On June 23, 2020, I caught this partial crescent just before moonset. Clouds and trees often add interest to a scene. (Bob King)

Astro Bob Nov 16th 2020 - 1pm

Astro Bob: Make a pretty picture of the moon this week

The crescent moon returns at dusk with an inviting smile.

Ferris Hall captured this Leonid fireball several years ago as it streaked toward the constellation Oriion (lower right). (FerrisHall.com/stars)

Astro Bob Nov 15th 2020 - 4pm

Astro Bob: Leonid meteor shower peaks Tuesday morning

Mercury is easy to see now through the next week low in the southeastern sky below Venus from about 90 minutes to one hour before sunrise. (Bob King)

Astro Bob Nov 12th 2020 - 10am

Astro Bob: Shy Mercury joins Venus and the moon at dawn

NASA's Deep Space Climate Observatory (DSCOVR) took this photo of Earth on Nov. 3, 2020. The United States, Mexico and part of Central America is at top with South America to the right of center. (NASA)

Astro Bob Nov 10th 2020 - 12pm

Astro Bob: How to prove the Earth is round

The smoky, gray band low in the eastern sky is the Earth's shadow. It's topped by the pink-hued Belt of Venus. Both rose in the eastern sky shortly after sunset on Nov. 4. (Bob King)

Astro Bob Nov 8th 2020 - 12pm

Astro Bob: Astronomy in the neighborhood — shadows, halos and sunspots

This artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the solar system. The double star Alpha Centauri also appears in the image to the upper-right of Proxima itself. (ESO / M. Kornmesser)

Astro Bob Nov 5th 2020 - 12pm

Astro Bob: What would the sun look like from Alpha Centauri?

Use this map to get oriented. Flora is located in the head of Cetus about a binocular field of view to the right (west) of the star Menkar. (Stellarium)

Astro Bob Nov 3rd 2020 - 4pm

Astro Bob: Flora Blooms in November

The Big Dipper reaches its lowest elevation above the northern horizon — called nadir — in early November around 8-9 p.m. The pale green and pink stripes in the photo are airglow, caused by air molecules that absorb the sun's ultraviolet (UV) light during the day and re-emit it in hues of green, red and blue at night. Airglow happens all around the Earth all the time and causes the night sky to never be completely dark. (Bob King)

Astro Bob Nov 1st 2020 - 3pm

Astro Bob: Tell Time with the Big Dipper

A team of astronomers discovers water in one of the moon's most famous craters. (John Chumack)

Astro Bob Oct 27th 2020 - 2pm

Astro Bob: NASA's flying SOFIA Observatory discovers water inside a sunlit moon crater

Soil and pebbles gathered from the asteroid Bennu leak from a partially-open container in OSIRIS-REx's sample head. NASA scientists are working to store and seal the material to prevent more from escaping. (NASA / Goddard Space Flight Center)

Astro Bob Oct 26th 2020 - 2pm

Astro Bob: Asteroid Probe's Cup Runneth Over

The Apennine Mountains will stand out boldly tonight (Oct. 25) on the 9-day-old moon. All you need to see them is a pair of binoculars and a partly cloudy sky. The mountain range defines the southeastern "shore" of Mare Imbrium, the Sea of Showers. You'll also notice the prominent craters Copernicus (58 miles diameter) and Plato (68 miles). (Bob King)

Astro Bob Oct 25th 2020 - 1pm

Astro Bob: Go Climb a Mountain ... on the Moon!

Uranus is the third largest planet after Jupiter and Saturn. Its atmosphere is mostly hydrogen and helium, but a small amount of methane present tints the globe a pretty shade of aqua. (NASA images)

Astro Bob Oct 20th 2020 - 8pm

Astro Bob: Trick or treat! Uranus at opposition on Halloween

This false-color, composite shows the Orionid meteor shower over Huntsville, Alabama in Oct. 2009. They peak again on the morning of Oct. 21. NASA

Astro Bob Oct 20th 2020 - 9am

Astro Bob: Sparks fly from Orion on Oct. 21-22; watch NASA probe sample an asteroid Oct. 20

In this photo the zodiacal light is the tall, diffuse shaft of light that angles up from beneath the constellation Leo. Bright Venus glares near its base, and the Beehive star cluster appears father up its narrow end. I made the picture on Oct. 16 two hours before sunrise (5:30 a.m.) from Duluth, Minn. facing east over Lake Superior. (Bob King for the News Tribune)

Astro Bob Oct 18th 2020 - 1pm

Astro Bob: October mornings with the zodiacal light / Starlink satellite news

A thin layer of cells at the base of each leaf stem literally cuts the leaf off from the tree. Gravity assists in the process. (Bob King for the Duluth News Tribune)

Astro Bob Oct 14th 2020 - 1pm

Astro Bob: From falling leaves to black holes, gravity works in wondrous ways

Stars in the northern sky describe circular arcs around the North Star in this 45-minute time exposure. Stars closer to Polaris than your latitude circle it without setting and are called circumpolar. Bob King

Astro Bob Oct 13th 2020 - 12am

ASTRO BOB: Oct. 13 dawn celestial trio / Why do some stars never set?

Mars can help us find the variable star Mira in the constellation Cetus the sea monster. The two are currently just a fist and a half apart. Mira is a pulsating variable star that physically expands and contracts, brightening and fading over a period of 332 days. (Bob King)

Astro Bob Oct 11th 2020 - 7pm

ASTRO BOB: Mars meets monstrous, mutable Mira

A poplar tree in full fall regalia frames the waning gibbous moon the morning of Oct. 7, 2020. (Bob King / For the News Tribune)

Astro Bob Oct 7th 2020 - 2pm

ASTRO BOB: Why does the moon shine in the daytime?

Mars leaves a bright glitter path on Lake Superior near Duluth, Minn. on a recent night. (Bob King for the Duluth News Tribune)

Astro Bob Oct 6th 2020 - 10am

Astro Bob: Behold Mars! Red planet closest and brightest until 2035

You can't miss the twinkly, red-orange gleam of Arcturus at dusk in the western sky. Physically and culturally it's one of the most interesting stars in the sky. (DSS2 / Aladin Sky Atlas)

Astro Bob Oct 5th 2020 - 1pm

Astro Bob: Making a cosmic connection with Arcturus

Only the spacecraft's collector head at the end of its robotic arm will touch the asteroid's surface during sample gathering. NASA

Astro Bob Oct 1st 2020 - 3pm

Astro Bob: Daring asteroid mission to take a bite out of Bennu on Oct. 20

The waning gibbous moon will pass under the planet Mars on the night of Oct. 2-3. Observers in parts of the southern hemisphere will see the moon occult the Red Planet. Stellarium

Astro Bob Sep 29th 2020 - 5pm

Astro Bob: Harvest moon meets Mars in stunning Oct. 2 conjunction

A huge aurora fills the northern sky during a major storm on May 7, 2016. (Bob King for the Duluth News Tribune)

Astro Bob Sep 27th 2020 - 3pm

Astro Bob: Pants on! A promising aurora forecast for Sept. 27-29

Saturn (left) and Jupiter have been a familiar sight in the southern sky this summer and fall. Keep an eye on them. In the weeks ahead Jupiter will close the gap. (Bob King for the Duluth News Tribune)

Astro Bob Sep 23rd 2020 - 3pm

Astro Bob: Watch Jupiter and Saturn slow dance to their squeaky-tight 'Great Conjunction'

A sugar maple leaf transitions from summer to fall earlier this week. (Bob King for the Duluth News Tribune)

Astro Bob Sep 22nd 2020 - 3pm

Astro Bob: Summer scurries before fall

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