In the Sky This Week – April 7, 2020
Last night, I gave the featured presentation during the Warren Astronomical Society's online WebEx/YouTube meeting: The Challenges of Interstellar Travel. I cannot believe how much I learned putting this presentation together; honestly, there's probably weeks more research I could do, and papers I could read.
I discussed sending small probes and giant generation ships to the stars, and the enormous amount of energy, resources and manufacturing it would require. I talked about physical and mental problems related to space travel, and what it would take to keep humans alive during an interstellar voyage. I concluded my presentation suggesting maybe we should make sure all the life-support systems are functioning properly on the generation ship we all share, and are travelling through interstellar space aboard.
The NASA at Home page has links to lots of online NASA resources for things to do at home - here's a couple:
- Space Place parents and educators page: https://spaceplace.nasa.gov/menu/parents-and-educators/
- Solar System Exploration's 10+ things: https://solarsystem.nasa.gov/news/1192/10-things-to-do-with-nasa-at-home/
- NASA Office of STEM Engagement: https://www.nasa.gov/stem-at-home-for-students-k-4.html
You'll see some redundancy; NASA is trying to put the lists out there on different sites where folks might typically go.
The three-planet conjunction of Mars, Jupiter and Saturn in the early morning southeastern sky continues with Mars pulling away from Saturn each morning.

Conjunction of Saturn, Mars and Jupiter in the southeastern predawn sky on April 7th. Credit: Stellarium / Bob Trembley.
The Moon joins the three-planet conjunction on the mornings of April 13-17.

Conjunction of Saturn, Mars, Jupiter and the Moon in the southeastern predawn sky on April 13th. Credit: Stellarium / Bob Trembley.
Venus passed through the Pleiades star cluster on April 6th, and now appears "above" the Pleiades in the western sky at dusk.

Venus now appears above the Pleiades star cluster, and the star Aldebaran is a short way away in the western sky after sunset this week. Credit: Stellarium / Bob Trembley.
Several members of the Warren Astronomical Society showed images they took of the conjunction of Venus and the Pleiades during our online meeting; Doug Bock, an avid astrophotographer, was able to share his screen and flip through several images he'd processed - that was very cool! Doug tweeted several of those images:
Venus and the Pleiades on April 3, 2020 pic.twitter.com/U3XCJilxe3
— Doug Bock (@Mars_1956) April 4, 2020
Comet C/2019 Y4 (Atlas) on April 3, 2020
33 x 60 second frames stacked on the core of the comet.
10" f/8 RC, ZWO asi071mc PRO camera @ gain 400 pic.twitter.com/K73ROVzWE0— Doug Bock (@Mars_1956) April 5, 2020
M 101 from March 22, 2020 pic.twitter.com/m8cDwyjF1X
— Doug Bock (@Mars_1956) March 22, 2020
The Moon is a waxing gibbous - visible to the southeast in early evening, and up for most of the night.
The full Moon occurs on April 8th - it rises at sunset, is visible high in the sky around midnight, and is visible all night.
After April 8th, the Moon will be a waning gibbous - rising after sunset, visible high in the sky after midnight, and visible to the southwest after sunrise.

