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The constellation Orion appears high in the southwestern sky at midnight this week; at the latest meeting of the Warren Astronomical Society, the dimming of the star Betelgeuse was discussed - members mentioned that the star had almost dimmed to the level of the other three major stars in the constellation... which was "just weird."

Orion with dimming Betelgeuse appears high in the southwestern sky at midnight this week. Credit: Stellarium / Bob Trembley.

Here's another comparison showing the dimming of #Betelgeuse - this time shot at 50mm focal length (and cropped in on Orion). At left is a shot from Jan 2019, right is the one from last night. Identical equipment/exposures/apertures etc.

HQ version here: https://t.co/V2PGbskgVI pic.twitter.com/ailwKLfAdn

— Will Gater (@willgater) January 19, 2020

Jupiter makes a return to the southeastern at dawn! Jupiter will appear very low on the horizon this week. Mars continues to appear near the star Antares in the southeastern horizon before dawn - a waning crescent Moon joins the planets on January 23 & 24th.

Venus continues to appear high above the southwestern horizon at dusk this week - a thin waxing crescent Moon joins Venus from Jan. 26-29th.

The Moon is a waning crescent, visible low to the east before sunrise.

The new Moon occurs on Jan. 24th

After Jan. 24th, the Moon will be a waxing crescent, visible toward the southwest in early evening.

The Moon from 2020-01-21 - 2020-01-27. Visualizations by Ernie Wright / NASA's Scientific Visualization Studio.

Moon News

On Feb. 10, join us for a behind-the-scenes look at how we’re developing and advancing the #Artemis missions to the Moon. Learn about astronaut life in space and tour facilities where engineers design and test the Orion spacecraft and Gateway outpost! https://t.co/6a0qRmuYdz pic.twitter.com/rpoTldLg5t

— Johnson Space Center (@NASA_Johnson) January 20, 2020

The Sun has been spot-free for 9 days; coronal holes continue to appear at both poles - the northern hole has reduced in size quite a bit from previous weeks. A small coronal hole appears near the equator; Spaceweather.com says "Solar wind flowing from this minor coronal hole could reach Earth on Jan. 21."

The Sun seen in 193 angstroms (extreme ultraviolet) Jan. 20, 2020:

Several short-lived pillar prominences appeared and vanished over the last couple days:

The Sun seen in 304 angstroms (extreme ultraviolet) Jan. 20, 2020:

Facebook: SolarActivity

Solar Corona

Solar wind speed is 303.5 km/sec (↑), with a density of 3.7 protons/cm³ (↑) at 0955 UT.

Near real-time animation of the corona and solar wind from the Solar & Heliospheric Observatory (SOHO):

Animated LASCO C2 Coronograph showing the solar corona above the Sun's limb (the white circle). Credit: NASA/JPL-Caltech-SOHO

Sun News

#ParkerSolarProbe's measurements of the solar wind reveal a chorus of plasma waves that hold clues to the wind's origins — and scientists have turned some of this data into sound. Listen ⬇️ and read more from @JHUAPL: https://t.co/tPW5TnZrUt https://t.co/1B1xPbQvbd

— NASA Sun & Space (@NASASun) January 15, 2020

Upcoming Earth-asteroid encounters:

Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. Red highlighted entries are asteroids that either pass very close, or very large with high relative velocities to the Earth. Table from SpaceWeather.com

Asteroid News

Jupiter is the shepherd for many, many asteroids - this dance of gravity just amazes me!

Millions of asteroids being shepherded by Jupiter. We call them Trojans and Hildas. https://t.co/FjfmZb9eCz https://t.co/KTQ5HHybKZ pic.twitter.com/ioC7OAJjvI

— Chris Hadfield (@Cmdr_Hadfield) January 16, 2020

On Jan. 20, 2020, the NASA All Sky Fireball Network reported 13 fireballs. 
(13 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). From: Spaceweather.com

Fireball News

Estoy aquí admirando la vista, tomando fotos como de costumbre y tiro una foto, thank God que fue Live Photo y capture este meteorito ☄️. pic.twitter.com/UREFQVvARQ

— LOUI 📸 (@LouisVtweeter) January 17, 2020

Satellite loop appears to show the flash of the meteorite seen in Puerto Rico this evening! ☄️ @StormHour pic.twitter.com/Mepq8UBUVG

— Collin Gross (@CollinGrossWx) January 17, 2020

Position of the planets and a couple spacecraft in the inner solar system - the Parker Solar Probe has re-crossed the orbit of Mercury.

