YOUTUBE: A NEW BRANCH OF OUTREACH

Hi everyone!

I feel obligated to apologize for neglecting my personal blog while working on very new virtual outreach content. Hopefully you all understand the struggle! Between juggling research, preparing for my PhD defense (and thesis writing πŸ₯΅), post-doctoral grant applications, my personal blog, local volunteer work, etc, etc, and NOW this YouTube channel (‼️), my plate is pretty full πŸ₯΄.

The (On) Planet Nine YouTube channel‘s first ever season has commenced! So, I am accordingly putting all of my energy into these videos and sharing them. The first season is anticipated to end in February, and when that happens, I will re-arrange priorities to continue writing blog posts about ongoing research. I know there are a couple loose ends to be tied, and I also haven’t shared much regarding my current PhD research, so I’d love to do that more, too!

In the meantime, it would mean so much if you could watch/view/share our newest YouTube videos among your networks! Of course, I hope you enjoy the content and can think of one or more people who may also enjoy it πŸ˜„. Science is meant to be shared and rejoiced!

I do a little shameless plug of all of our links and latest available YouTube videos below! Lea’s episode two just came out TODAY and it features a little live music in the introduction ☺️.

Subscribe below! We are on YouTube, Facebook, TikTok, Twitter, and Instagram!

Social media handle: @onplanetnine

Series 1: Discovering the Universe

NEW! Episode 2

Episode 1

Series 2: The Basics to Astrotools

Episode 1

Did you know we also feature guest interviews with other astronomers??

Next up is the incredible Dr. Alex Filippenko crashing On Planet Nine and telling us about how he (and his team ofc) ended up discovering the acceleration of the expansion of The Universe! The full video releases November 27 (NEXT SATURDAY!) so watch out πŸ‘€

Get yourself hype about Alex. He is seriously an amazing presenter and I guarantee he will make you giddy about science!! πŸ€ͺ Below is a Tedx Talk he did back in 2013. He has also been featured on The Universe (more than a dozen times, actually).

Episodes alternate and are released on a weekly schedule.

(A) SURPRISE!

I have been waiting way too long to share this exciting project with you all! About one year ago, a dear colleague and friend who was in the same research group as me at Clemson was preparing to graduate and was asking the group for help with her proposal for job applications. So, I read her proposal, and at the end I read that she has plans to start a YOUTUBE CHANNEL for educational outreach. If you know me then you know I messaged her with my comments on her proposal and said I WOULD LOVE TO HELP WITH THE YOUTUBE CHANNEL IDEA.

A few months later we meet up, and it’s FIVE (5!!) of us that show up to a meeting, all with the same Clemson advisor (Marco must be proud πŸ₯²). We had all read her proposal and said LET’S GO!πŸ—£ πŸ“£ 🀣

Over the next year, we prepared what this channel will be about, and man, it is no joke making videos and content of all kinds — it is a TON of work πŸ₯΅. Mainly because we all also have our day jobs, so juggling all of this has been an exciting challenge.

Without further ado, please go check out the channel we are building! We aim to share our passion for science with anyone and everyone because, as Nuria points out in the trailer below, it’s contagious! πŸ˜‰

We plan to officially roll out our first season starting November 6 so be sure to follow/subscribe to your preferred platform (or all of them 😁 ) to make sure you get the latest news in the cosmos! 🌠

We aim to be active as an outreach group on our Youtube channel, webpage, and social media platforms, and I provide them all below! Go follow/subscribe/interact with us to help us grow ☺️

GREATER BOSTON LIVING

Noah and I have been living in the greater Boston area for a little over 1 Β½ years now! This September first has marked our third time of moving around in that same time frame πŸ˜…. Don’t even ask how many other times we’ve moved around before even coming up here (it’s a ton, we have it just about down to a science now…). We initially moved into a super cute Cambridge neighborhood and lived there with all three of our pets for about 10 months before we crossed the river (a whole two miles) into the Brighton village of Boston city. We just spent the last year being walking distance to the river and that has been relaxing, to say the least.

Images below are just a few from our first neighborhood we lived in in Cambridge. It is such a cute area!!😍

Cambridge

Moving up North in the dead of winter from Clemson, South Carolina was a pretty big change to say the least. Add into the mix a pandemic and you have two very confused Southerners. We tried our best to take advantage of the city, but hopefully you will understand our slow progress πŸ₯².

