# \[4th Zoom Session\] With Astrophysicist Dr. Nimesh Patel **URL:** \ **Category:** Science Friday: Black Holes\ **Created:** [January 28, 2022, 1:59pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524 "2022-01-28T13:59:13Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Mervyn](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/mervyn/32/206_2.png) [@Mervyn](https://group.classcentral.com/u/Mervyn)\ **Post date:** [January 28, 2022, 1:59pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/1 "2022-01-28T13:59:13Z")
[Join our fourth Zoom session](https://us02web.zoom.us/j/86959526287) starting at 2022-01-28T15:00:00Z. _(Feel free to join us 30 minutes earlier to chat and set up your Zoom before we start the session!)_ [Dr. Nimesh](https://pweb.cfa.harvard.edu/people/nimesh-patel) is an astrophysicist and a project engineer working for the Submillimeter Array, since 1994, and the Greenland Telescope, since 2012. His research interests include molecular astrophysics, evolved stars, interstellar medium, star-formation, astrophysical masers, radio interferometry, high-speed analog to digital conversion, antenna pointing, and metrology. He is an instructor for the Harvard undergraduate laboratory astrophysics course, Astronomy 191 and is involved in the development of various educational projects for 21 cm wavelength radio astronomy. He is also a member of the Event Horizon Telescope (EHT) collaboration and participating in the development of the Next Generation EHT. His current work on the Greenland telescope is explored in this [Documentary made by Taiwan TV](https://www.youtube.com/watch?v=KkSSk5zEVC0&ab_channel=%E6%9D%B1%E6%A3%AE%E6%96%B0%E8%81%9ECH51). Dr. Nimesh will be joining us on the zoom session today, so bring your questions and make the best out of this opportunity. See you there, bye! ---
**Author:** ![Fabio](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/fabio/32/177_2.png) [@Fabio](https://group.classcentral.com/u/Fabio)\ **Post date:** [January 28, 2022, 6:36pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/2 "2022-01-28T18:36:19Z")
Session recording: [here.](https://www.classcentral.com/cohort/astro-101-spring-2022/events/63) * * * @Fabio > **[Thule Air Base](https://en.wikipedia.org/wiki/Thule_Air_Base)** > > Thule Air Base (pronounced /tuːliː/ or /tuːleɪ/, Greenlandic: Qaanaaq Mitarfik, Danish: Thule Lufthavn), or Thule Air Base/Pituffik Airport (IATA: THU, ICAO: BGTL), is the United States Space Force's northernmost base, and the northernmost installation of the U.S. Armed Forces, located 750 mi (1,210 km) north of the Arctic Circle and 947 mi (1,524 km) from the North Pole on the northwest coast of the island of Greenland. Thule's arctic environment includes icebergs in North Star Bay, two island... > **[ALMA Observatory](https://almaobservatory.org/en/home/)** > > ALMA Home description @Mervyn [Atacama Large Millimeter Array - Wikipedia](https://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array#:~:text=The%20Atacama%20Large%20Millimeter%2Fsubmillimeter,at%20millimeter%20and%20submillimeter%20wavelengths) @Fabio > **[The Greenland Telescope | Center for Astrophysics](https://pweb.cfa.harvard.edu/facilities-technology/telescopes-instruments/greenland-telescope)** > > The polar regions are challenging environments for humans, but worthwhile for astronomy with their long nights and often-clear skies. The Greenland Telescope is the latest telescope to be placed in the Arctic, as part of the Event Horizon Telescope... -What other types of interference from electronic devices in general? -What kind of astronomical objects can be studied with that technology? @hhliu Wi-Fi is 2.4 and 5 GHz -Standard sampling rates for MP3 etc. are 44.1 kHz and 48 kHz > **[MP3 | Bit rate](https://en.wikipedia.org/wiki/MP3#Bit_rate)** > > Bitrate is the product of the sample rate and number of bits per sample used to encode the music. CD audio is 44100 samples per second. The number of bits per sample also depends on the number of audio channels. CD is stereo and 16 bits per channel. So, multiplying 44100 by 32 gives 1411200—the bitrate of uncompressed CD digital audio. MP3 was designed to encode this 1411 kbit/s data at 320 kbit/s or less. As less complex passages are detected by MP3 algorithms then lower bitrates may be employed... > **[Nyquist–Shannon sampling theorem](https://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem)** > > The Nyquist–Shannon sampling theorem is a theorem in the field of signal processing which serves as a fundamental bridge between continuous-time signals and discrete-time signals. It establishes a sufficient condition for a sample rate that permits a discrete sequence of samples to capture all the information from a continuous-time signal of finite bandwidth. > Strictly speaking, the theorem only applies to a class of mathematical functions having a Fourier transform that is zero outside of a fini... @Fabio That’s a silly question, but can we listen to the universe using the telescope and converting the measumerents to sound? > **[Atomic clock](https://en.wikipedia.org/wiki/Atomic_clock)** > > An atomic clock is a clock that measures time by monitoring the resonant frequency of atoms. It is based on atoms having different energy levels. Electron states in an atom are associated with different energy levels, and in