The time to catch Comet T4 Lemmon is now, before it vanishes for another 36,000 years.
Often, icy interlopers creep up on the inner solar system, only to once again vanish into the abyss. Such is the case with long-period comet C/2021 T4 Lemmon, headed towards perihelion early next week.
What does the ancient coin found recently off the shores of Israel depict?
You never know what discoveries are waiting to be found in old records or artwork. A recent archaeological find sent us down just such an astronomical rabbit-hole, leading us to ideas that are fun and interesting to consider.
The night sky is a part of humanity’s natural heritage. Gazing up at the heavens is a unifying act, performed by almost every human that’s ever lived. Haven’t you looked up at the night sky and felt it ignite your sense of wonder?
But you can’t see much night sky in a modern city. And the majority of humans live in cities now. How can we regain our heritage? Can quiet contemplation make a comeback?
Now, watch for a rare event this weekend, with the final eclipse for 2018 coming up on Saturday, August 11th, with a partial solar eclipse spanning northern Europe and the Arctic.
What’s so unique about this eclipse? Well, not only is it the last one for 2018, but it’s part of three eclipses in the second eclipse season of the year. Most seasons only feature two eclipses (one lunar and one solar) but every few years or so, it is possible to have a season with three: either lunar-solar-lunar (such as occurred in 2013) or solar-lunar-solar.
This is only possible when the middle eclipse occurs very near ascending or descending node along the ecliptic. The nodes are where the path of the Moon, inclined 5.1 degrees relative to the ecliptic plane intersect it—when these nodes are occupied by an alignment of the Earth, Sun and Moon (known as a syzygy, a fine word in Scrabble to land on a triple word score, though you’ll need a blank tile for the third ‘y’) a solar or lunar eclipse occurs. For an eclipse triple play, the middle eclipse needs to happen very near a node crossing, producing a fairly long eclipse. That’s exactly what happened on July 28th, when the Moon crossed through descending node just over an hour after crossing out of the Earth’s umbral shadow after the longest lunar eclipse for the 21st century.
This also leaves the Moon close enough to the opposite ascending node two weeks post and prior to July 28th on July 13th and August 11th to just nick the Sun for a partial solar eclipse, one over the Antarctic and one over the Arctic.
Saturday’s partial eclipse touches down over the eastern coast of Canada at sunrise. From there, it sweeps eastward over Greenland, Iceland and the North Atlantic, with the Moon’s penumbra just grazing the northern United Kingdom before crossing over Scandinavia. Then, the shadow crosses over Asia, with a photogenic partial solar eclipse wrapping up at sunset over eastern China, the Koreas and the Russian far east.
Note that this eclipse is also a relative newcomer for its particular saros 155, as it is member 6 of a series of 71 eclipses. The saros just began less than a century ago on June 17th, 1928, and won’t produce its first total solar eclipse until September 12th, 2072 AD.
As of this writing, we’ve yet to see evidence of anyone carrying the eclipse live, though we’ll note it here if any webcast(s) surface.
When is the next one? Well, the next partial solar eclipse is on January 6th 2019, and the next total solar eclipse occurs on July 2nd, 2019.
Enter the Perseids
This weekend’s eclipse at New Moon also sets us up for a fine display of the Perseid meteors for 2018. This year, the Perseids are expected to peak on the morning of August 12th and August 13th. Watch for a zenithal hourly rate of 100 meteors per hour at the peak. A dependable annual favorite, the Perseids are debris remnants of period comet 109/P Swift-Tuttle.
Astronomer Gianluca Masi and the Virtual Telescope Project 2.0 will host a live webcast for the 2018 Perseids on August 12th starting at 20:30 UT.
Don’t miss the astronomical action worldwide this weekend, either live or online.
There’s nothing an astronomer – whether professional or amateur – loves more than a clear dark night sky away from the city lights. Outside the glare and glow and cloud cover that most of us experience every day, the night sky comes alive with a life of its own.
Thousands upon countless thousands of glittering jewels – each individual star a pinprick of light set against the velvet-smooth blackness of the deeper void. The arching band of the Milky Way, itself host to billions more stars so far away that we can only see their combined light from our vantage point. The familiar constellations, proudly showing their true character, drawing the eye and the mind to the ancient tales spun about them.
There are few places left in the world to see the sky as our ancestors did; to gaze in wonder at the celestial dome and feel the weight of billions of years of cosmic history hanging above us. Thankfully the International Dark Sky Association is working to preserve what’s left of the true night sky, and they’ve rightfully marked northern Chile to preserve for posterity.