I’ve experienced a lot of weird stuff that was new for me — Northern accents, Northern attitudes, snow! Lots of snow, including shoveling my car out and learning why it’s best to not just wait for the snow to melt… Then, there’s triple the cost in everything, parallel parking, the list goes on.

I have to say – the jury is still out on whether I see myself ever choosing to remain in the city. I still really love the idea of rolling hills for miles, no neighbors, no hassle, and reasonably priced everything. Houses, produce, and even shoes, all become more affordable the farther South you go, generally, haha.

Though there are a lot of great things about the city, too! For one, there really is always something to do. I would definitely have moments where I felt sort of stuck in Clemson whenever I was antsy to do something fun or adventurous. I felt like my only option was to go hiking (and I didn’t even go that often!). Whenever I feel bored at home in Boston, I hop on the next bus into town! Well, it hasn’t always been that easy, with the pandemic and everything, but during that brief hopeful moment this summer as vaccination rates and COVID-19 positivity rates switched spots, it started to feel something like a city life 😌

I share what things we have done so far that we really enjoyed below!

If you click the images you should see captions πŸ™‚

Boston: the Freedom Trail

  • The Freedom Trail
    • Highly recommend for spring to summer months. Probably fine to do year round tbh, just stay warm β˜ƒοΈ
    • Begins at the Welcome Center of the Public City Garden in Boston Common.
    • It is ~2-3 miles long, and it takes you through all different parts of the city
    • You follow a visible red brick line to every landmark! Don’t worry they are easy to pick out ☺️

Boston: BikeShare

  • BikeRide with BlueBike Share!
    • A 30 minute bike ride costs $3.00 and there’s dozens of drop off points all over the city.
    • You can pretty much follow the river to get to anywhere in the city by bike!

Boston/Cambridge: Kayak the Charles River

  • Kayaking or canoeing along the Charles River
    • You can do a 2-3 hour kayaking trip for as cheap as $25 per person at any one of the popular Charles River Kayak Kiosks along the river banks!
    • Canoeing is even better priced and all of the kiosks offer a range of boating equipment. You can choose from kayaks, canoes, paddleboards, and more (maybe?). The kiosks are located at several river access points so you can choose to paddle through the quieter suburbs toward Newton or dive right into the opening into the Atlantic Ocean near downtown.

That’s basically it for affordable things to do in Boston πŸ˜‚ but I list below a few other places that you might find enjoyable to explore, too:

Cambridge: Fresh Pond

  • Fresh Pond Reservation
    • Lots of trails, parks, and nature in the middle of Cambridge.
View of Little Fresh Pond which is hidden inside the Fresh Pond reservation πŸ˜†

Boston: Harvard Football Stadium

  • Harvard Football Stadium and the Recreational Area there
    • Lots of open fields, tracks, and free recreational stuff. It’s really cool actually it features an outdoor skate park and even an ice skating rink in the winter.

Boston/Cambridge: the Charles River

  • Any recreational spots along the river
    • There is always some cool recreational spots along the river. Where we live now, there are two huge kid parks, two of them are water parks! I’m pretty sure it’s free, too. Just this past weekend I saw the water parks looking like Water Country, USA, with lifeguards and everything, just like in my backyard, it felt like!
    • You just never know what you will find in the city when you explore. At the river near my house, there’s a regular drum circle that plays in the courtyard every weekend. There’s even Herter park, a full on amphitheater that hosts free shows weekly during the summer (yes, even right now!!).
    • One time I even stumbled upon an artist painting the river early one morning on my run πŸ₯Ί it was such a whimsical moment running up among a Bob Ross Bob Rossing it right there in the open. Though I feel bad for the painter hearing me stomping, grunting, panting as I run by. Sorry, dude!

Cambridge: Harvard College Observatory

Oh, yeah! My work! The Harvard & Smithsonian Center for Astrophysics! Why, you might ask?! Well because of the super historical Harvard College Observatory, of course. How can you forget!

Boston: SoWa Open Market

And most recently we went to the SoWa open market in South End for the first time and it was lovely! There’s other more tourist-y things that we did (or tried to do) this summer that we’ve been wanting to do and I’d definitely recommend including the aquarium, whale watching (weather actually cancelled our whale watch event πŸ˜”), festivals like SoWa open market which are happening all times of the year all over the area, and visiting the many beautiful and immaculate college campuses that decorate the city.

Images are all my own and from April — August 2021.

