Merry Christmas everyone! Sorry this post is a tad late, I’ve been a bit preoccupied the last couple days…
The multi-planet conjunction in the eastern predawn sky continues this week.
Mercury, Jupiter, Venus and Spica in the southeastern predawn sky – Dec. 26, 2018. Credit: Stellarium / Bob Trembley – using the new “Sky and Telescope” starlore set.Mars remains high in southern sky after sunset all week; Mars is now at magnitude 0.39, down significantly from -2.78 during opposition at the end July 2018.
Mars remains high in the southern sky after sunset – Dec. 26, 2018. Credit: Stellarium / Bob Trembley – using the new “Sky and Telescope” starlore set.The stars Altair and Vega battle for the title of “evening star” in the western sky at dusk.
Altair and Vega in the western sky after sunset – Dec. 26, 2018. Credit: Stellarium / Bob Trembley – using the new “Sky and Telescope” starlore set.The Moon appears in the constellation Leo at midnight Dec. 27th.
The Moon rises in the east shortly before midnight – Dec. 27, 2018. Credit: Stellarium / Bob Trembley – using the new “Sky and Telescope” starlore set.Observing Target: M64 – The Black Eye Galaxy
M64 is a spiral galaxy located 17 million light years away in the constellation of Coma Berenices.
M64 imaged using amateur telescope. Credit: Jeffjnet (http://jeffjastro.com) / CC BY-SA 3.0“A collision of two galaxies has left a merged star system with an unusual appearance as well as bizarre internal motions. Messier 64 (M64) has a spectacular dark band of absorbing dust in front of the galaxy’s bright nucleus, giving rise to its nicknames of the “Black Eye” or “Evil Eye” galaxy.
Fine details of the dark band are revealed in this image of the central portion of M64 obtained with the Hubble Space Telescope. M64 is well known among amateur astronomers because of its appearance in small telescopes. It was first cataloged in the 18th century by the French astronomer Messier. Located in the northern constellation Coma Berenices, M64 resides roughly 17 million light-years from Earth.
At first glance, M64 appears to be a fairly normal pinwheel-shaped spiral galaxy. As in the majority of galaxies, all of the stars in M64 are rotating in the same direction, clockwise as seen in the Hubble image. However, detailed studies in the 1990’s led to the remarkable discovery that the interstellar gas in the outer regions of M64 rotates in the opposite direction from the gas and stars in the inner regions.
Active formation of new stars is occurring in the shear region where the oppositely rotating gases collide, are compressed, and contract. Particularly noticeable in the image are hot, blue young stars that have just formed, along with pink clouds of glowing hydrogen gas that fluoresce when exposed to ultraviolet light from newly formed stars.
Astronomers believe that the oppositely rotating gas arose when M64 absorbed a satellite galaxy that collided with it, perhaps more than one billion years ago. This small galaxy has now been almost completely destroyed, but signs of the collision persist in the backward motion of gas at the outer edge of M64.
This image of M64 was taken with Hubble’s Wide Field Planetary Camera 2 (WFPC2). The color image is a composite prepared by the Hubble Heritage Team from pictures taken through four different color filters. These filters isolate blue and near-infrared light, along with red light emitted by hydrogen atoms and green light from Strömgren y.” – HubbleSite
M64 from the Hubble Space Telescope. Credits: NASA and The Hubble Heritage Team (AURA/STScI);Acknowledgment: S. Smartt (Institute of Astronomy) and D. Richstone (U. Michigan)
Location of M64. Credit: Stellarium / Bob Trembley.The Moon
The Moon is a waning gibbous – rising after sunset, high in the sky after midnight, visible to the southwest after sunrise. The third quarter Moon occurs on Dec. 29th – rising around midnight, visible to the south after sunrise. After the 29th, the Moon will be a waning crescent – low to the east before sunrise.
The Moon from Dec. 26, 2018 – Jan. 1, 2019. Visualizations by Ernie Wright.
Labeled Zoom-in of the Moon, Dec. 29, 2018. Visualizations by Ernie Wright.The Sun
The Sun has been spot-free for 9 days now. The large coronal hole at the northern pole has spawned a tendril extending down to the equator, and the southern coronal hole remains wide open. A region of coronal loop activity is rotating into view – this region is visible in both videos below.
