Astro Bob

The Inspiration4 ship and crew pass beneath the bright star Altair around 8:42 p.m. Friday night, September 17. At the same time, Object-B, a rocket stage from an earlier Japanese satellite launch, crosses the same part of the sky.  Bob King Sometimes satellites and spacecraft don't show up at their predicted times. One of the main reasons this happens is when mission control decides to raise or lower the object's orbit by firing the ship's thrusters.  Last night, unbeknownst to most, SpaceX lowered the orbit of historic Inspiration4 space capsule sometime before or during its pass over the U.S. When a spacecraft's altitude is lowered, it appears lower in the sky and moves more quickly. A faster speed also means it will arrive in view earlier than the original time. The higher the orbit the more slowly the satellite travels, the same way Earth takes more time to circle the sun compared to Mercury.  I set up the camera a little more than 10 minutes in advance just to tes...

The SpaceX Inspiration4 crew during a launch day rehearsal, From left:  Chris Sembroski, Dr. Sian Proctor, Jared Isaacman, and Hayley Arceneaux. Space X, CC0 By now you will have heard of the Inspiration4 orbiting spacecraft that's ferrying a crew of four civilians around the planet every 96 minutes. Although they all trained for six months for the flight, the ship is run by computer. The primary goal of the mission is to raise money for St. Jude's Children's Research Hospital. Wednesday night's launch went flawlessly, with the spacecraft currently orbiting the Earth at an altitude of about 360 miles (580 km) and inclination of 51.6°. That steep tilt, identical to the space station's inclination, means that the craft is widely visible from many locations on the ground. The only down side is that it splashes down in the Atlantic Ocean off the coast of Florida sometime on Saturday or Sunday, September 18-19. That leaves just one or two nights to see it. I had hoped t...

A participant at Northern Nights Star Fest uses a filtered computer to monitor the progress of a photo taken through his telescope. Red filters preserve night vision. No white lights are allowed on the observing field during the event. Ben Huset   Last weekend I attended the 10th annual Northern Nights Star Fest  (NNSF) held by the Minnesota Astronomical Society (MAS). Members flee light-polluted backyards and head north to Long Lake Conservation Center in north-central Minnesota to revel in dark skies. I spoke at the event and had the time of my life. We've all been a little starved of company the past year and a half because of COVID-19 fears. Getting together with other amateur astronomers for face-to-face conversation and to share the night sky was balm for all. I'm grateful the MAS provided the opportunity. MAS member Jerry Jones speaks Friday night about the work of Edward Pickering and the women at Harvard College Observatory to elucidate the properties of stars throug...

A bright green arc and bundles of rayed curtains light up the northern sky during an auroral display on March 19-20, 2021. Bob King As soon as it gets dark, observers across the northern U.S., Canada and possibly the Midwest should keep watch for the aurora. Since this morning (August 27) the Earth's magnetic envelop has been buffeted by strong solar winds from a coronal mass ejection (CME) that occurred on August 23. Activity's still ongoing as of 7 p.m. CDT. Spaceweather forecasters are predicting a G1 or minor storm through about 10-11 p.m. I've got clouds and rain here all night, but hopefully conditions are better where you live. With moonrise around 10:30 p.m. this evening we'll have a nice window of darkness. Find a location with a dark sky and look above the northern horizon for a greenish-colored arc of light reaching from northeast to northwest. You may even see vertical rays extending upward from this arc higher in the sky.  Let us know if you spot anything. ...

The half-moon will shine just above the bright double star Zubenelgenubi in Libra tonight (August 14), making for a stellar sight in binoculars.  Stellarium It's fortunate that stars have such cool names: Nunki, Aldebaran, Rigil Kentaurus, Betelgeuse just to name a few. One of the most fun to say out loud is Zubenelgenubi (zoo-BEN-el-je-NEW-bee), which also goes by the more prosaic moniker Alpha Librae. It forms part of the outline of the diamond-shaped Libra the Scales, a zodiac constellation which represents weighing scales.  In this 16th century globe created by Gerard Mercator Libra is shown both as a balance and the scorpion's claws. Public domain In ancient times, the Babylonians and Greeks alternatively pictured Libra as the Claws of the Scorpion, and included it as part of the neighboring constellation Scorpius. Its brightest stars still bear Arabic names that refer to the arachnid's pincer-like claws. Zubenelgenubi means "northern claw"; Zubeneschamali (z...

The dawn lunar crescent displays bright earthshine as it rises over Lake Superior near Duluth in July 2019. Earthshine is sunlight reflected from the Earth to the moon and then back to our eyes. Watch for a similar scene on Tuesday morning, July 6.  Bob King It may be different where you live, but someone turned up the heat this month. The air feels like hot breath, but sweeter, filled with delicious scents of green plants, pine sap and flowers. You know it's summer when the Summer Triangle unfurls across the southeastern sky at nightfall, and Scorpius drags his tail along the horizon.  This is the view facing east-northeast about 90 minutes before sunrise on Tuesday, July 6. The moon and Pleiades should be well visible without optical aid. The Hyades cluster may require binoculars for a good view because it's lower in the sky. Stellarium Most of us seek shade during the day. After the stress of sunlight departs at dusk, we slow our pace and open our senses to new sights and s...