Position of the planets and a couple spacecraft in the inner solar system, 2020-01-21. Credit: NASA Eyes on the Solar System / Bob Trembley.

Position of the planets in the middle solar system - the Earth's orbit is bringing it around the Sun, and Jupiter is coming back into view at dawn.

Position of the planets in the middle solar system, 2020-01-21. Credit: NASA Eyes on the Solar System / Bob Trembley.

Position of the planets in the outer solar system - the orbit of transneptunian object (174567) Varda-Ilmarë is highlighted:

Outer Solar System 2020-01-21 - Orbit of binary transneptunian object 174567 Varda-Ilmarë is highlighted. Credit: SpaceEngine / Bob Trembley.

(174567) Varda-Ilmarë

174567 Varda (provisional designation 2003 MW₁₂) is a binary trans-Neptunian object of the resonant hot classical population of the Kuiper belt, located in the outermost region of the Solar System. Its moon, Ilmarë, was discovered in 2009.

Brown estimates that, with an absolute magnitude of 3.5 and a calculated diameter of approximately 700–800 kilometers (430–500 miles), it is likely a dwarf planet. However, Grundy et al. argue that objects such as Varda, in the size range of 400–1000 km, with albedos less than ≈0.2 and densities of ≈1.2 g/cm³ or less, have likely never compressed into fully solid bodies, let alone differentiated, and so are highly unlikely to be dwarf planets.

...

Varda has at least one satellite, Ilmarë (or Varda I), which was discovered in 2009. It is estimated to be about 350 km in diameter (about 50% that of its primary), constituting 8% of the system mass, or 2×10¹⁹ kg, assuming its density and albedo the same as that of Varda.

The Varda–Ilmarë system is tightly bound, with a semimajor axis of 4809±39 km (about 12 Varda radii) and an orbital period of 5.75 days. - Wikipedia

174567 Varda seen from above Ilmarë - the system's barycenter is the gray diamond, and the orbit of Varda around that barycenter is shown in red. Credit: SpaceEngine / Bob Trembley.

NASA's Interactive Real-Time Web-based Orrery:

SpaceX Dragon In-Flight Abort Test

Test complete! Today, @SpaceX completed its In-Flight Abort Test designed to show the #CrewDragon spacecraft’s capability to safely separate from the rocket in the unlikely event of an inflight emergency: https://t.co/j7v2y8svOk pic.twitter.com/VbKh9E2BAQ

— NASA (@NASA) January 19, 2020

OSIRIS-REx Asteroid Sample Return Mission

On Tuesday, Jan 21, I’ll fly closer to site Nightingale than ever before.
Time to start preparing for #TAG2020
Let’s do this 😎 pic.twitter.com/ZyjBIyeUsG

— NASA's OSIRIS-REx (@OSIRISREx) January 17, 2020

International Space Station

At 1:33pm EST, @Astro_Jessica and @Astro_Christina concluded today's spacewalk. After working 6 hours and 58 minutes the two successfully completed the battery upgrade for one channel on one pair of the station’s solar arrays. #AskNASA | Read more... https://t.co/GQfO9zyIGP pic.twitter.com/e3mHSeM8l3

— Intl. Space Station (@Space_Station) January 20, 2020

Transiting Exoplanet Survey Satellite (TESS)

The final speaker of the #AAS235 @NASA_TESS splinter session is Eliza Kempton. She highlighted how many of the exoplanets being discovered by TESS are prime targets for @NASAWebb - JWST can be used to reveal the properties of the atmospheres of exoplanets! pic.twitter.com/e3r199OeWn

— NASA_TESS (@NASA_TESS) January 7, 2020

Hubble Space Telescope

ESA/Hubble #Flashback: Within this galaxy, NGC 4993, Hubble discovered the first visual counterpart of a gravitational wave event — the merger of two neutron stars.

Credit: @NASA / @ESA , Digitized Sky Survey 2 https://t.co/mQ290mRWvA pic.twitter.com/9EanqATBdQ

— HUBBLE (@HUBBLE_space) January 21, 2020

Climate

LIVE: NASA and @NOAA climate experts discuss the annual global temperatures analysis for 2019 in a teleconference: https://t.co/PWJkcuQ2Jt
Earth's global surface temperatures in 2019 were the second warmest since modern recordkeeping began in 1880: https://t.co/ZRrydb1PiR pic.twitter.com/aA4kbtaWJU

— NASA (@NASA) January 15, 2020

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.