The Moon from 2020-04-07 - 2020-04-13. Visualizations by Ernie Wright / NASA's Scientific Visualization Studio.
Moon News
I saw this and said "I didn't know that! I've got to include it!"
"Well, at least something worked on this flight."
- Jim Lovell, Apollo 13During Apollo 13's journey, the crew sent a rocket booster to intentionally impact the Moon. A seismometer set up during Apollo 12 recorded the activity. https://t.co/dFXSdu2fkp
— NASA Moon (@NASAMoon) April 6, 2020
The end of the video states:
"The [lunar] seismograph network recorded more than 13,000 seismic events and delivered some of the most important scientific results of the Apollo missions."
I really wish we had a functioning network of lunar seismometers!
The Sun has been spot-free for 2 days, however the remnants sunspot AR2759 can be seen in the videos below as bright patches above the equator. The northern coronal hole has reopened; the southern coronal hole continues to be open and huge.
The Sun seen in 193 angstroms (extreme ultraviolet) Apr. 6, 2020:
Several looping prominences on the Sun's limb over the last couple days.
The Sun seen in 304 angstroms (extreme ultraviolet) Apr. 6, 2020:
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.
Facebook: SolarActivity
Take a close look at that loop - just WOW! Every time I see gorgeous amateur photography of the Sun like this, I can't help but think how much the solar astronomers of the mid-late 1800's would have LOVED to see these.
Solar Corona
Solar wind speed is 305.5 km/sec (↓↓), with a density of 2.0 protons/cm3 (↓↓) at 1136 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
Take a breath. Relax. If you've got a half-hour, you can "sunbathe" with @NASASun's SDO, via this 30-minute 4K montage, set to appropriately atmospheric music. Sunglasses optional, but headphones are a must! 😎🎧 https://t.co/tgrff0DRrN #NASAatHome #MusicMonday pic.twitter.com/UvXRq9GPpV
— NASA Goddard (@NASAGoddard) April 6, 2020
Potentially hazardous asteroids: 2018 (last updated Oct. 1, 2019)
Total Minor Planets discovered: 957,783 (+187)
Upcoming Earth-asteroid encounters:
Asteroid |
Date(UT)
|
Miss Distance
|
Velocity (km/s)
|
Diameter (m)
|
2020 GE1 |
2020-Apr-06
|
3.7 LD
|
4.6
|
14
|
2020 FQ6 |
2020-Apr-06
|
17.9 LD
|
11.2
|
37
|
2020 GN1 |
2020-Apr-06
|
7.7 LD
|
6.5
|
13
|
2020 GB1 |
2020-Apr-06
|
1.1 LD
|
8.3
|
15
|
2020 GQ1 |
2020-Apr-07
|
4.4 LD
|
16.9
|
16
|
2020 GW1 |
2020-Apr-08
|
5.9 LD
|
13.2
|
23
|
2020 GF1 |
2020-Apr-08
|
1.5 LD
|
6.1
|
21
|
2020 FL4 |
2020-Apr-09
|
10.4 LD
|
4.6
|
15
|
2015 GK |
2020-Apr-09
|
12.2 LD
|
12.9
|
25
|
2020 FW4 |
2020-Apr-09
|
19.7 LD
|
18.6
|
161
|
2020 GE |
2020-Apr-10
|
5.4 LD
|
2.2
|
8
|
2019 HM |
2020-Apr-10
|
7.2 LD
|
3.2
|
23
|
2020 GM1 |
2020-Apr-11
|
10.2 LD
|
25.6
|
67
|
2020 GU1 |
2020-Apr-11
|
5.9 LD
|
6.9
|
10
|
2020 GG |
2020-Apr-11
|
9.7 LD
|
5.5
|
17
|
363599 |
2020-Apr-11
|
19.2 LD
|
24.5
|
224
|
2020 FX3 |
2020-Apr-15
|
14.1 LD
|
10.3
|
56
|
2020 FZ6 |
2020-Apr-15
|
20 LD
|
21.7
|
189
|
2020 FV6 |
2020-Apr-19
|
10.8 LD
|
19.7
|
88
|
2019 HS2 |
2020-Apr-26
|
13.6 LD
|
12.6
|
17
|
2019 GF1 |
2020-Apr-27
|
18.7 LD
|
3.2
|
12
|
2020 FM6 |
2020-Apr-27
|
14.3 LD
|
16.9
|
156
|
52768 |
2020-Apr-29
|
16.4 LD
|
8.7
|
2457
|
2020 DM4 |
2020-May-01
|
18.4 LD
|
6.4
|
162
|
438908 |
2020-May-07
|
8.9 LD
|
12.8
|
282
|
2016 HP6 |
2020-May-07
|
4.3 LD
|
5.7
|
31
|
388945 |
2020-May-10
|
7.3 LD
|
8.8
|
295
|
2000 KA |
2020-May-12
|
8.9 LD
|
13.5
|
162
|
478784 |
2020-May-15
|
8.5 LD
|
3.6
|
28
|
136795 |
2020-May-21
|
16.1 LD
|
11.7
|
892
|
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
On Apr. 6, 2020, the NASA All Sky Fireball Network reported 4 fireballs.
(4 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 & Meteor News:
Very bright #fireball detected by our camera @Museum_Cardiff in the early hours of this morning! @UKMeteorNetwork @FireballsUK #Fripon #shootingstars #spacerocks pic.twitter.com/lDEGCJjfQF
— SCAMP (@SCAMP_Meteors) April 7, 2020
Position of the planets and a couple spacecraft in the inner solar system.

Position of the planets and a couple spacecraft in the inner solar system, 2020-04-07. Credit: NASA Eyes on the Solar System / Bob Trembley.
Position of the planets in the middle solar system.