  The sun and sky were "on fire" last night, July 2, colored by forest fire smoke. Bob King The past few days and nights you may have noticed how much less blue the sky appears even with the sun shining. Today (July3) in northern Minnesota, the meteorologists will tell you it's clear and sunny, but the sky is actually gray. As for the sun, even 3 hours past sunrise it's still tinged pale orange. This satellite view on June 30, 2021 shows a plume of smoke moving south out of Canada into Minnesota. Currently, the Midwest and far West are under smoky skies. NOAA These are symptoms of smoke from wildfires across the western and southwestern U.S. as well as Canada. Today, July 3, smoke plumes loom over the Midwest and far West. Most of the smoke lies at high elevations so you can't smell it. But occasionally, winds bring it closer to the ground, and the air smells like a campfire. Too much of it can pose a health hazard. Sunspot region 2835 shows through the haze just ...

The sun appears in annular eclipse on Oct. 3, 2005. The black silhouette is the new moon. Abel Pardo Lopez On Thursday morning, June 10 , the new moon will glide in front of the sun, and observers across the eastern U.S. and Canada, along with much of Europa and Asia, will witness a solar eclipse. This will be an annular or ring eclipse because the moon is farther from Earth than usual and appears too small to completely cover the sun. Instead, sunlight will spill around its edges to form a ring. The moon's distance varies because it orbits the Earth in an ellipse, not a circle. Lucky skywatchers in the path of annularity will see a brilliant ring or annulus of sunlight encircling the moon at maximum eclipse. That path begins at sunrise on the far north shore of Lake Superior in Ontario and sweeps across Hudson Bay, northwestern Greenland, the North Pole and ends at sunset in Siberia.  Here are details of the June 10th eclipse for a sample of cities. Obscuration is the area of the...

  The seven phases of the eclipse are listed at left with time zones across the top — EDT (Eastern Daylight); CDT (Central Daylight); MDT (Mountain Daylight); PDT (Pacific Daylight); Alaska Daylight (AKDT) and Hawai'i-Aleutian Standard Time (HAST). Find your time zone, then read down the column for your local times. Blank boxes indicate parts of the eclipse that won't be visible from that time zone. Here's a last quick look at the upcoming total lunar eclipse that will grace skies across the Americas Wednesday morning, May 26th . From most locations it occurs as night gives way to dawn. The table shows the local viewing times for six different time zones from the East Coast to Hawai'i. If you live in Denver, for example, the partial eclipse begins at 3:45 a.m. local time, with the moon entering total eclipse at 5:11 a.m. shortly before sunrise. Only folks living in the Pacific Time Zone and points west will see totality in a dark sky. Wednesday's dawn eclipse will r...

During this morning's G3 storm — modeled here around 9 a.m. CDT — the aurora expanded and brightened across Siberia. NASA / NOAA Earlier this morning (May 12) from about 7-9 a.m. Central Time a strong G3 geomagnetic storm rattled the planet's magnetic field. Too bad the sun was shining or the northern half of the U.S. and Canada would have witnessed a fine display of northern lights. Although it's difficult to say whether the disruption could spill over into tonight there's always a possibility.  This is one of the two coronal mass ejections related to the filament eruption and a modest solar flare on May 9. NASA / ESA  For now, the space weather forecasters predict "active" but not storm conditions this evening from nightfall till dawn. That typically means a little bit of aurora within 10° of the northern horizon for observers in the northern states. The cause of the excitement is a tendril of hot gas called a filament, which the sun flung into space on Ma...

The first module of the Chinese Tianhe-1 space station passes across the Sagittarius Milky Way in this 30-second time exposure taken at 3:56 a.m. May 5. Bob King UPDATE 10:45 p.m. CDT: The rocket stage reentered Earth's atmosphere around 10:44 p.m. CDT May 8 (Saturday), landing in the Indian Ocean a short distance west of the Maldives according to China's National Space Agency (CNAS). Most of the booster was destroyed.  Sometime in the next 24-hours a 23-ton rocket stage is expected to fall to Earth somewhere between 41.5° north latitude and 41.5° south latitude. If you live north or south of that range, you're safe. (Find you latitude here ). If not, there's a extremely small but non-zero possibility that space junk could land in your backyard. The reason it will only fall within that band of latitude is because the stage orbits the Earth inclined 41° to the planet's equator. Tumbling end over end, the Chinese rocket booster flashes across the sky over Rome, Italy ...

Our last G2 moderate storm occurred on March 19-20, 2021 when bright rays and arcs played about the northern sky all night. Bob King UPDATE7:30 p.m. CDT: The storm's arrival time has been revised. A G1 minor storm should be underway from nightfall until around 10 p.m. Central Time, then develop into a G2 moderate storm from 10 p.m. to 1 a.m.  I sat up in my chair when I saw the NOAA space weather forecast yesterday. Scanning the April 25th column, the number "6" jumped out. The numbers indicate the Kp index,  a measure of how rattled Earth's magnetic field becomes when it's hit by a wave of particles from the sun. The index ranges from no disturbance (0) to severe geomagnetic storm (9). The higher the number the greater the chances of seeing the aurora borealis. For the northern regions of the northern states, a Kp of 5 often bodes a minor geomagnetic storm and a modest auroral display low in the northern sky. A Kp of 6 takes us to the moderate or G2 geomagnetic...