I’ve often been asked the question, “Can the astronauts on the Space Station see the stars?” Astronaut Jack Fischer provides an unequivocal answer of “yes!” with a recent post on Twitter of a timelapse he took from the ISS. Fischer captured the arc of the Milky Way in all its glory, saying it “paints the heavens in a thick coat of awesome-sauce!”
Can you see stars from up here? Oh yeah baby! Check out the Milky Way as it spins & paints the heavens in a thick coat of awesome-sauce! pic.twitter.com/MsXeNHPxLF
But, you might be saying, “how can this be? I thought the astronauts on the Moon couldn’t see any stars, so how can anyone see stars in space?”
It is a common misconception that the Apollo astronauts didn’t see any stars. While stars don’t show up in the pictures from the Apollo missions, that’s because the camera exposures were set to allow for good images of the bright sunlit lunar surface, which included astronauts in bright white space suits and shiny spacecraft. Apollo astronauts reported they could see the brighter stars if they stood in the shadow of the Lunar Module, and also they saw stars while orbiting the far side of the Moon. Al Worden from Apollo 15 has said the sky was “awash with stars” in the view from the far side of the Moon that was not in daylight.
Just like stargazers on Earth need dark skies to see stars, so too when you’re in space.
The cool thing about being in the ISS is that astronauts experience nighttime 16 times a day (in 45 minute intervals) as they orbit the Earth every 90 minutes, and can have extremely dark skies when they are on the “dark” side of Earth. Here’s another recent picture from Fischer where stars can be seen:
For stars to show up in any image, its all about the exposure settings. For example, if you are outside (on Earth) on a dark night and can see thousands of stars, if you just take your camera or phone camera and snap a quick picture, you’ll just get a darkness. Earth-bound astrophotographers need long-exposure shots to capture the Milky Way. Same is true with ISS astronauts: if they take long-exposure shots, they can get stunning images like this one:
This image, set to capture the bright solar arrays and the rather bright Earth (even though its in twilight) reveals no stars:
Author’s note: This Superbowl Sunday event and 101 more like it are featured in our latest free e-book, 101 Astronomical Events for 2017, out now from Universe Today.
Sure, this Superbowl Sunday brings with it the promise of sacks, fumbles and tackles… but have you ever seen the Moon run down a star in the end zone? Just such an event, referred to as an occultation, happens this weekend for folks living around the Mediterranean and — just maybe for some sharp-eyed, telescope-owning observers based around the Caribbean region — this coming weekend.
Update: be sure to watch this Sunday’s occultation of Aldebaran by the Moon courtesy of Gianluca Masi and the Virtual Telescope Project live starting at 22:00 UT/5:00 PM EST:
We’re talking about Sunday’s occultation of the bright star Aldebaran by the 64% illuminated waxing gibbous Moon. This is the 2nd occultation of Aldebaran by the Moon for 2017 and the 28th of the current ongoing cycle of 49 spanning from January 29th, 2015 to September 3rd, 2018. The Moon actually occults Aldebaran and Regulus once for every lunation in 2017. We won’t have another year featuring the occultations of two +1st magnitude stars (Spica and Antares) again until 2024.
The event occurs under dark skies for observers based around the Mediterranean and under daytime afternoon skies for folks in central America, the Caribbean, northern South America and the Florida peninsula, including Astroguyz HQ based in Spring Hill, just north of the Tampa Bay area. We’ve managed to spy Aldebaran near the daytime Moon while the Sun was still above the horizon using binocs, and can attest that the +1st magnitude star is indeed visible, if you know exactly where to look for it.
Note that, like solar eclipses belonging to the same saros cycle, occultations of Aldebaran in the ongoing cycle drift north and westward from one to the next, to the tune of about 120 degrees longitude. Though most of North America sits this one out, we do get a front row seat for next lunation’s occultation of Aldebaran on the evening of March 4/5th. The next one is the best bright star occultation of Aldebaran by the Moon for North America in 2017. And be sure to check out the Moon this Sunday evening after the big game, and note Aldebaran hanging just off of its bright limb.
The ref will have a close call to make for this one. The northern grazeline in Florida might make this an especially interesting event to watch, though it’ll be challenge, as the occultation occurs in the afternoon under daylight skies. This crosses right along near the cities of Jacksonville and Gainsville. Clear, deep blue high contrast skies are key, and we’ll be watching from Astroguyz HQ north of Tampa Bay during this event.