OUR DEEPEST EXPLORATION OF THE UNIVERSE IN X-RAYS

eROSITA is an X-ray space telescope that was launched on July 13, 2019 by an international collaboration, mainly funded by Germany and Russia. The space telescope took its first ever X-ray image three months after orbiting the Earth the following October and has already released some of the first data collected in the first months of operation as well as a schedule confirming the official first data release by December 2022. Most recently, the Astronomy and Astrophysics peer-reviewed science journal has released a special issue including ~35 publications that analyze new eROSITA data. Given the exciting first light and the already big discoveries the telescope has made including the largest supernova remnant ever discovered in X-rays, I thought it would be appropriate to highlight a little bit more about the telescope on my blog! πŸ˜„

The eROSITA telescope flies aboard a large satellite: the Spektrum-RΓΆntgen-Gamma (SRG) space satellite. Along with the primary instrument, eROSITA (extended ROentgen Survey with an Imaging Telescope Array), on the SRG is the Russian ART-XC instrument which can probe higher energy X-rays than eROSITA.

As you have probably guessed, this is an X-ray imaging space telescope. It turns out that the Earth’s atmosphere actually absorbs incoming X-rays (see image below).

This image demonstrates which wavelengths of light can penetrate through Earth’s atmosphere. It is notable that photons with energies greater than ~ultraviolet light are absorbed in the upper layers of the atmosphere. From https://www-xray.ast.cam.ac.uk/xray_introduction/History.html

This is precisely why all astrophysical X-ray instruments are deployed in space including eROSITA.

eROSITA is made up of seven identical and strategically aligned X-ray Mirror Assemblies (MAs) that are situated on an optical bench. Underneath this is the rest of the supporting structure (see the schematic view below), which includes connecting the MAs to the camera assemblies (CAs), i.e. the mirrors will deflect incoming X-rays from its surface in very tiny incident angles that then focus the incoming X-rays onto the cameras (called the grazing incidence angle and is a common practice for designing sensitive X-ray instruments).

A schematic view of the eROSITA X-ray space telescope design. (From http://www.russianspaceweb.com/spektr-rg-erosita.html)

The X-ray “baffles” are used to prevent X-ray photons that are outside of the field of view from contaminating the image being taken at that time. This is particularly important when you need to observe an object that may have bright X-ray sources nearby that can contaminate the X-ray measurements.

The telescope (not SRG, the observatory it is deployed on right now) itself is 1.9 meters wide and 3.2 meters high. For my American readers that is about 6 by 10 feet! πŸ˜€ The completed instrument weighs in at a whopping 808 kg or 1781 pounds!

The Field Of View (FOV) of the full instrument (including all seven cameras) is about 1 degree in diameter. To give you an idea of what portion of the sky eROSITA can see at any given time, the full moon is about 1/2 a degree in the night sky, so eROSITA is able to see an area in the sky that is 2 times larger than the full moon.

This FOV is considerably larger than both of the previously most sensitive X-ray space telescopes, Chandra and XMM-Newton. Further, eROSITA will operate optimally for a specific energy range of X-ray photons. You will almost always see X-ray astronomy use kiloelectron volts to describe the X-ray energies,

1 \text{keV} = 1,000 \text{eV} = 1.6 \times 10^{-12} \text{Joules}

eROSITA, along with Chandra, XMM-Newton, and several other currently operating (and retired) X-ray instruments, can detect X-ray photons between 0.2 keV and 10 keV (see image below, but don’t freak out πŸ˜‰)

From https://www.mpe.mpg.de/455799/instrument

The above plot is showing the field of view averaged effective area in cm squared as a function of energy. You can think of this as the sensitivity of the instrument as a function of energy. Each line corresponds to a different instrument: eROSITA’s seven modules in solid red, Chandra’s ACIS-I setup in green dot-dashed, another Chandra instrument called HRC-I in purple dashed, XMM-Newton’s 3 cameras with the thin filter on, and the previously retired ROSAT PSCPC instrument.

You can see that eROSITA is just about the most sensitive instrument from energies ~0.5keV to ~2keV which is often referred to as the soft X-ray range which just indicates the lower energy range of the X-ray band. Above 2 keV, the sensitivity of eROSITA drops off at a similar rate as the Chandra instruments, while XMM-Newton wins the sensitivity competition at energies greater than about 2keV. With its large field of view in comparison to Chandra and XMM-Newton, eROSITA will make (and has already demonstrated) significant discoveries to X-ray astronomy.

