In this ultraviolet (UV) photo taken with NASA's Solar Dynamics Observatory, a bright solar flare detonates in sunspot group 2824 around 4:45 p.m. CDT on May 22nd. (NASA / SDO)

Astro Bob 7:03 pm, May 24, 2021

Astro Bob: Solar explosions could spark northern lights May 25-26

A series of solar eruptions is expected to produce a moderate geomagnetic storm starting Tuesday night, May 25 and continuing through Wednesday morning.

I captured several scenes of the partial phases and totality from the last total lunar eclipse on January 20, 2019. The sunlit part of the moon is overexposed to better show the colorful shading of the shadowed part. (Bob King)

Astro Bob 3:52 pm, May 23, 2021

Astro Bob: Wake up for Wednesday's dawn supermoon eclipse

An artist's conception of the Tianwen-1 lander on Mars with the rover on top and ramp extended. (CNSA)

Astro Bob 2:38 pm, May 20, 2021

Astro Bob: Traffic jam on Mars? Zhurong rover sends back first photos

A train of Starlink satellites marches across the W of Cassiopeia on May 8, 2021. As satellite numbers rapidly rise, it may soon become impossible to gaze at a starry sky uninterrupted by artificial "stars." (Bob King)

Astro Bob 12:25 pm, May 18, 2021

Astro Bob: Take a deep breath, thousands more satellites are on the way

During this time exposure made around 10:55 p.m. on May 15, the space station cuts through the band of the Milky Way as it heads toward the eastern horizon. Multiple passes are visible each night for about the next two weeks. (Bob King)

Astro Bob 1:33 pm, May 16, 2021

Astro Bob: Join the marathon and see the space station all night long

The Hubble Space Telescope captured this photo of Jupiter in visible light on Jan. 11, 2017. The Great Red Spot stands out prominently in the lower left, while the smaller feature nicknamed Red Spot Jr. (known to Jovian scientists as Oval BA) appears to its lower right. The two most prominent cloud belts, riddled with snaking cloud forms, are the North and South Equatorial Belts. (NASA/ESA/NOIRLab/NSF/AURA/M.H. Wong and I. de Pater et al. Acknowledgments: M. Zamani)

Astro Bob 9:21 pm, May 13, 2021

Astro Bob: Meet Jupiter, a planet with plenty of atmosphere

Venus and the crescent moon appear 1° apart at dusk on July 15, 2018. They'll be just as close on May 12 at dusk. (Bob King)

Astro Bob 11:39 am, May 11, 2021

Astro Bob: See Venus and the moon in their closest conjunction of the year

A nova that first appeared in Cassiopeia in March has recently become bright enough to easily spot in binoculars. It's located to the right of the "W" and visible all night long from mid-northern latitudes. (Stellarium)

Astro Bob 2:21 pm, May 9, 2021

Astro Bob: See a nova explosion in Cassiopeia

Venus is that little dot shining all by itself above center. Given a clear or partially clear sky, the planet is easy to see during early dusk in May. I took this photo on May 4 about 40 minutes after sunset around 9 p.m. local time. (Bob King)

Astro Bob 1:38 pm, May 5, 2021

Astro Bob: Ah, so good to have Venus back

A bright Eta Aquariid meteor shoots across the northern lights on May 6, 2013. Both the meteor and the aurora lie at approximately the same altitude of 70 miles (113 km). (Bob King)

Astro Bob 1:31 pm, May 3, 2021

Astro Bob: Bits of Halley's Comet to etch the predawn sky May 4-6

In this simulation, an astronaut reaches 9 feet (2.7 meters) from a standing jump on the moon. (Still frame from Engineering and Architecture group on YouTube)

Astro Bob 11:22 am, May 2, 2021

Astro Bob: How high could you jump on other planets?

