I hope that you’re all doing well and continuing to stay safe and healthy. As many of you know, I’ve been in Shanghai now for two academic years, writing weekly blogs. Thank you so much for following me. However, as my research becomes more time consuming (with some projects wrapping up and others ramping up), I’ve decided going forward, I will be changing the frequency and the format of Astronomer in Shanghai.
Don’t worry. Astronomer in Shanghai is not going away. You’ll still get to see China through my eyes, whether that’s through highlights of museums, delicious foods, fun activities with my friends or within the Jewish community, or photos from my travels and adventures. I’ll still post plenty of fun pictures, too! The main difference will be that I’ll write the blog once per month, instead of once a week, to highlight more of the unique and memorable experiences that I’ve had in Shanghai. I’m currently in the process of figuring out the new format and schedule, but I’ll send an e-mail soon with more details.
Thank you all so much for following my experiences. I hope that you’ll continue following along with me on my adventures and journey in China going forward!
Welcome to Astronomer in Shanghai! Thank you for following my blog and for your interest in my life and adventures in Shanghai! As covid-19 persists in the US and around the world, and you are (hopefully) continuing to remain vigilant, avoiding large gatherings, and social distancing, I hope that you are all staying safe and healthy and that my blog highlights what the world looks like once recovery begins. As things improve, I hope that you enjoy small gatherings with friends and family and other outdoor activities. I’m sure you’ll find these interactions meaningful and enjoyable as I have.
If you have fun following my blog, please subscribe and let me know! To subscribe, enter your name and e-mail on the right side of the page. Once subscribed, you’ll receive an e-mail with each new post. If you have any questions about my life in Shanghai, please ask. Instructions are on the “To Comment” page. Also, feel free to share this blog with anyone else who may be interested in my life and adventures in China!
Life in Shanghai
I hope that this latest update continues to find all of you safe, healthy, and fully vaccinated. Even if you’re vaccinated, I hope that you are continuing to maintain social distancing practices and are generally staying safe. Moreover, as summer begins, I hope that all of you are able to do some fun things with your loved ones outside.
I’m sure some of you have seen the reports about the covid-19 situation in Guangzhou and the surrounding areas in Southern China. The cases continue to rise in this part of Southern China (near Hong Kong). In response to this outbreak (I believe of the delta variant), much of this area (stretching to Shenzhen) has been put into lockdown and requires people coming and going to quarantine for 14 days. There are currently 194 reported cases in Guangdong province, so China is taking prevention incredibly seriously. Thankfully the outbreak has been relatively localized and hasn’t impacted my life in Shanghai. In terms of cases, there are currently just 71 cases in Shanghai (all imported from people returning to China) and the recovery rate is at 96.38%. In Beijing, there are only 13 cases and the recovery rate is at 97.94%. For China as a whole there are 11,892 cases (~ 11,300 in Taiwan) and the recovery rate is at 85.23%.
In terms of Astronomy this was a productive week! I finally finished all the revisions that the Final Reviewer asked for for my DES paper on the evolution of the Stellar Mass – Halo Mass Relation, so hopefully I’ll hear back some positive news soon (and get to submit the paper for publication). On top of that, I spent a lot of my time doing research for DESI, the Dark Energy Spectroscopic Instrument. There’s a virtual collaboration meeting this week and I’ll be presenting my research on the spectroscopic completeness of Brightest Central Galaxies (what fraction will have a spectrum used to measure distance and chemical composition). Lastly, I finally figured out some of the bugs in my Luminosity Function mock catalog! I’m just running some final tests, but I think I’ve solved the discrepancy between the input function and my measurements! So, this week, I hope to finalize that the mock is working!
Last week, I began a series of deep dives into my research. This week, I’ll be talking about the Luminosity Function, since it’s the main project that I’m working on at SJTU. First, a Luminosity Function is simply a mathematical function that describes the number of galaxies at a given brightness/luminosity/absolute magnitude (all three essentially mean the same thing) within a cluster environment. To measure this, you simply count the number of galaxies within a radial region centered on the cluster center (often the BCG). However, because there are foreground and background galaxies, you also need to estimate how much contamination there is in your measurement. To measure a background Luminosity function, you can do the same thing either centered on a random point or measured at larger radial distances from the center of the cluster. Once you have both the inner region measured and the background, you subtract the two and are left with a signal that is the Luminosity Function.
