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In the Sky this Week – September 21, 2021

By Robert Trembley  |  21 Sep 2021  |  Sacred Space Astronomy

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This entry is part 209 of 253 in the series In the Sky This Week

Feature|The Sky|The Moon|The Sun|Asteroids|Fireballs|The Solar System|Spacecraft News|Exoplanets|Aurora|Light Pollution|The Universe|

Astronomy at the Beach!

The State of Michigan is incredibly lucky to have so many active astronomy clubs and amateur astronomers. Each September, the Great Lakes Association of Astronomy Clubs hosts the Astronomy at the Beach event – this will be their 25th year. This year the event will be held both Friday and Saturday Sept. 24 & 25.

Due to COVID, the event is being held online again this year; not a single astronomer wanted there to be any chance that the event or their equipment would be a vector for the spreading the virus – especially to children, who typically make up a good percentage of the attendees.

The original idea was to “only do telescope live-streaming,” but the Ford Amateur Astronomy Club (FAAC) decided to host various presentations on their Zoom channel all evening. This pushed ME over the edge, and I scheduled a presentation each evening too! We’ve even arranged to live-stream southern hemisphere skies!

Fri: Mission to Mars in KSP

Sat: Tour of the Solar System in SpaceEngine

Both Friday and Saturday, the FAAC will be hosting an “Astro Hangout” with a bunch of Michigan astronomers – including myself! Come and join us!

The Sky - In the Sky

Jupiter and Saturn continue to appear in the southeastern sky after sunset all week.

Southeastern sky after sunset
Jupiter and Saturn appear in the southeastern sky after sunset all week… again. Credit: Bob Trembley / Stellarium.

Venus appears low above the southwestern horizon after sunset throughout December.

Southwestern sky after sunset
Venus appear low above the southwestern horizon after sunset all week. Credit: Bob Trembley / Stellarium.

The Moon appears in the eastern sky with the Pleiades star cluster, and the star Aldebaran at midnight on Sept. 25th.

Eastern sky at midnight
The Moon in the eastern sky with the Pleiades and Aldebaran at midnight on Sept. 25th. Credit: Bob Trembley / Stellarium.

The Moon appears near the star Aldebaran in the eastern sky shortly after midnight on Sept. 27th.

Eastern sky after midnight
The Moon near Aldebaran in the eastern sky during the early morning of Sept. 27th. Credit: Bob Trembley / Stellarium.

The sky shortly after sunset this week:

The Sky
The Sky on Sept. 21st at 9:00 pm. Credit: Bob Trembley / Stellarium.
The Moon - In the Sky
  • The Moon is a Waning Gibbous – rising after sunset, visible high in the sky after midnight, and visible to the southwest after sunrise.
  • The Moon is NOT a Waning Gibbon – I recently heard that a teacher actually used that phrase…
  • The Third Quarter Moon occurs on Sept. 28th – rising around midnight, and is visible to the south after sunrise.
Moon
The Moon from Sept. 21-27, 2021. Visualizations by Ernie Wright / NASA’s Scientific Visualization Studio.

If you click on the Moon image above, or click this link, you will go to NASA’s Moon Phase and Libration, 2021 page – it will show you what the Moon looks like right now. If you click the image on that page, you will download a high-rez TIFF image annotated with the names of prominent features – helpful for logging your lunar observations!

Moon News:

Forget “Snakes on a Plane” – how about “VIPERS on Luna!”

📣 Just in! We’ve selected a landing site for VIPER. The water-hunting rover will land west of Nobile crater near the Moon’s South Pole. VIPER is a robotic scout to identify and study resources for future human exploration. https://t.co/0Ui0NowtGo pic.twitter.com/xCVsr6HOjg

— NASA Moon (@NASAMoon) September 20, 2021

The Sun - In the Sky

The Sun has 3 sunspots – one of them is pretty large!

SpaceWeather.com says: “Sunspot AR2871 is crackling with C-class solar flares.” They also report: “A dark filament of magnetism exploded away from the sun’s southern hemisphere on Sept. 19th. Watch the movie. NOAA analysts say the debris could reach Earth on Sept. 23rd in the form of a weak CME. A likely glancing blow could spark minor G1-class geomagnetic storms.”

The Sun on September 21, 2021. Credit: SDO/HMI

The Sun seen in 193 angstroms on September 20th.