Dr. T.K. Lawless County Park has been designated as an IDSPark! Parks Director, Scott Wyman says, “Through the parks, we've always been able to say that we are stewards of the land, but I’m very proud to say that now, we are stewards of the land & the sky"https://t.co/yopVKWc57Z

— IDA Dark-Sky (@IDADarkSky) January 15, 2020

New class of stellar objects: G-objects

The newly detected population of G-objects adds more mystery to an already fascinating group of objects in orbit around our supermassive black hole! This animation shows the orbits of the G-objects (purple), young stars (green), and old stars (orange).@GalacticCtrGrp & AVL/NCSA pic.twitter.com/gRDUrt6sdH

— Tuan Do (@quantumpenguin) January 17, 2020

Astronomers have discovered a mysterious new class of objects at the heart of the Milky Way, unlike anything else found previously in our galaxy. The objects “look like gas but behave like stars,” according to senior researcher Andrea Ghez, as they start off small and compact but are stretched to a larger size when they approach the supermassive black hole in the center of the galaxy.

The researchers believe these objects could teach us about the evolution of stars and what happens to celestial bodies in environments of extreme gravity.

The puzzle began in 2005 when astronomers identified an object near the center of our galaxy called G1, which seemed to be orbiting around the supermassive black hole there in a strange way. In following years, five more objects numbered G2 to G6 were discovered. At first, these objects were thought to be clouds of gas. But one odd thing researchers noticed was that when the object G2 came very close to the event horizon of the black hole, it wasn’t torn apart in the way they would have expected. Instead, it initially stretched out, before rebounding back toward its original state. - reddit

Artist's representation of what G Objects look like. Credit: NASA, UCLA Galactic Group, Others.

The Local Stellar Neighborhood

Continuing with my visual tour of nearby stars and their systems, we travel to the Alpha Centauri binary system.

Stars up to ten light-years from the Sun. Credit: SpaceEngine / Bob Trembley

Alpha Centauri A & B

Alpha Centauri (Latinized from α Centauri, abbreviated Alpha Cen or α Cen) is the closest star system and closest planetary system to Earth's Solar System at 4.37 light-years (1.34 parsec) from the Sun. It is a triple star system, consisting of three stars: α Centauri A (officially Rigil Kentaurus), α Centauri B (officially Toliman), and α Centauri C (officially Proxima Centauri).

Alpha Centauri A and B are Sun-like stars (Class G and K), and together they form the binary star Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27, forming the brightest star in the southern constellation of Centaurus and the third-brightest in the night sky, outshone only by Sirius and Canopus.

Alpha Centauri A has 1.1 times the mass and 1.519 times the luminosity of the Sun, while Alpha Centauri B is smaller and cooler, at 0.907 times the Sun's mass and 0.445 times its luminosity. The pair orbit around a common centre with an orbital period of 79.91 years. Their elliptical orbit is eccentric, so that the distance between A and B varies from 35.6 AU (astronomical units), or about the distance between Pluto and the Sun, to 11.2 AU, or about the distance between Saturn and the Sun. - Wikipedia

Orbits of Alpha Centauri A (red) & B (blue). Credit: SpaceEngine / Bob Trembley.

To date, no planets have been detected orbiting either Alpha Centauri A or B.

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. I maintain the unofficial NASA Eyes Facebook page.
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.
Universe Sandbox: a space simulator that merges real-time gravity, climate, collision, and material interactions to reveal the beauty of our universe and the fragility of our planet. Includes VR support.
SpaceEngine: a free 3D Universe Simulator for Windows. Steam version with VR support available.

Section header image credits:
The Sky - Stellarium / Bob Trembley
Observing Target - Turn Left at Orion / M. Skirvin
The Moon - NASA/JPL-Caltech
The Sun - NASA/JPL-Caltech
Asteroids - NASA/JPL-Caltech
Fireballs - Credited to YouTube
Comets - Comet P/Halley, March 8, 1986, W. Liller
The Solar System - NASA Eyes on the Solar System / Bob Trembley
Spacecraft News - NASA Eyes on the Solar System / Bob Trembley
Exoplanets - Space Engine / Bob Trembley
Light Pollution - NASA's Black Marble
The Universe - Universe Today