Now that you understand what a Luminosity Function is from a measurement sense, what do you do with it. The Luminosity Function is important because it can tell us how galaxies populate dark matter halos. While the stellar mass – halo mass relation can tell us about the amount of either of these components, the Luminosity Function actually tells us more about the overall cluster population and allows us to determine how many faint galaxies there should be in the cluster environment. Moreover, we can compare Luminosity Functions at different halo masses to determine how halo mass impacts cluster population. If we study the Luminosity Function at higher redshifts, we can search for evolution and growth in different parts of the cluster population. We will also aim to determine whether the magnitude gap can be used to identify differences in the galaxy populations.
For the last few months, I’ve been working on a mock catalog for this analysis. Mock catalogs are simply catalogs of galaxies generated based on an input Luminosity Function (measured by someone else) and positions within a 3D dark matter only (no galaxies) simulation. This is an important tool, because it allows us to determine whether certain signals that we see in the Luminosity Function measurement are predicted by certain luminosity functions or result as a function of our observational measurements. Moreover, using mocks allows us to test the fundamental physics that is input into the Universe. We’ve been working on a mock in order to understand the impact of different background measurements.
I hope that this explanation clarifies what I’ve been working on here in Shanghai. Let me know if you have any questions!
Outside of Astronomy, we’re now in Plum Rain Season, a few weeks long period where it essentially rains every day. Much to my chagrin, even when it doesn’t rain, it’s incredibly humid, so running has not really been something I can comfortably do. As I noted the last few weeks, I’ve continue to go to the F45 HIIT classes for my exercise, which I’m really enjoying!
Even though I didn’t spend a ton of time outside, I still saw some lovely flowers and cool sculptures I wanted to share with you!
I also saw a lot of very cute cats!
As I said in the title for this week’s post, it’s the Dragon Boat Festival this weekend. So, Monday (today) was a holiday. As I noted last week, I unfortunately missed the Dragon Boat races (the main celebratory part of the holiday). Sadly, the traditional treat for Dragon Boat Festival, Zongzi, sticky rice balls with a filling are often filled with meat, so I didn’t get to enjoy those either. However, SJTU does give us gifts for the Dragon Boat Festival. Instead of just giving us snacks (most of which I can’t eat), this year they let us pick presents including household and cooking items. So, I decided to get a cleaning robot!
So far, it’s been pretty useful at getting the hair and dust in hard to reach places, which is great! I’m still figuring out what I’ll name it, but suggestions are welcome!
The main fun activity for me for this weekend was that on Sunday night, my friend Hannah Maia had a birthday orchestra concert and party! The concert was in the Shanghai Concert Hall, which is near People’s Square. When I lived in Xintiandi, I would run by it often and was always curious what it looked like inside. It’s a lovely concert hall, very much in the style of fancy concert halls I’ve seen in the US (even down to the seats not giving me enough leg room). More importantly, the music in the concert was great! While I’m not familiar enough with classical music to have been able to identify the pieces listening to the music (though I was later told that one of them was from Swan Lake), listening to orchestral music was a really nice way to spend an evening. I don’t think I’ve been to an orchestra concert since I was in college, so it was nice to get to go to one.
Food in Shanghai
On Tuesday, Tacolicious hosted a guest chef who was cooking vegan Filipino food! I don’t think I’d ever had Filipino food before, but when I saw that it was all vegan I knew I had to go. While unfortunately, I arrived too late to try the Jackfruit tacos, I got a Lumpia Burrito with smoked tofu, rice noodles, peanut brittle, and roasted vegetables and Sisig fries, fries topped with plant-based meat, picked onions, vegan cheese, and salsa! The side ginataang, coconut stewed taro leaves and mung beans.
The food was fantastic! I’m always excited to try different vegan food and this certainly did not disappoint. I really loved all the different textures in the burrito! I hope that I can try more exciting vegan fare over the summer!
Jewish Life in Shanghai
On Friday night, for Shabbat, Kehilat Shanghai hosted the first of our now monthly community Shabbats. We aren’t able to do them at the Ohel Moishe Synagogue/Jewish Refuge Museum, so we’ll be doing them either in different community spaces or restaurants. For this month, I led the service, which I really enjoyed. Even though we had a small turnout (due to the Dragon Boat festival holiday), it was really lovely to gather together for Shabbat, light the candles, and go through a Shabbat service! It was also really nice to see and hear how much everyone appreciated me leading the service!