WOW! Super active Sun this week! Both north and south coronal holes are open, and there’s a couple big ones right smack in the center of the Sun’s face. All the sunspots are obvious from their coronal loops, and there’s something in the upper left rotating into view.

https://sdo.gsfc.nasa.gov/assets/img/dailymov/2021/09/20/20210920_1024_0193.mp4

The Sun seen in 304 angstroms on September 20th.

Prominences, filaments and flares, oh my!

https://sdo.gsfc.nasa.gov/assets/img/dailymov/2021/09/20/20210920_1024_0304.mp4
Videos courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
You can view the Sun in near real-time, in multiple frequencies here: SDO-The Sun Now.
You can create your own time-lapse movies of the Sun here: AIA/HMI Browse Data.
You can browse all the SDO images of the Sun from 2010 to the present here: Browse SDO archive.

Amateur Solar Astrophotography

The Sun – Sept. 21, 2021. Credit: Gianfranco Meregalli

Solar Corona

Solar wind speed is 336.8 km/sec ▼ with a density of 7.7 protons/cm3 ▲ at 1420 UT.

Sun
SOHO LASCO C2 Latest Image

Click here to see a near real-time animation of the corona and solar wind from the Solar & Heliospheric Observatory (SOHO).

Sun News:

Can you help @NASA unlock the secrets of the Sun? 🔓☀️

That’s one of more than two dozen challenges in this year’s #SpaceApps, which puts space data in your hands for innovation. Explore the challenges & register now for the Oct. 2-3 event: https://t.co/IcPWHDDSTA pic.twitter.com/34Sxxs6eQ7

— NASA Sun & Space (@NASASun) September 20, 2021

Asteroids - In the Sky
  • Near-Earth Objects (NEOs) discovered this month: 257, this year: 2062 (+64), all time: 26,898 (+65)
  • Potentially Hazardous Asteroids (PHAs): 2207 (+2 updated 2021-09-14)
  • Total Minor Planets discovered (NASA): 1,113,527 (updated 2021-08-17) – still not been updated for weeks.
  • Total Minor Planets discovered (MPC): 1,116,788 (-28, updated 2021-09-21) – after weeks of not being updated, this number goes down!

Upcoming Earth-asteroid encounters:

Asteroid Date(UT) Miss Distance Velocity (km/s) Diameter (m)
2021 RV19 2021-Sep-21 7.7 LD 9.5 20
2021 RX9 2021-Sep-21 8.3 LD 14.6 23
2021 RP9 2021-Sep-21 15.8 LD 18 46
2021 RN16 2021-Sep-21 1.3 LD 9.7 7
2021 SO 2021-Sep-22 15.2 LD 5.7 30
2021 RS 2021-Sep-22 18.6 LD 3.4 37
2021 NY1 2021-Sep-22 3.9 LD 9.4 177
2021 SK 2021-Sep-24 13.3 LD 12.8 30
2021 QV6 2021-Sep-24 9.3 LD 13.1 96
2019 SF6 2021-Sep-26 16.4 LD 8.6 20
2021 RP10 2021-Sep-27 9.7 LD 16.4 41
2021 RG19 2021-Sep-28 2.2 LD 15.3 35
2021 RM5 2021-Sep-30 10.9 LD 4.1 19
2021 RF2 2021-Sep-30 7.3 LD 5.4 25
2021 RP12 2021-Oct-06 5.1 LD 9.5 40
1998 SD9 2021-Oct-06 10.6 LD 10.8 59
2015 TQ21 2021-Oct-07 10.7 LD 20.7 12
2021 RF5 2021-Oct-10 19.9 LD 8.8 42
2021 QF5 2021-Oct-11 15.4 LD 7.1 51
2019 SE5 2021-Oct-11 16.3 LD 6.6 16
2020 TH6 2021-Oct-19 7.3 LD 5.9 6
1996 VB3 2021-Oct-20 8.8 LD 15.3 135
2021 RE10 2021-Oct-21 15.5 LD 5.1 54
2017 SJ20 2021-Oct-25 18.7 LD 15.7 123
2019 UW6 2021-Oct-26 8 LD 11.1 17
2009 WY7 2021-Nov-02 19.2 LD 14.7 54
2017 TS3 2021-Nov-02 13.9 LD 9.9 135
2005 VL1 2021-Nov-04 17 LD 5.2 18
2020 KA 2021-Nov-06 14.9 LD 4.8 11
2019 XS 2021-Nov-09 1.5 LD 10.7 65
2017 WG14 2021-Nov-10 18.6 LD 11.6 45
2004 UE 2021-Nov-13 11.1 LD 13.2 178
2016 VR 2021-Nov-15 8 LD 8.7 20
2010 VK139 2021-Nov-15 6.4 LD 13.9 65
2019 VL5 2021-Nov-15 8.6 LD 8 23
Notes: LD means “Lunar Distance.” 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.

