In the Sky this Week – June 29, 2021

Jupiter and Saturn continue to appear in the southern morning sky all week; the Waning Gibbous Moon appears near Jupiter on June 30th.

Mercury returns to the in the eastern predawn sky at the end of June; it appears highest above the horizon on July 8th, and will vanish into the glare of the Sun around July 20th.

Venus and Mars appear in the western sky at dusk; the two planets continue to appear closer with each passing day, moving towards an exciting close conjunction on July 12th.

There will be a conjunction of Venus and the Beehive star cluster in the west-northwestern sky after sunset on July 2nd.

• The Moon is a Waning Gibbous – rising after sunset, visible high in the sky after midnight, and visible to the southwest after sunrise.
• The Third Quarter Moon occurs on July 1st – rising around midnight, and visible to the south after sunrise.
• After July 1st, the Moon will be a Waning Crescent – visible low to the east before sunrise.

If you click on the Moon image above, or click this link, you will go to NASA’s Moon Phase and Libration, 2021 page – it will show you what the Moon looks like right now. If you click the image on that page, you will download a high-rez TIFF image annotated with the names of prominent features – helpful for logging your lunar observations!

Moon News:

The Sun has 3, count them 3 spots! Hah ha ha ha! *AHEM* Excuse me… my granddaughter has been watching Sesame Street when she’s been over here visiting.

The two nearby spots are blowing off C-class solar flares; SpaceWeather.com says: “NOAA analysts have modeled a CME that left the sun on June 27th. Their conclusion: “[It will] likely miss Earth. However, due to a moderate level of uncertainty, there is a possibility of weak influences from the flanking edge of the CME on July 1st.”

Solar Activity on Facebook – Run by Volunteer NASA/JPL Solar System Ambassador Pamela Shivak

Solar Corona

Solar wind speed is 337.6 km/sec ▼, with a density of 6.7 protons/cm³ ▼ at 1251 UT.

Click here to see a near real-time animation of the corona and solar wind from the Solar & Heliospheric Observatory (SOHO).

Sun News:

• Near-Earth Objects (NEOs) discovered this month: 155, this year: 1287 (+9), all time: 26,123 (+11)
• Potentially hazardous asteroids: 2188 (+3) (updated 2021-06-29)
• Total Minor Planets discovered (NASA): 1,097,148 (+1,923)
• Total Minor Planets discovered (MPC): 1,086,655 (updated 2021-06-22)

Recent & Upcoming Earth-asteroid encounters:

Asteroid News:

On June 28, 2021, the NASA All Sky Fireball Network reported 5 fireballs!
(5 sporadics)

Fireball News:

If you see a bright meteor or a fireball, please REPORT IT to the American Meteor Society and the International Meteor Organization!

Position of the planets & several spacecraft in the inner solar system on June 29th – the orbit of comet 67P is highlighted:

Position of the planets in the middle solar system – the orbit of asteroid 4 Vesta is highlighted:

Position of the planets in the outer solar system – the orbit of comet C/2014 UN₂₇₁ is shown in red:

This comet has caused something of a stir in the astronomical community – it’s an Oort-cloud object, and it’s BIG: 100-200 km in size! Its closest approach to the Sun will be between the orbits of Saturn and Uranus in 2031; it will take ~4.5 million years to reach it aphelion.

I used SpaceEngine to visualize the comet’s orbit; I wanted to see the other end of its orbit, so I zoomed-out… and kept zooming, and kept zooming until nearby stars started to visibly move! One of those stars was Alpha Centauri – so I clicked on it, and looked back at the Sun. The orbit of comet C/2014 UN₂₇₁ was HUGE in Alpha Centauri’s sky!

Solar System News:

See a list of current NASA missions here: https://www.jpl.nasa.gov/missions?mission_status=current

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.

Exoplanet News:

Adrian Bradley is a buddy, and president of the Great Lakes Association of Astronomy Clubs.

SpaceWeather.com Realtime Aurora Gallery: https://spaceweathergallery.com/aurora_gallery.html

June is now Colorado’s Dark Sky Month!

• Visit an International Dark Sky Park: https://www.darksky.org/our-work/conservation/idsp/parks/
• If you live in Michigan, visit the Michigan Dark Skies site: https://sites.lsa.umich.edu/darkskies/

Hubble Space Telescope – Helping see the Beauty of the Cosmos

Located in the constellation Hydra, this colorful, swirling spiral galaxy is known as M83. A “starburst” galaxy, M83 is considerably smaller than our own galaxy but is producing stars at a much faster rate. The pink clouds of hydrogen gas that dot the galaxy’s spiral arms are the nurseries where new stars are being born. The blue, grainy clumps mixed in with these star-forming regions are clusters of hot, young stars that have blown away the surrounding gas with their fierce ultraviolet radiation. Some of these young stars are only about a million years old. The yellow glow closer to the center of the galaxy comes from more mature stars that have lived for 100 million years or more.

Astronomers are using Hubble’s detailed examinations of M83 to investigate how stars form in clusters, how those clusters disperse over time, and how the stars eventually die, redistributing their contents into space for future generations of stars to build upon.

For example, astronomers — including Rupali Chandar of the University of Toledo, Brad Whitmore from the Space Telescope Science Institute, and their collaborators — have been scrutinizing Hubble’s high-resolution images in order to estimate the ages of star clusters in M83. This information reveals how many star clusters survive to old age and how many disband while their stars are still young. These studies suggest that star clusters form the same way throughout the galaxy. However, several research teams have found that more clusters are destroyed in the inner regions of M83 than the outer regions, indicating that environment may influence how long a cluster sticks together.

Volunteers inspected Hubble images of M83 to classify the cluster’s ages based on physical characteristics, providing more accurate age estimates than those generated by an automatic computer algorithm.

A citizen-science project entitled Star Date: M83 also enlisted the aid of the general public in analyzing the ages of the galaxy’s star clusters. Volunteers inspected Hubble images of M83 to classify the cluster’s ages based on physical characteristics, providing more accurate age estimates than those generated by an automatic computer algorithm.

As a consequence of producing lots of new stars, M83 is also rife with stellar death. In the past century, observers have witnessed six stellar explosions, called supernovae, in M83 — more than in almost any other known galaxy. Hubble has helped identify the remnants of these supernovae and hundreds of others in M83, including one from what appears to be a recent supernova not observed by anyone on Earth. Analyzing Hubble’s observations, a team led by William Blair of the Johns Hopkins University has found evidence that environment also affects how these catastrophic stellar deaths disperse the raw materials for new star formation into the galaxy. – NASA