Position of the planets in the middle solar system 2020-04-07. Credit: NASA Eyes on the Solar System / Bob Trembley.
Position of the planets some transneptunian objects in the outer solar system - a small part of Sedna's orbit is highlighted.

Position of the planets in the outer solar system 2020-04-07- part of the orbit of transneptunian object Sedna is highlighted. Credit: NASA Eyes on the Solar System / Bob Trembley.
OSIRIS-REx Asteroid Sample Return Mission
Browse the full collection of 321Science videos here: https://t.co/ZuTcrg459o
(PSA: these videos are great for kids! 🖍)
— NASA's OSIRIS-REx (@OSIRISREx) April 2, 2020
Hubble Space Telescope
This galaxy, named NGC 2273, hosts an inner ring and two outer “pseudorings”. Having so many distinct rings is rare, and makes NGC 2273 unusual.
Credit: @ESA / @Hubble_Space / @NASA , J. Greene https://t.co/NMKPQTGhaw pic.twitter.com/jaTigut1Is
— HUBBLE (@HUBBLE_space) April 6, 2020
International Space Station
The @SpaceX #Dragon resupply ship was released at 9:06am ET from the @CSA_ASC #Canadarm2. Dragon will splashdown in the Pacific around 2:50pm loaded with science and gear. pic.twitter.com/AXjTBxJVMc
— Intl. Space Station (@Space_Station) April 7, 2020
Climate
Even with COVID-19, NASA’s many missions and personnel are doing what they do best, but from home offices and via video conferencing. This includes monitoring how our planet might respond to changes in human activity due to quarantines. https://t.co/DpkGbuzyTI
— NASA Climate (@NASAClimate) April 6, 2020
ex·o·plan·et /ˈeksōˌplanət/, noun: a planet orbiting a star other than the Sun.
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.
Let the natural lights shine! Earth Hour is on 24th March, between 8:30pm and 9:30pm. Join millions of people who are taking a stand against climate change by turning off your lights for one hour. The Elan Valley is an IDA Dark Sky Park which is protected from light pollution. pic.twitter.com/L7CaxuhANd
— Elan Valley (@Elan_Valley) March 23, 2018
The Local Stellar Neighborhood
Continuing with my visual tour of nearby stars and their systems, we travel to Lacaille 9352, 10.73 light years distant.

Distance to Lacaille 9352 from Sol; the plane (green) is aligned with the orientation of the plane of the Milky Way galaxy. Credit: SpaceEngine / Bob Trembley.
Lacaille 9352
Lacaille 9352 is a red dwarf star in the southern constellation of Piscis Austrinus. With an apparent visual magnitude of 7.34, this star is too faint to be viewed with the naked eye even under excellent seeing conditions. Parallax measurements place it at a distance of about 10.74 light-years (3.29 parsecs) from Earth. It is the eleventh closest star system to the Solar System and is the closest star in the constellation Piscis Austrinus. The ChView simulation shows that its closest neighbour is the EZ Aquarii triple star system at about 4.1 ly from Lacaille 9352.
This star has the fourth highest known proper motion, (which was first noticed by Benjamin Gould in 1881) moving a total of 6.9 arcseconds per year. However, this is still a very small movement overall, as there are 3,600 arcseconds in a degree of arc. The space velocity components of this star are (U, V, W) = (−93.9, −14.1, −51.4) km/s. If the radial velocity (Vr) equals +9.7 km/s then about 2,700 years ago Lacaille 9352 was at its minimal distance of approximately 10.63 ly (3.26 pc) from the Sun.
The spectrum of Lacaille 9352 places it at a stellar classification of M0.5V, indicating it is a type of main sequence star known as a red dwarf. This was the first red dwarf star to have its angular diameter measured, with the physical diameter being about 46% of the Sun's radius. It has around half the mass of the Sun and the outer envelope has an effective temperature of about 3,626 K.- Wikipedia
As of this writing, Lacaille 9352 has no known exoplanets; when I traveled there in SpaceEngine, there were multiple procedurally generated planets, some large, several with moons. I probably spent way too much time poking around in the system to find good spots to take screen-shots. This star is exactly the type Project EDEN (and the VATT) would be looking at; I'll be discussing Project EDEN in a future post.
- Artist’s concept of a hypothetical exoplanet (left) orbiting the red dwarf star Lacaille 9352 seen from above one of its many moons. SpaceEngine / Bob Trembley
- Artist’s concept of a hypothetical exoplanet orbiting the red dwarf star Lacaille 9352 seen from the surface of one of its moons. SpaceEngine / Bob Trembley
Stay safe, be well, and look up!
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