Several complete and broken chondrules glow in technicolor in this thin slice of meteorite viewed under a 30x microscope. Chondrules are 4.56 billion years old and may represent the first solid material that formed in the solar system. (Bob King)

Astro Bob 1:58 pm, Apr. 28, 2021

Astro Bob: Chondrules — stained glass of the solar system

Mars begins its crawl up Castor's leg in the constellation Gemini the Twins in the final week of April. On its way it passes very close the the star cluster M35. (Stellarium)

Astro Bob 2:48 pm, Apr. 26, 2021

Astro Bob: Mars crawls up Castor's leg

A group of people watch the full moon rise from the shore of Brighton Beach in Duluth, Minn. on March 28, 2021. (Bob King)

Astro Bob 2:02 pm, Apr. 25, 2021

Astro Bob: Set your sights on the Super Pink Moon

On December 16, 1992, NASA's Galileo spacecraft looked back from a distance of about 3.9 million miles (6.2 million km) to capture this composite view of the Moon in orbit about Earth. The Moon is in the foreground; its orbital path is from left to right. Brightly colored Earth contrasts strongly with the Moon. (NASA)

Astro Bob 3:54 pm, Apr. 22, 2021

Astro Bob: Celebrate Earth Day in the moonlight

A couple watch a bright Lyrid meteor flash overhead during the 2013 shower. The Lyrids are the longest-observed of all meteor showers, dating back to 687 B.C. or more than 2,700 years ago. (John Chumack)

Astro Bob 1:43 pm, Apr. 20, 2021

Astro Bob: April showers bring Lyrid meteor flowers

Gemini is one the 12 constellations of the zodiac and represents two inseparable brothers from ancient Greek myth. The word Gemini comes from the Latin "geminos," meaning twins. (Urania's Mirror)

Astro Bob 2:57 pm, Apr. 18, 2021

Astro Bob: Let the moon deliver you to Gemini's doorstep

New processing techniques bring out fine details in the Veil Nebula's delicate threads and filaments of ionized gas photographed with the Hubble Space Telescope. Images taken through five different filters highlight light emitted by ionized oxygen (blues) and ionized hydrogen and nitrogen (reds). (ESA / Hubble & NASA, Z. Levay)

Astro Bob 5:28 pm, Apr. 15, 2021

Astro Bob: The Veil Nebula — Beauty in destruction

A fragile-looking crescent appears low in the western sky at dusk in March 2019. (Bob King)

Astro Bob 3:18 pm, Apr. 13, 2021

Astro Bob: How to feel the rhythm of the moon

The rear hazard-avoidance camera on the Mars Perseverance rover took this picture of what looks like a rainbow on April 4, 2021. It actually turned out to be a lens flare. (NASA / JPL-Caltech)

Astro Bob 11:43 am, Apr. 11, 2021

Astro Bob: Mystery rainbow on Mars explained

Immediately after the Perseverance rover released the Ingenuity helicopter it backed off so the craft could charge its batteries using the power of sunlight. (NASA / JPL-Caltech)

Astro Bob 4:07 pm, Apr. 8, 2021

Astro Bob: NASA preps Mars chopper for historic first flight

The Spring Triangle is big and easy to find and points the way to three prominent constellations of the April sky. (Bob King)

Astro Bob 2:03 pm, Apr. 7, 2021

Astro Bob: Star-hopping with the Spring Triangle and Great Diamond

See one or see them both! The waning crescent moon passes below Saturn and then Jupiter on April 6th and 7th at dawn. This view shows the sky facing southeast about an hour before sunrise. (Stellarium)

Astro Bob 2:45 pm, Apr. 5, 2021

Astro Bob: Waning moon makes back-to-back pairings with Jupiter and Saturn at dawn

This image of the interstellar comet 2I/Borisov was taken with the European Southern Observatory’s Very Large Telescope in late 2019, when comet passed near the Sun. Since it was travelling around 108,700 miles per hour (175,000 kph) the background stars appear as streaks of light as the telescope followed the comet’s trajectory. The colors result from combining photos taken in different colors and composited into a single image. (ESO / O. Hainaut)

Astro Bob 2:51 pm, Apr. 1, 2021

Astro Bob: Comet Hale-Bopp meets its match in interstellar Comet Borisov

Starlink satellites make multiple trails over Brazil in this time exposure taken on Dec. 10, 2019. Concern is growing over how the rapid increase in the number of satellites orbiting the Earth has artificially brightened the night sky. Currently, 60 new Starlinks are launched about every two weeks. At upper right, the camera also captured a bright meteor at the same time. (Egon Filter / CC BY-SA 4.0)

Astro Bob 1:55 pm, Mar. 30, 2021

Astro Bob: New study shows satellites are making the night sky brighter

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