Saturn and Jupiter continue to be excellent observing targets in the southern sky after sunset; this last weekend. The Warren Astronomical Society hosted a boatload of girl and boy scouts at their Stargate Observatory this last weekend – I was with the girl scouts before dusk showing them a virtual reality fly-over of Saturn, another member was talking to the girls about meteorites.
Saturn and Jupiter in the southwestern sky after sunset on Oct. 22, 2019 – the teapot asterism in the constellation Sagittarius is highlighted. Credit: Stellarium / Bob TrembleyMars appears low in the eastern sky just before sunrise.
The planet Mars low on the eastern horizon before dawn. Credit: Stellarium / Bob TrembleyThe Moon passes through the constellations Cancer and Leo in the mornings of Oct. 22-24th.
The Moon passing through the constellations Cancer and Leo from Oct. 22-24, 2019. Credit: Stellarium / Bob TrembleyA very VERY thin waning crescent Moon appears near to Mars above the eastern horizon before dawn on Oct. 26th.
A very thin waning crescent Moon near(ish) Mars above the eastern horizon before dawn on Oct. 26th. Credit: Stellarium / Bob TrembleyVenus and Mercury appear very close to each other in the southwestern sky at dusk on Oct. 22nd – if you use binoculars, and get Venus in your right field-of-view, Mercury will be in your left. Observing this may be a challenge if you have anything obscuring your view of the horizon.
Venus and Mercury appear very near each other before sunset on Oct. 22nd. Credit: Stellarium / Bob TrembleyThe constellations Cygnus and Lyra are directly overhead after sunset this week.
Constellation lines for Cygnus and Lyra. Credit: Stellarium / Bob TrembleyCygnus (the swan) is occasionally referred to as the “northern cross,” and Lyra (the lyre) is host to M57 – the Ring Nebula, this weeks observing target.
Western artwork for the constellations Cygnus and Lyra. Credit: Stellarium / Bob Trembley
M57 – The Ring Nebula
The Ring Nebula (also catalogued as Messier 57, M57 or NGC 6720) is a planetary nebula in the northern constellation of Lyra. Such objects are formed when a shell of ionized gas is expelled into the surrounding interstellar medium by a star at in the last stages of its evolution before becoming a white dwarf.
M57 is an example of the class of planetary nebulae known as bipolar nebulae, whose thick equatorial rings visibly extend the structure through its main axis of symmetry. It appears to be a prolate spheroid with strong concentrations of material along its equator. From Earth, the symmetrical axis is viewed at about 30°. Overall, the observed nebulosity has been currently estimated to be expanding for approximately 1,610 ± 240 years.- Wikipedia
M57, The Ring Nebula in Lyra. Image Credit: NASA/Hubble HeritageHere’s the location of the Ring Nebula in Lyra – I’ve found it fairly easily with my 8″ Dobsonian telescope by just scanning around the middle area between the two stars in Lyra.
Constellation Lyra with the location of M57 highlighted. Credit: Stellarium / Bob TrembleyHere’s the Ring Nebula seen in multiple frequencies:
In this composite image, visible-light observations by NASA’s Hubble Space Telescope are combined with infrared data from the ground-based Large Binocular Telescope in Arizona to assemble a dramatic view of the well-known Ring Nebula. Credit: NASA, ESA, C.R. O’Dell (Vanderbilt University), and D. Thompson (Large Binocular Telescope Observatory)
The Moon is a waning crescent, visible low to the east before sunrise.
The new Moon occurs on Oct. 28th.
The Moon from Oct. 22-28, 2019. Visualizations by Ernie Wright / NASA’s Scientific Visualization Studio.
The sun has not had a spot for 19 days; the northern coronal hole remains huge, the southern hole has diminished and appears almost closed. There is a large and almost cross-shaped coronal hole in the middle of the Sun’s face.
Sun in 193 angstroms (extreme ultraviolet) Oct. 22, 2019. Image courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.Again there have been some impressive prominences on the Sun’s limb over the last couple days.
https://www.facebook.com/photo.php?fbid=10220117290783425&set=gm.2729176887093638&type=3&theater&ifg=1
The solar wind speed is 357.4 km/sec (↓), with a density of 3.1 protons/cm3 (↑) at 1539 UT.