Asteroid News:

Analysis based on data from the Hayabusa-2 mission

The surface of #asteroid Ryugu reflects and scatters light in ways consistent with laboratory-studied carbonaceous chondrite meteorites. View this new analysis based on data from the #Hayabusa-2 mission in an article posted on @physorg_com:https://t.co/G8yl5RsfpR pic.twitter.com/mCkyFjUTIf

— Asteroid Day ☄ (@AsteroidDay) September 21, 2021

Tunguska-like airburst may have destroyed a Bronze-age city 3,700 years ago!

Fireballs - In the Sky

On September 20, 2021, the NASA All Sky Fireball Network reported 5 fireballs!
(5 sporadics)

In this diagram of the inner solar system, all of the fireball orbits intersect at a single point–Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). Credit: SpaceWeather.com

Fireball News:

https://twitter.com/UKMeteorNetwork/status/1439140684288647172

If you see a bright meteor or a fireball, please REPORT IT to the American Meteor Society and the International Meteor Organization!

The Solar System - In the Sky

Position of the planets & several spacecraft in the inner solar system on September 21th:

Inner Solar System
Top-down view of the inner solar system on September 21, 2021. Credit: Bob Trembley / NASA Eyes on the Solar System

Position of the planets in the middle solar system:

Middle Solar System
Top-down view of the middle solar system on September 21, 2021. Credit: Bob Trembley / NASA Eyes on the Solar System

Position of the planets in the outer solar system:

Outer Solar System
Top-down view of the outer solar system on September 21, 2021. Credit: Bob Trembley / NASA Eyes on the Solar System

Solar System News

This conversation caught my eye

Great graphic from Desch+2018 showing 1 interpretation of where and when meteorites forming – has Jupiter forming around 3au and migrating out.
t=0 comes from lead-lead dating of oldest CAIs – 4567.30 ± 0.16 Myr ago (Connelly+2012: 10.1126/science.1226919)https://t.co/awnjo4qAU9

— Eric Mamajek (@EricMamajek) September 21, 2021

Spacecraft News - In the Sky

Insight Lander

1,000 sols (days) on Mars today – some eventful, and others quite peaceful – as I listen closely to the heartbeat of Mars. And with the seasons changing, I’m starting to see a little more sunlight and power. Sending warm vibes to you, wherever you are. ☀️ pic.twitter.com/h9cpoERz8J

— NASA InSight (@NASAInSight) September 18, 2021

NASA's Perseverance Mars Rover

Where a human geologist would use a rock hammer to crack a rock open and look inside, I’ve got my abrasion tool to make little windows into Mars history for me. Here’s what my latest rock target looks like inside.

More images: https://t.co/Ex1QDo3eC2 pic.twitter.com/Y7KJljxBvU

— NASA's Perseverance Mars Rover (@NASAPersevere) September 20, 2021

International Space Station -vs- Lunar Gateway

How does the Gateway compare in size to the @Space_Station? The Gateway is about one-sixth the size of the ISS and can support four crew members for 30 – 60 days while @NASA_Orion spacecraft is docked. pic.twitter.com/SPM1K1K5Gx

— Gateway Lunar Space Station (@NASA_Gateway) September 21, 2021

International Space Station

Expedition 65 is kicking off the week with a host of space biology and robotics activities aboard station today. https://t.co/54MSX1ab7w

— International Space Station (@Space_Station) September 20, 2021

HiRISE - Beautiful Mars

Mars to Music!

Landsat Program

Learn about the #Landsat 9 Mission

Learn about the #Landsat 9 Mission milestones, important mission locations, the commissioning and operations phases, and when Landsat 9 data will become publicly available through the @USGS.

Read more in this interactive story map:
👉https://t.co/9WE1S9jkVH #Countdowntolaunch pic.twitter.com/uwsj3qb0bJ

— USGS Landsat (@USGSLandsat) September 20, 2021

Climate

Bon voyage! NASA sent two wind-propelled, solar-powered robots called Saildrones to study changing ocean temperatures in the Arctic and validate satellite measurements of the ocean taken from space. 🌊🛰#EarthExpeditions https://t.co/Lwn4qRtf3E pic.twitter.com/9DUPPSri8I

— NASA Earth (@NASAEarth) September 17, 2021

See a list of current NASA missions here: https://www.jpl.nasa.gov/missions?mission_status=current

Exoplanets - In the Sky

ex·o·plan·et /ˈeksōˌplanət/, noun: a planet orbiting a star other than the Sun.