transitions between such states they interact with a very specific frequency of electromagnetic radiation. This phenomenon serves as the basis for the International System of Units' (SI) definition of a second: The second, symbol s, is the SI unit of time. It is defined by... @hhliu I think so! We do that with whale songs, which are too low to hear -The second is defined in terms of atomic oscillations of cesium @Mervyn I want to hear what a black hole sounds like @hhliu Haha not exactly relaxing > **[Hearing the Wave](https://www.ligo.caltech.edu/video/ligo20171016v5)** > > Try listening for the nearly hidden gravitational wave in LIGO's data. > **[Listening to the Big Bang – in high fidelity (audio)](https://www.washington.edu/news/2013/04/04/listening-to-the-big-bang-in-high-fidelity-audio/)** > > A UW physicist has used new satellite data to update his decade-old recreation of the sound of the Big Bang at the birth of the universe. @Mervyn [Betelgeuse - Wikipedia](https://en.wikipedia.org/wiki/Betelgeuse) [Interferometry - Wikipedia](https://en.wikipedia.org/wiki/Interferometry) @hhliu There’s overlap between astrophysics and particle physics now isn’t there? E.g. quantum gravity, early universe - New video from yesterday: [![](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/a/a6af3115b3ca429bf6c29ae92bcf30141cc3f8c1.jpeg "How Does Gravity Escape A Black Hole?") ](https://www.youtube.com/watch?v=cDQZXvplXKA) @Fabio What if we had infrared + radiowaves vision??? How would we see the sky at night??? @hhliu [![](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/a/a99202819489faaf7a8b804e415df0a3473e30b9.jpeg "DIY Telescope") ](https://www.youtube.com/watch?v=pTFOrs5JREw) @sonal Suggestion for next Cohort: [https://www.coursera.org/learn/arctic-introduction-climate](https://www.coursera.org/learn/arctic-introduction-climate) ---
**Author:** ![sonal](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/sonal/32/2112_2.png) [@sonal](https://group.classcentral.com/u/sonal)\ **Post date:** [January 29, 2022, 1:43pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/3 "2022-01-29T13:43:13Z")
Thanks Fabio! I have a question related to sending message. Seems, if I initiate a message, I do not see that! Yesterday I sent a message to you and Mervyn and I do not see my message! Do you see that? It was about another class from Univ from Alberta —— Bugs 101 —- an interesting topic for the Science Friday! Did you get my message?! @Fabio @Mervyn ---
**Author:** ![hhliu](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/hhliu/32/1899_2.png) [@hhliu](https://group.classcentral.com/u/hhliu)\ **Post date:** [January 30, 2022, 6:41am UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/4 "2022-01-30T06:41:13Z")
Some very amateur astrophotography I attempted using an iPhone last November, when Nimesh and Sonal kindly invited me to use their telescope! Our beautiful moon ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/9/919e3843d0c74f251683821d04734a88097f99f5.jpeg) ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/1/190fc222f7982f1fd5e32059feb6d47ec58e5a44.jpeg) ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/7/7009020e04fd9225c3c81c2dfb5fb39390135b58.jpeg) Higher magnification to see craters ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/9/93f7d88781711f65098dcf100fe531e7dca212d6.jpeg) Jupiter and 3 of its 4 Galilean moons ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/3/3d867d0d52303795e1f44922951f380d04451ab1.jpeg) Saturn and its rings ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/c/ca8c585082821c6bb33a751ea1d7ad8742f01ec8.jpeg) ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/c/cc36c9c439eb5c6acdfc8634d5c5a8202701b26e.jpeg) Nimesh and Sonal, the nicest folks 🙂 ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/7/7eac066bd4cba7f5b85acd31e155ed884a4ab7a3.jpeg) ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/1/168bd122fab1b34dee0ae7e0124634c79e0ff88e.jpeg) ![image](https://us1.discourse-cdn.com/flex016/uploads/ccstudygroup/original/2X/8/850fcca8ef80ba1628f0bf99fcf3e90cbc6537ce.jpeg) ---
**Author:** ![sonal](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/sonal/32/2112_2.png) [@sonal](https://group.classcentral.com/u/sonal)\ **Post date:** [January 30, 2022, 11:43pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/5 "2022-01-30T23:43:57Z")
thanks for sharing @hhliu ! @Fabio @Mervyn @dhawal @manoel @pat Haihao has taken these photos with his cellphone through our telescope lens! 🙂 These are photos of Jupiter with its 3 moons, Sturn with its rings, and our moon! We had a great observing night near our home in Cambridge! ---
**Author:** ![pat](https://sea2.discourse-cdn.com/flex016/user_avatar/group.classcentral.com/pat/32/47_2.png) [@pat](https://group.classcentral.com/u/pat)\ **Post date:** [January 30, 2022, 11:58pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/6 "2022-01-30T23:58:53Z")
Amazing results with a telescope and phone! ---
**Author:** ![tanyagarg2606075](https://avatars.discourse-cdn.com/v4/letter/t/f17d59/32.png) [@tanyagarg2606075](https://group.classcentral.com/u/tanyagarg2606075)\ **Post date:** [February 3, 2022, 6:26pm UTC](https://group.classcentral.com/t/4th-zoom-session-with-astrophysicist-dr-nimesh-patel/23524/7 "2022-02-03T18:26:59Z")
Amazing captures! Absolutely love the saturn image with its rings.