Animated LASCO C2 Coronograph showing the solar corona above the Sun’s limb (the white circle). Credit: NASA/JPL-CaltechYou 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.
Sun News
Upcoming Earth-asteroid encounters:
| Asteroid |
Date(UT)
|
Miss Distance
|
Velocity (km/s)
|
Diameter (m)
|
| 2019 UG1 |
2019-Oct-22
|
5.7 LD
|
8.9
|
20
|
| 2019 UT |
2019-Oct-22
|
2.4 LD
|
11.2
|
9
|
| 2019 UF1 |
2019-Oct-22
|
6.5 LD
|
16.8
|
25
|
| 2019 UJ1 |
2019-Oct-23
|
4.5 LD
|
12
|
11
|
| 2019 UZ |
2019-Oct-23
|
5.7 LD
|
9.6
|
9
|
| 2019 UH |
2019-Oct-24
|
5 LD
|
13.2
|
25
|
| 2019 UD |
2019-Oct-24
|
8.6 LD
|
3.1
|
15
|
| 2019 UA2 |
2019-Oct-25
|
9.3 LD
|
8.7
|
16
|
| 2019 TQ2 |
2019-Oct-25
|
12.8 LD
|
12.4
|
35
|
| 2019 UQ |
2019-Oct-25
|
4.3 LD
|
13
|
21
|
| 162082 |
2019-Oct-25
|
16.2 LD
|
11.2
|
589
|
| 2017 TG5 |
2019-Oct-25
|
14.4 LD
|
11.9
|
34
|
| 2019 UC2 |
2019-Oct-27
|
16.6 LD
|
6.6
|
15
|
| 2019 UT1 |
2019-Oct-28
|
4.7 LD
|
8.8
|
11
|
| 2019 UE1 |
2019-Oct-28
|
8.6 LD
|
6.8
|
24
|
| 2019 UC |
2019-Oct-29
|
2.9 LD
|
8.9
|
53
|
| 2019 TR2 |
2019-Oct-29
|
19.4 LD
|
13.8
|
75
|
| 2019 UB2 |
2019-Oct-29
|
15.1 LD
|
8.4
|
23
|
| 2015 JD1 |
2019-Nov-03
|
12.9 LD
|
11.9
|
269
|
| 2010 JG |
2019-Nov-12
|
19.6 LD
|
14.9
|
235
|
| 2019 UH1 |
2019-Nov-13
|
9.5 LD
|
9.1
|
47
|
| 481394 |
2019-Nov-21
|
11.3 LD
|
7.9
|
372
|
| 2008 EA9 |
2019-Nov-23
|
10.5 LD
|
2.2
|
10
|
| 2017 AP4 |
2019-Dec-03
|
8.5 LD
|
7.5
|
15
|
| 2018 XW2 |
2019-Dec-07
|
17.4 LD
|
13
|
28
|
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
Potentially hazardous asteroids: 2018 (last updated Oct. 1, 2019)
Minor Planets discovered: 829,442 (+108)
Asteroid News
On Oct. 21, 2019, the NASA All Sky Fireball Network reported 44 fireballs.
(21 sporadics, 19 Orionids, 2 epsilon Geminids, 1 southern Taurid, 1 Leonis Minorid)
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.comFireball News – Orinid Meteor Shower Peaks Tonight
Comet C/2019 Q4
Position of the planets and a couple spacecraft in the inner solar system:
Position of the planets and some spacecraft in the inner solar system, Oct. 22 2019 – the orbit of asteroid 101955 Bennu is highlighted. Credit: NASA Eyes on the Solar System / Bob Trembley.Position of the planets and a couple bodies in the middle solar system:
Position of the planets in the middle solar system, Oct. 22, 2019. Credit: NASA Eyes on the Solar System / Bob TrembleyPosition of the planets and a several bodies in the outer solar system:
Position of the planets in the outer solar system, Oct. 22, 2019. Credit: NASA Eyes on the Solar System / Bob TrembleyOrbit of asteroid (and possible dwarf planet) 28978 Ixion:
Orbit of 28978 Ixion (red). Credit: SpaceEngine / Bob Trembley28978 Ixion (/ɪkˈsaɪ.ən/ ik-SY-ən), provisional designation 2001 KX76, is a plutino (an object that has a 2:3 orbital resonance with Neptune). Brown and Tancredi calculate that it is very likely to be a dwarf planet, although the