All Exoplanets 4516
Confirmed Planets Discovered by Kepler 2402
Kepler Project Candidates Yet To Be Confirmed 2361
Confirmed Planets Discovered by K2 463
K2 Candidates Yet To Be Confirmed 889
Confirmed Planets Discovered by TESS 155
TESS Project Candidates Integrated into Archive (2021-09-18 13:00:02) 4511
Current date TESS Project Candidates at ExoFOP 4511
TESS Candidates Yet To Be Confirmed 3062 (-5)

Data from the NASA Exoplanet Archive
* Confirmed Planets Discovered by TESS refers to the number planets that have been published in the refereed astronomical literature.
* TESS Project Candidates refers to the total number of transit-like events that appear to be astrophysical in origin, including false positives as identified by the TESS Project.
* TESS Project Candidates Yet To Be Confirmed refers to the number of TESS Project Candidates that have not yet been dispositioned as a Confirmed Planet or False Positive.

Exoplanet News:

Reminder: Applications are due by 8pm PDT this Thursday, Sept. 23. In addition to monthly presentations, #ExoExplorers activities include weekly tag-ups, group discussions with prominent exoplanet scientists, training sessions, and cohort-driven activities pertaining to #DEIA. https://t.co/w2gVaGTPvB

— NExScI: Exoplanet Science Institute Caltech IPAC (@NExScI_IPAC) September 20, 2021

Aurora - In the Sky

SpaceWeather.com Realtime Aurora Gallery: https://spaceweathergallery.com/aurora_gallery.html

Light Pollution - In the Sky

New research shows that #lightpollution has increased by at least 49% over 25 years globally. This figure only accounts for light visible via satellites. So, the true increase may be much higher – up to 270% globally, & 400% in some regions.

Learn more: https://t.co/uZ7rYLz7ru

— DarkSky International (@IDADarkSky) September 14, 2021

  • Visit an International Dark Sky Park: https://www.darksky.org/our-work/conservation/idsp/parks/
  • If you live in Michigan, visit the Michigan Dark Skies site: https://sites.lsa.umich.edu/darkskies/
The Universe - In the Sky

Education and STEM

World Space Week celebrates Dorothy Johnson Vaughan

World Space Week 2021: Oct. 4-10

Today we celebrate Dorothy Johnson Vaughan (20 September 1910 – 10 November 2008) an American mathematician and human computer who worked at @NASA_Langley. In 1949, she became #NASA's first African-African manager. 👩🏾🖥🌠 pic.twitter.com/eFoT2NO5JE

— World Space Week (@WorldSpaceWeek) September 20, 2021

Solar System Ambassador Applications Still Open!

📢 Calling all space enthusiasts across the US!✨

Applications for Solar System Ambassadors are open! Those in Delaware, Mississippi, Nevada, North Dakota, South Dakota, D.C. & U.S. territories are especially encouraged to apply.

📅 Apply by Sept. 30! https://t.co/ENc7tTIddv pic.twitter.com/RbPHn8TjjC

— NASA STEM (@NASASTEM) September 21, 2021

Astronomy at the Beach

Michigan astronomers can’t wait to be able to host the Astronomy at the Beach event live and in-person again – join us online this weekend!

Setting up for Astronomy at the Beach – I’m on the left. Credit: Doug Bock

What I was listening to while I was writing this:

https://open.spotify.com/track/2gQsUHVFY4tpXc3AFU2mcS?si=e8892d5b02ba4660
https://open.spotify.com/track/21j1PsCiTaO8ZW88UZrh3A?si=880db61a48cf4b61

Software Apps used for this post:

NASA Eyes on the Solar System: an immersive 3D solar system and space mission simulator – free for the PC /MAC.
SpaceEngine: a free 3D Universe Simulator for Windows. Steam version with VR support available.
Stellarium: a free open source planetarium app for PC/MAC/Linux. It’s a great tool for planning observing sessions. A web-based version of Stellarium is also available.

Feature|The Sky|The Moon|The Sun|Asteroids|Fireballs|The Solar System|Spacecraft News|Exoplanets|Aurora|Light Pollution|The Universe|

Stay safe, be well, and look up!

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