Afterwards, we enjoyed a lovely dinner with conversations ranging on topics from sports, to the visa process of getting into China, to teaching in China.
Overall, this was another research focused week. This upcoming week will be pretty busy with the DESI collaboration meeting occupying a lot of my time in addition to other research that I’m working on. However, I know I’ll have some fun things to share with you (including some Dragon Boat themed trivia!).
I hope that you enjoyed hearing about what I’ve been working on, seeing pictures of Shanghai, and hearing about our Community Shabbat! I hope that you all have a safe and healthy week.
Welcome to Astronomer in Shanghai! Thank you for following my blog and for your interest in my life and adventures in Shanghai! As covid-19 persists in the US and around the world, and you are (hopefully) continuing to remain vigilant, avoiding large gatherings, and social distancing, I hope that you are all staying safe and healthy and that my blog highlights what the world looks like once recovery begins. As things improve, I hope that you enjoy small gatherings with friends and family and other outdoor activities. I’m sure you’ll find these interactions meaningful and enjoyable as I have.
If you have fun following my blog, please subscribe and let me know! To subscribe, enter your name and e-mail on the right side of the page. Once subscribed, you’ll receive an e-mail with each new post. If you have any questions about my life in Shanghai, please ask. Instructions are on the “To Comment” page. Also, feel free to share this blog with anyone else who may be interested in my life and adventures in China!
Life in Shanghai
I hope that this update finds all of you staying safe, healthy, and hopefully vaccinated. If you haven’t done so already, I strongly encourage you and your families to get the covid-19 vaccination as soon as possible (if available in the country you live in). Moreover, I hope that all of you are enjoying the warm spring weather (though it’s definitely summer in Shanghai) and are getting to spend some time outside doing socially distanced activities.
I’ll begin this week’s post with a covid-19 update. I’m sure some of you have heard that Guandong Province and Guanzhou (city) have gone into lockdown. For those of you unfamiliar with Chinese geography, this is the southern tip of China, near Hong Kong, so very far away from Shanghai. The lockdowns are a result of a rise of imported cases (though still small numbers, just 130 cases). However, it’s these kind of strict responses, which include mass testing of the populace, that have allowed China to remain being safe throughout the covid-19 pandemic. In terms of cases, there are 71 imported and active cases in Shanghai, with a recovery rate of 96.32%. In Beijing, there are just 9 cases with a recovery rate of 98.3%. The situation in Taiwan remains concerning as there are now ~ 9,600 cases (nearly all the cases in China). For China as a whole, there are 10,049 cases and the recovery rate is at 86.75%.
A few weeks ago, I shared with you that I was able to get a covid-19 vaccination. 🙂 I wanted to update you on how Shanghai has been pushing vaccinations. When I was vaccinated, I had to register with a local hospital for an appointment (that was about 40 minutes away from where I live). However, now, there are mobile clinics that are coming to each residential compound (roughly a block) and offering vaccinations. Today, as I was out for a walk, I saw a flyer for one of these for my own compound. While I’m not sure if I would have been eligible (as a foreigner), I’m glad to see that Shanghai is promoting the importance of getting vaccinated and making it more accessible to everyone! On a funnier note, every time I translate these messages, novel corona virus is translated to new crown virus (which makes sense), but always makes me laugh.
In other China news, this past week, China announced a 3 child policy (in effort to increase population growth, which has apparently stagnated). While I haven’t talked to my colleagues about it, what I’ve heard is that there’s more concern about being able to afford a third child than there is excitement for the opportunity.
In terms of Astronomy, this was another very work focused week. I spent most of my time adjusting and reanalyzing my mock galaxy catalog. While I definitely made progress and fixed some of the bugs, there are still a few issues that seem to be resulting in measurements that aren’t quite in agreement with what we expect, so it looks like I’ll be continuing to tweak this again. Hopefully, my supervisor Ying and I can figure out what the issue is to fix. Additionally, thanks to more help from my Ph.D. supervisor, I was able to finish making the revisions based on the comments from the final reviewer for my DES paper on the Stellar Mass – Halo Mass relation and it’s evolution. So, that paper will be resubmitted to the reviewer at the start of the week.
