about living every moment to the fullest, anticipating colored lights on every turn of the road.
My only regret? Not having a good camera! That’s for the next time, I guess.
Chandra
Aiming for the moon
One night, I was out with my guest for the month, an Orion StarBlast 113 4.5 inch Newtonian Tabletop reflector and decided to aim for the moon…
SJAA loaner program enabled me to try out a different scope every month. While I’m yet to make up my mind on which one to buy, I’ve tried a bunch of scopes and learnt a lot about them and met some super awesome people along the way. More recently, I started volunteering for the loaner program, so I could help other people on this journey and learn some more.
One night, I was out with my guest for the month, an Orion StarBlast 113 4.5 inch Newtonian Tabletop reflector and decided to aim for the moon. I had my iPhone with me and it had to serve as the camera. I had no adapter mount and aligning the phone lens with the eyepiece by hand and holding it still turned out to be quite challenging. A colleague then recommended this adapter that works with any phone and it’s been quite useful. A further challenge was to get the focus setting right. All in all, I spent a lot of time and took way too many bad pictures. But a few of them turned out to be decent.
Eclipse
Road Trip to Madras
As I counted down with an amazing crowd, we reached totality and I experienced two minutes of darkness in the middle of the day…
The trip to Oregon to see the 2017 total solar eclipse was undoubtably one of the most fun road trips I’ve ever been on. I went with a dozen amazing people from work. We rented two RVs and drove to Madras, the scene of the totality. With a bunch of gear - some personal and some stolen from our labs, we were all set to capture the eclipse. Needless to say, we had our-optics-engineer-certified protective eye glasses.
Turned out, a lot of people had the same idea. The place was extremely crowded and I remember we paid $200 to park an RV in an empty field. Below is a picture of one of the campgrounds.
The crowd certainly added to the experience - it was a lot of fun to witness the eclipse with so many people. On the other hand, the crowd also caused a massive traffic jam and it took us over 20 hours to drive back to the Bay Area. I remember getting out of the RV and walking along the freeway for a while before hopping back in - that’s how slow we were going!
We reached our campground the night before and spent a good amount of time chatting and stargazing over food and drinks. When I woke up in the morning, the Sun was already up. We set up our gear, made coffee and with growing impatience, waited for the show to start.
The partial phase started around 9 AM. We had a lot of time to play with our cameras and take some fun pictures. Below is one I find particularly amusing. A friend was recording the eclipse with his phone hooked up to his scope. My idea was to take a picture of the phone screen. When I saw a reflection of my face in the picture, I said something along the lines of “Damn, no polarizer on my phone camera”. But someone looked at this picture and said, “That’s a cool selfie!” and soon, a bunch of us were posing for this “eclipse selfie”. I put mine up on Instagram and a lot of people have complimented me on it. Funny what trends catch on!
Around 10:15 AM, there was a buzz of excitement around. The moon got closer and closer to covering our favorite day star. As I counted down with an amazing crowd, we reached totality and I experienced two minutes of darkness in the middle of the day. I even saw a few stars. I got to see the corona - the outermost layer of the Sun visible by sight from Earth only during a total solar eclipse.
Two minutes later, the moon started receding and it was light again. We took another shot at some pictures we didn’t get quite right the first time. And then, when it was over, we packed up and started the loong drive back home.
I had just started driving in the U.S.A and hence, I passed on driving the RVs - I wish I hadn’t, to this day!