Updating the Near-Earth Object stats for this post, I noticed that the number of known NEO’s has crossed the 20,000 threshold! I need to update this chart every time I talk about asteroids – note the steep angle of the discovery curve, and how the curve keeps growing… precipitously!

If you get up at the crack of dawn, and look really low towards the eastern horizon, you may catch a glimpse of Mercury near Venus. Both planets will appear a bit lower in the sky each morning this week.

Saturn, Jupiter and the star Antares appear in southern predawn sky all week; it’s interesting to note that for the last several weeks these all appeared in the south-southeastern predawn sky.

Mars and the constellations Orion and Taurus appear in the western sky after sunset. Mars has dimmed significantly since last year; it and the two constellations appear a bit lower in the western sky each evening.

Mars continues a slow crawl away from the Pleiades in the western sky after sunset. Mars appears very near the star Tau Tauri (τ Tau) on April, 18th.

The full Moon appears near the star Spica in the southeastern sky after sunset on April 18th.

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 Apr. 19th, rising at sunset, visible high in the sky around midnight, and visible all night long.
After the 19th, the Moon will be a waning gibbous, rising after sunset, visible high in the sky after midnight, and visible to the southwest after sunrise.

Moon News
As I was writing this post:
AR2738 continues to rotate across the face of the Sun, coronal loops following it; in previous days the region was blowing off multiple B-class solar flares, but now it appears to be quieting down. Astrophographer Marty Wise took this beautiful image of AR2738 showing a “light bridge” crossing the spot!
The northern coronal hole remains closed, and it appears as if the southern hole has greatly diminished.
Light prominence activity around the Sun’s limb; you can see a few things being spewed out of AR2738 over the last couple days..
The solar wind speed is 381.9 km/sec (↓), with a density of 2.1 protons/cm3 (↓).

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.
Sun News
Upcoming Earth-asteroid encounters:
Asteroid |
Date(UT)
|
Miss Distance
|
Velocity (km/s)
|
Diameter (m)
|
2012 XO134 |
2019-Apr-18
|
14.8 LD
|
11
|
56
|
2019 FN2 |
2019-Apr-18
|
4.1 LD
|
7.8
|
68
|
522684 |
2019-Apr-19
|
19 LD
|
11.5
|
214
|
2019 GM |
2019-Apr-21
|
19.4 LD
|
10.4
|
37
|
2019 FV2 |
2019-Apr-22
|
15.6 LD
|
2.3
|
33
|
2019 GF1 |
2019-Apr-27
|
4.7 LD
|
1.9
|
11
|
2018 KK1 |
2019-May-05
|
13.9 LD
|
13.9
|
71
|
2017 RC |
2019-May-09
|
14.5 LD
|
10.6
|
9
|
2008 HS3 |
2019-May-09
|
14.6 LD
|
5.3
|
162
|
2018 VX8 |
2019-May-12
|
6.2 LD
|
15.5
|
118
|
2019 GT1 |
2019-May-17
|
6.1 LD
|
4
|
36
|
2012 KT12 |
2019-May-18
|
3.3 LD
|
3.9
|
20
|
2015 KQ18 |
2019-May-25
|
10.7 LD
|
13.1
|
30
|
66391 |
2019-May-25
|
13.5 LD
|
21.5
|
1780
|
2003 LH |
2019-May-28
|
15.6 LD
|
7.4
|
32
|
2011 HP |
2019-May-30
|
12.3 LD
|
8.4
|
135
|
2014 MF18 |
2019-Jun-06
|
8.8 LD
|
3
|
22
|
Notes: LD means “Lunar Distance.” 1 LD = 384,401 km, the distance between Earth and the Moon. Table from SpaceWeather.com
Potentially hazardous asteroids: 1967 (last updated Feb. 26, 2019)
Minor Planets discovered: 794,460 (+338)
Asteroid News
Keep an eye out for meteors and fireballs during the Lyrid meteor shower this week!
Active from April 16th to April 28th, 2019
The Lyrids are a medium strength shower that usually produces good rates for three nights centered on the maximum. These meteors also usually lack persistent trains but can produce fireballs. These meteors are best seen from the northern hemisphere where the radiant is high in the sky at dawn. Activity from this shower can be seen from the southern hemisphere, but at a lower rate.
Shower details – Radiant: 18:04 +34° – ZHR: 18 – Velocity: 30 miles/sec (medium – 48.4km/sec) – Parent Object: C/1861 G1 (Thatcher)
Next Peak – The Lyrids will next peak on the Apr 21-22, 2019 night. On this night, the moon will be 92% full. – American Meteor Society
On Apr. 15, 2019, the NASA All Sky Fireball Network reported 8 fireballs.
(8 sporadics)

Fireball News
A Comet over Notre Dame, 1858
I saw this illustration posted numerous times on Twitter after part of Notre Dame burned down on April 15, 2019. My wife and I have not visited Paris; my daughter, who visited Paris a couple years ago, is devastated!

This is the position of the planets and a couple bodies in the solar system:
Solar System News
OSIRIS-REx – Observing Asteroid Bennu from Oblique Angles
Juno at Jupiter
JAXA HAYABUSA2 – Performs First Collision Experiment with an Asteroid
From the History Books: Deep Impact’s Impact Experiment on Comet Tempel 1 in 2005

Mars Insight – Investigations into Drill Problem Continue
Climate
Earth Climate Observing Satellites from NASA’s Eyes on the Earth app – you can see info on each satellite, and overlay and animate satellite data on the globe.

TESS numbers are starting to climb!
Data from the NASA Exoplanet Archive
Exoplanet News
Exoplanet Artwork by Bob Trembley

Kepler-16 b – The existence of a world with a double sunset, as portrayed in the film Star Wars more than 30 years ago, is now scientific fact. NASA’s Kepler mission has made the first unambiguous detection of a circumbinary planet – a planet orbiting two stars – 200 light-years from Earth.
Unlike Star Wars’ Tatooine, the planet is cold, gaseous and not thought to harbor life, but its discovery demonstrates the diversity of planets in our galaxy. Previous research has hinted at the existence of circumbinary planets, but clear confirmation proved elusive. Kepler detected such a planet, known as Kepler-16b, by observing transits, where the brightness of a parent star dims from the planet crossing in front of it.
[Read More: NASA’s Kepler Mission Discovers a World Orbiting Two Stars]