This image shows the PDS 70 planetary system, located nearly 400 light-years away and still in the process of being formed. The central star (center) has at least two planets orbiting it: PDS 70b (not visible in the image) and PDS 70c, the dot to the right of the star. The planets have carved out a cavity in the orange, ring-like disk of material as they gobble up the dust there. During this process, PDS 70c acquired its own circumplanetary disk, where young moons may lurk. (ALMA (ESO/NAOJ/NRAO)/Benisty et al.)

Astro Bob 2:37 pm, Jul. 25, 2021

Astro Bob: Astronomers spot moon-forming disk around Jupiter-like exoplanet

There are more moons than planets in our solar system. Yet convincing evidence of moons among the nearly 5,000 known extrasolar planets has been scant … until now.

A couple enjoys each other's company on Brighton Beach at Lake Superior in Duluth during the last month's full moon. (Bob King)

Astro Bob 3:45 pm, Jul. 22, 2021

Astro Bob: Full Moon may look unusually red this week

This map shows the sky facing east on July 15, 3000 BC from the ancient city of Memphis (near Cairo) in Egypt. Sirius stands 3° high 32 minutes before sunrise around the time of its heliacal rising on that date. Venus joins the scene deeper in the solar glare. (Stellarium)

Astro Bob 4:07 pm, Jul. 20, 2021

Astro Bob: Dog Days bring summer swelter — blame Sirius

Delphinus the Dolphin is a small but easy-to-find constellation near the bottom of the bright Summer Triangle asterism. (Bob King)

Astro Bob 10:42 am, Jul. 19, 2021

Astro Bob: Delphinus, cutest constellation, has a tale or two to tell

This is the third of five space station orbits over northern Minnesota on the night of July 13-14. During this pass, which started at 1:18 a.m., the ISS cuts across through the Big Dipper (left). A firefly (right) makes a "pass" of its own at the same time. (Bob King)

Astro Bob 2:43 pm, Jul. 14, 2021

Astro Bob: Night vigil with the space station

Jupiter dominates the southeastern sky when it rises above the tree line around 11:30 p.m. in mid-July. This photo was taken around midnight July 8, 2021. (Bob King)

Astro Bob 10:54 am, Jul. 13, 2021

Astro Bob: What's that bright star in the east at midnight?

The moon seems to float above the fuzzy blue edge of Earth's atmosphere as seen from the International Space Station. (Reid Wiseman / NASA)

Astro Bob 5:09 pm, Jul. 11, 2021

Astro Bob: Where does outer space begin?

Mars and Venus were 3.2° apart on July 7th seen from Rice Lake, Minnesota, an hour after sundown (10:05 p.m.) What looks like clouds is smoke from Canadian wildfires. (Bob King)

Astro Bob 3:20 pm, Jul. 8, 2021

Astro Bob: Venus and Mars 'kiss' in close conjunction before parting

Looking like a nighttime metropolis from orbit, the globular cluster M13 glitters with an estimated 300,000 stars. It's located 25,000 light-years from the Earth and spans 145 light-years — more than the distance from Earth to the stars of the Big Dipper. {NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

Astro Bob 4:06 pm, Jul. 7, 2021

Astro Bob: Night Fever under the great disco ball of Hercules

A tiger swallowtail butterfly gathers nectar from an orange hawkweed flower this past June. Butterflies, like many creatures, return when Earth's axis tilts sunward during the summer. (Bob King)

Astro Bob 4:24 pm, Jul. 4, 2021

Astro Bob: Happy aphelion! You've finally arrived on the far side

Towering cumulus clouds cast dramatic beams of sun and shadow called crepuscular rays on June 28, 2021. (Bob King)

Astro Bob 4:08 pm, Jul. 1, 2021

Astro Bob: What makes sunbeams and moonbeams?

Cepheus, a mythical king of Ethiopia, has a place in the northern sky alongside his wife, Queen Cassiopeia. Both constellations are circumpolar from mid-northern latitudes, meaning they circle around the North Star and never set. (Urania's Mirror / Sidney Hall)

Astro Bob 8:32 pm, Jun. 29, 2021

Astro Bob: Meet Cassiopeia's husband Cepheus

Draco the Dragon, the eight largest constellation, winds between the two Dippers in the northern sky. The head of the dragon is a small rhombus called the Lozenge, located not far from the bright star Vega in Lyra the Lyre. (Stellarium)

Astro Bob 3:08 pm, Jun. 27, 2021

Astro Bob: Draco awaits — let's go dragon hunting!