SpaceWeather.com says “A northern hole in the sun’s atmosphere is turning to face Earth and it is spewing a stream of solar wind in our direction. Estimated time of arrival: Dec. 28th. Arctic sky watchers should be alert for auroras in the nights after Christmas.”
Lots of prominence activity over the last couple days – especially in the lower right of the video below.
The solar wind speed is 411.4 km/sec (↓), with a density of 6.5 protons/cm3 (↑).
Animated LASCO C2 Coronograph showing the solar corona above the Sun’s limb (the white circle).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.
Asteroids
Upcoming Earth-asteroid encounters:
| Asteroid |
Date(UT)
|
Miss Distance
|
Velocity (km/s)
|
Diameter (m)
|
| 2018 XC4 |
2018-Dec-21
|
1.6 LD
|
7.8
|
21
|
| 2017 XQ60 |
2018-Dec-21
|
11.3 LD
|
15.6
|
47
|
| 163899 |
2018-Dec-22
|
7.4 LD
|
6.2
|
1232
|
| 418849 |
2018-Dec-23
|
16.6 LD
|
17.6
|
269
|
| 2018 XN5 |
2018-Dec-24
|
3 LD
|
6.4
|
30
|
| 2018 XE4 |
2018-Dec-26
|
5.4 LD
|
9.4
|
18
|
| 2014 AD16 |
2019-Jan-04
|
12.9 LD
|
9.4
|
12
|
| 2018 XO4 |
2019-Jan-06
|
7.8 LD
|
4
|
31
|
| 2016 AZ8 |
2019-Jan-07
|
11.6 LD
|
9.1
|
224
|
| 2013 YM2 |
2019-Jan-09
|
7.3 LD
|
4.3
|
20
|
| 2018 XN |
2019-Jan-14
|
11.9 LD
|
5.6
|
59
|
| 2013 CW32 |
2019-Jan-29
|
13.9 LD
|
16.4
|
148
|
| 2013 RV9 |
2019-Feb-06
|
17.9 LD
|
5.9
|
68
|
| 2017 PV25 |
2019-Feb-12
|
7.3 LD
|
6.1
|
43
|
| 455176 |
2019-Feb-20
|
19.2 LD
|
26.5
|
269
|
| 2016 CO246 |
2019-Feb-22
|
15.8 LD
|
5.5
|
23
|
Notes: LD means “Lunar Distance.” 1 LD = 384,401 km, the distance between Earth and the Moon. Table from SpaceWeather.com
Near-Earth objects (NEOs) discovered this month: 118, this year: 1962, all time: 19362.
Potentially hazardous asteroids: 1947 (as of Dec. 26, 2018 – up from 1936)
Minor Planets discovered: 789,069 (as of Oct. 30, 2018)
Fireballs
On Dec. 25, 2018, the NASA All Sky Fireball Network reported 14 fireballs.
(11 sporadics, 1 December Leonis Minorid, 1 December Hydrid, 1 alpha Hydrid)
In this diagram of the inner solar system, all of the fireball orbits from Dec. 25, 2018 intersect at a single point–Earth. Source: Spaceweather.comComets
Social media continues to be flooded with images of Comet 46P/Wirtanen.
The Solar System
This is the position of the planets and a couple spacecraft in the solar system.
Position of the planets in the inner solar system, Dec. 26, 2018. Credit: NASA Eyes on the Solar System / Bob Trembley.
Position of the planets in the middle solar system, Dec. 26, 2018. Credit: NASA Eyes on the Solar System / Bob Trembley.
Position of the planets in the outer solar system, Dec. 26, 2018. Credit: NASA Eyes on the Solar System / Bob Trembley.Spacecraft
OSIRIS-REx – Preparing to orbit asteroid Bennu
Mars InSight – Deployed a seismometer on the surface of Mars
New Horizons – On final approach to 2014 MU69 New Year’s flyby
No change from last week.
-Data from the NASA Exoplanet Archive
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.
NOTE: Stellarium v.0.18.3 was released on Dec. 22. 2019 – extensive release notes here.
July 20, 2019 is the 50th Anniversary of the Apollo 11 landing on the Moon.
2018 is NASA’s 60th Anniversary!