What separates eROSITA from other current missions like Chandra, in addition to its large field of view and sensitivity, is its angular and energy resolution and most of all — the way it will take data. Chandra and XMM-Newton X-ray telescopes are pointing missions. This means the telescope has to position itself for specific observations in varying parts of the sky. The time gets “shared” among thousands of researchers who request for telescope observations every year. eROSITA, on the other hand, is an all-sky survey.

It is the first ever X-ray instrument to survey the entire sky from 0.2-10keV in astronomy HISTORY!

ROSAT was also an all-sky survey, but it only imaged soft X-ray photons, so it didn’t detect X-ray photons with energy more than 2.4keV. ROSAT also had a similar field of view of 2 degrees, but by inspecting the above effective area (i.e. sensitivity) plot, we can see that eROSITA will be a much deeper sky survey, by about 4 times!

To visualize this difference, here is a ROSAT view of the Vela supernova remnant (if you are familiar with my work you have seen the ROSAT image before) in the left panel below compared to the Vela SNR image from eROSITA on the right. I’m unable to find more details about the eROSITA image, but I’m guessing that the colors indicate three energy bands: red is likely the softest of X-rays < 0.6 keV, green is probably “medium” X-rays from 0.6 – 1-ish keV, and blue is likely 1-2.3 keV energies. If this assumption is correct, most of the Vela SNR is dominated by soft and medium X-rays (which is indeed the case, see the ROSAT image on the left lol!). We can also see the smaller overlapping supernova remnant Puppis A is bright in this X-ray range in both images, but that “hard” (higher-energy, see eROSITA image) X-rays dominate the observed emission. Additionally, one can easily spot the Vela central pulsar (lots of hard X-rays there in blue, too!) in the near-center of the eROSITA image, and a third supernova remnant in the lower left corner, visible by only a faint circular blue hue. Neither the central pulsar nor the lower-left supernova remnant is resolved in the ROSAT image. Note: do I see the third supernova remnant’s central compact object in the eROSITA image?!

First light for the eROSITA telescope occurred in mid-October just months after launch

Moreover, eROSITA has already detected 10 times more sources than ROSAT which is about as many as have been discovered by all previous X-ray missions combined. Less than a year after launch, eROSITA has already completed its first all-sky survey, one of eight anticipated full sky surveys.

eROSITA’s first all-sky survey will be released in 2022 (well, the half that the Germans own), reporting already thousands of new sources, most being active galactic nuclei. One of the exciting discoveries includes the largest supernova remnant discovered in X-rays to date which has been nicknamed “Hoinga”. There are a lot of special surprises associated with Hoinga, including its high location with respect to the Galactic plane, an unusual location for supernova remnants to be found.

Straight from the discovery paper: https://arxiv.org/pdf/2102.13449.pdf. The bright blob in the lower right is the Vela SNR (which was first discovered in radio). You can also see the faint but very large (24 degree size) X-ray Antila Loop in the upper left. The colors refer to the X-ray energies: red for 0.3-0.6 keV, green for 0.6-1keV, and blue for 1-2.3 keV.

Hoinga is estimated to have a diameter of about 4.4 degrees. Vela SNR has a diameter of 8 degrees, but it was discovered first in radio, not X-ray.

To conclude, here is a super cool visual graphic about the SRG observatory where eROSITA operates.

I will definitely be on the lookout πŸ‘€ for the first data release, although that means I will have to learn (yet another) new software to clean and analyze the data….. πŸ₯΅ πŸ˜…

A random side note

What I think is extra intriguing about this telescope is the collaboration between Germany and Russia (Just hear me out lol). The terms of the collaboration seem a little unusual. They have defined a German half of the X-ray sky as well as a Russia half of the X-ray sky. Essentially the Western hemisphere of the Galaxy (in Galactic coordinates) is owned by the Germans with unique scientific data exploitation rights and the Eastern hemisphere belongs to the Russians. They have decided to equally share the all-sky surveys, so I suppose the data that has been divided will include individual mission projects i.e. pointed observations for a particular object will have certain proprietary rights depending on its location in the sky. With that being said, only the German half of the sky has been scheduled a public release of data for 2022, and all of the Russian X-ray data and its release schedule is to be determined.

It will be very interesting to see how the data-sharing pans out with this particular method. To be fair, I’m not totally sure if this is a standard practice in international space efforts such as this, but I would be surprised if it is.