That slightly fuzzy star at center is C/2014 UN271, an exceptionally large comet approaching from the remote comet repository called the Oort Cloud in the outer solar system. The photo was taken on June 22, 2021. (SkyGems Remote Observatory in Namibia by Luca Buzzi, Andrea Aletti and Lukas Demetz)

Astro Bob 3:26 pm, Jun. 24, 2021

Astro Bob: Astronomers discover giant comet from deep space, plus see Strawberry Moon

A spectacular display of noctilucent cloud mingles with darker cirrus clouds over Rice Lake, Minn., around 10:15 p.m. June 19. Right now, it's high season for these unique, high clouds that form on meteor soot. (Bob King)

Astro Bob 11:28 am, Jun. 22, 2021

Astro Bob: Mars enters a beehive, bright noctilucent clouds and the moon shines near Antares

People surround the floodlit stones of Stonehenge in England the night before the summer solstice on June 21, 2005. On the solstice, the sun rises over the Heel Stone outside the entrance to the monument and illuminates its center. You can watch the sunset show live from 10:07 to 11:37 p.m. CDT on June 20 at https://bit.ly/3wJdHrk (Andrew Dunn / CC BY-SA 2.0)

Astro Bob 4:16 pm, Jun. 20, 2021

Astro Bob: Shortest night, longest day — summer solstice arrives Sunday night

Fireflies glide, dip and rise in a field along a forest edge in Lakewood Township, Minn., around midnight June 17, 2021. Details: ISO 400, 150mm lens at f/3.2, 150-second exposure. (Bob King)

Astro Bob 1:50 pm, Jun. 18, 2021

Astro Bob: Fireflies flash, stars twinkle, we connect

A camera placed on the Martian surface by the Chinese rover (left) took this group selfie of the rover and its landing platform. (CNSA)

Astro Bob 2:00 pm, Jun. 16, 2021

Astro Bob: Down in front on China's Mars

A spectacular coronal mass ejection (CME) on Feb. 27, 2000 blasts a billion tons of heated, ionized gas called plasma into space. Plasma is a mix of electrons and protons, two of the key particles that make up atoms. An opaque disk blocks the sun from view. The circle marks the sun's position. NASA / ESA / SOHO white circle indicates the sun’s surface.

Astro Bob 12:06 pm, Jun. 14, 2021

Astro Bob: Surfing electrons electrify northern lights

The moon appeared directly in front of the sun during Thursday's solar eclipse. Friday, June 11, it returns to the western evening sky, looking pretty not far from Venus about 45 minutes after sunset. (Stellarium)

Astro Bob 1:40 pm, Jun. 11, 2021

Astro Bob: The moon throws out more candy

This is how the sun first appeared when it cleared the clouds over Canada Thursday, June 10 shortly after sunrise. (Bob King)

Astro Bob 9:39 pm, Jun. 10, 2021

Astro Bob: Cosmic communion at 39,000 feet

The full band of the summer Milky Way tilts upward from the southern horizon around midnight in early June. The Milky Way is also the name of our galaxy, home to the sun and all the nighttime stars. (Bob King)

Astro Bob 2:01 pm, Jun. 6, 2021

Astro Bob: Silent as stone, the Milky Way sets the night aglow

A "ring of fire" surrounds the moon during the May 20, 2012, annular solar eclipse. The name comes from the Latin annulus for "little ring." During an annular eclipse the moon passes directly over the sun but doesn't completely cover it because it's farther away and appears smaller than normal. (Kevin Baird / https://bit.ly/2SUJeay)

Astro Bob 12:44 pm, Jun. 4, 2021

Astro Bob: Ring of Fire eclipse blazes at sunrise June 10

Feathery, blue noctilucent clouds streak the northwestern sky in deep dusk from the shore of Lake Superior near Ironwood, Mich. last July. (Bob King)

Astro Bob 8:12 am, Jun. 2, 2021

Astro Bob: Noctilucent clouds return as the summer solstice approaches

This illustration depicts NASA’s Europa Clipper spacecraft which is expected to launch in 2024. The probe will investigate whether Jupiter’s moon Europa and its internal ocean have conditions suitable for life (NASA/JPL-Caltech)

Astro Bob 3:10 pm, May 30, 2021

Astro Bob: Jupiter's moon Europa may rumble with seafloor volcanoes

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