Here are some key times from the occultation zone (noted in Universal Time):
Ingress: 20:08 UT/Moon altitude: 23 degrees
Egress: 20:34 UT/Moon altitude: 29 degrees
Ingress: 19:34 UT/ Moon Altitude: 49 degrees
Egress: 20:29 UT/ Moon altitude: 31 degrees
Ingress: 20:21 UT/Moon altitude: 37 degrees
Egress: 23:12 UT/ Moon altitude: 28 degrees
Tel Aviv, Israel
Ingress: 22:39 UT/Moon altitude: 16 degrees
Egress: 23:29 UT/Moon altitude: 5 degrees
Ingress: 21:49 UT/ Moon altitude: 61 degrees
Egress: 23:07 UT/ Moon altitude: 45 degrees
Note that this occultation spans five continents, a truly worldwide event. The International Occultation Timing Association (IOTA) maintains a page with an extensive list of times for cities worldwide. Note that when the Moon tackles Aldebaran, its also crossing the scrimmage line of the Hyades open cluster, so expect numerous occultations of fainter stars worldwide as well.
Aldebaran is the brightest star along the Moon’s path in our current epoch, along with runner-ups Spica, Regulus and Antares. Though Aldebaran is 1.5 times the mass of our Sun, it’s also 65 light years away, and only appears 20 milliarcseconds (mas) in size, about the equivalent of a 40 meter diameter crater from the distance of the Moon. Still, you might just notice a brief pause as Aldebaran fades then winks out on the dark limb of the Moon, a tiny hitch betraying its diminutive angular size.
And the clockwork gears of that biggest game of all, the Universe, grind on. Don’t miss this first big ticket astronomical event for February 2017, coming to a sky above you. Next up, we’ll watching out for another bright star occultation, two eclipses, and the close passage of a comet near the Earth.
If you’re like a lot of people, you don’t own a telescope but still have a passionate curiosity for what’s going on over your head. Good news! There’s lots to see up there without any equipment at all. This is the premise of my new book titled Night Sky with the Naked Eye, a guide to the wonders of the night sky that anyone can enjoy and understand whether you live in an apartment in the city or cabin 50 miles from nowhere.
I’ve always been amazed at how accessible the universe is. To make that personal connection to the cosmos we only need acquire the habit looking up. Total eclipses, monster auroras and rich meteor showers get a lot of coverage and rightly so, but there’s a lot of other stuff up there. Little things that stoke our sense of wonder happen all the time: Earth’s rising shadow at sunset, nightly satellite flyovers, the beauty of an earth-lit crescent moon or seeing your shadow by the light of Venus.
Skywatching not only informs and delights, it has the power to expand our perspective and sense of place in the scheme of things. Gazing up at the Milky Way on a dark summer night, we feel both humbled and fortunate to be alive. The night sky’s elixir of beauty, timelessness and possibility feeds an inner quietude that can be our strength in stressful times.
While the book touches on the contemplative aspects of skywatching, the bulk of it is activity-oriented, intended to inspire you to get outside. I’ve got tips on weather-watching and making the most of online resources like Clear Dark Sky and satellite imagery to help you find clear skies for that must-see special event. And if light pollution is a problem where you live, we explore ways to make a difference in reducing it as well as using online atlases to find a dark observing site.
The book covers the basics of celestial and planetary motions, how to find the brighter constellations and naked-eye deep sky objects along with suggested night sky viewing activities to share with friends and family. There are 1o chapters in all:
Chapter 1: Wave “Hi!” to the Astronauts
Chapter 2: Anticipating the Night
Chapter 3: Rockin’ N’ Rollin’ Earth
Chapter 4: Dive Into the Dippers
Chapter 5: Four Seasons of Starlight
Chapter 6: Meet the Rabbit in the Moon
Chapter 7: Face to Face with the Planets
Chapter 8: Wish Upon a Shooting Star
Chapter 9: Awed by Aurora
Chapter 10: Curiosities of the Night
Not everything is a billion miles away. We also take time to examine and appreciate closer-to-home phenomena that are part of the nighttime experience like lunar halos, light pillars and the aurora borealis. No observers’ guide would be complete without challenges. How about seeing craters on the moon with no optical aid or spotting the gegenschein? It’s all here.
Because the Internet has become an integral part of our lives, the book includes numerous online resources as well as useful mobile phone apps related to constellation finding and aurora tracking and tips on night sky photography.
Whether for yourself or to give as a holiday gift for a budding skywatcher, I hope you check out my book, which will be featured in a special promotion here at Universe Today. It would be my privilege to serve as your night sky guide.