Since I know many of you aren’t Astronomers, I wanted to explain some of the bigger picture aspects of my research. However, since I’m working on a bunch of projects, I’ll do this one at a time spaced out over a few weeks (thanks for the suggestion Bernard!). To start, I want to explain my research on the redshift evolution of the Stellar Mass – Halo Mass (SMHM) relationship.
In simplest terms, much of my research focuses on understanding the makeup and population of galaxy clusters. In particular, for this project, we are studying Brightest Cluster Galaxies (BCGs) that sit at the center of clusters and whose properties are strongly tied to the underlying dark matter halo (that forms the substructure within which galaxies form). BCGs are ~10-100x more massive than the Milky Way. In quantifiable terms, the SMHM relation compares the amount of stellar matter contained within that BCG to the amount of dark matter within a cluster. While this number itself can be very interesting, we measure how this relationship evolves over cosmic time (we cover ~ 6 billion years in our analysis). In doing so, we aim to understand how these massive galaxies grow and evolve over cosmic time as well as how the halos they reside in grow. This type of insight can be gleaned because changes in the slope of this relationship can tell us how these two masses are changing. Moreover, by adding additional components to our SMHM relation (which we do using the magnitude gap, a tracer for how much brighter the BCG is than smaller galaxies in the cluster), we can characterize how both the cluster population and outskirts of the BCG (the intra-cluster light) are changing as well. This type of analysis allows us to better understand both the formation mechanisms of massive galaxies and also how the dark matter halos they live in assemble. So, to summarize, the goal of my research on the evolution of the SMHM relation is to best characterize how and where massive galaxies grow over cosmic time.
I hope that this summary makes sense to everyone (especially to those of you not studying Astronomy). However, as always, if you have follow up questions, don’t hesitate to ask!
This was a pretty work focused week. As I noted in the title, we’re now reaching the start of summer in Shanghai. While the temperature hasn’t maintained the incredibly high heat every day, it’s very rarely cooler than the mid 80s with about 70+% humidity. So, in my mind, pretty uncomfortable without the AC running. Given that, the temperatures and humidity have reached the point where it’s unpleasant to go for long runs (which are my favorites). However, I’ve continued to go to the F45 HIIT classes as a way of exercising, which I’m really enjoying!
Next weekend is the Dragon Boat Festival Holiday. Shanghai does Dragon Boat races the week before, which I tried to see. However, I didn’t realize how early in the morning the races were being held and by the time I arrived at Suzhou Creek (at 10:30 am) the races were already over, which was disappointing. Hopefully next year I’ll get to see them race!
Despite the heat (which was pretty oppressive over the weekend, it reached the mid-90s), I still have some fun photos to share with all of you including some cool sculptures and some cute cats! Also, the eagle statue is located on the SJTU campus. I hadn’t seen it up close before and it was really cool! Not sure what it means, but will attempt to find out.
Jewish Life in Shanghai
The highlight of my week was on Friday when I had Shabbat dinner with my friend Kate (and her dog Pina)! I made vegan challah (first time on my own, which was surprisingly easy), which came out really well! Kate and I then made a sweet and sour tempeh, which was also really delicious!
After a busy week of work, it was really nice to have a relaxing and fun Shabbat dinner and then spend the evening catching up and talking about different sci-fi tv shows and movies! It was also lots of fun to play with Pina (my favorite dog in Shanghai!).
On Sunday, I subbed for the Bar Mitzvah class for Kehilat Shanghai’s Tov! religious school. Practicing the different prayers with the students and teaching them new prayers brought back fond memories I had of preparing for my own B’nei Mitzvah with Emmet some 17 years ago. 🙂
Overall, this was a very research focused week. I’ve got a lot of presentations and projects wrapping up so it will likely be a busy month of research (though hopefully there will be a bit of a summer break). However, it was really nice to take a break and enjoy Shabbat dinner with Kate and Pina! This upcoming week will be very research focused as I work to finish up some research for the DESI collaboration meeting the following week. Additionally, due to some plans and the Dragon Boat Festival Holiday, the next post will likely be published next Monday (1 day later than normal).
I hope that you enjoyed hearing about what I’ve been working on, seeing pictures of Shanghai, and hearing about my Shabbat dinner! I hope that you all have a safe and healthy week.
