What’s that big, bright thing in the eastern sky?

This delightfully abstract Martian landscape shows frozen CO2 filling pits near Mars' south pole during late summer. The small pits at center are about 200 feet across. Photo taken by the orbiting Mars Reconnaissance Orbiter. Click to enlarge.Credit: NASA/JPL/University of Arizona

Late summer in Mars’ south polar region is a lot colder than ours on Earth. During winter, carbon dioxide freezes out and precipitates across the polar region. When summer arrives, much of that ‘dry ice’ vaporizes or sublimates into gas form and returns to the atmosphere. In the planet’s south polar region, it stays cold enough even during the summer for some of the dry ice to stick around. In this stunning image from Mars, we see a portion of the permanent southern polar cap. Flat-floored brown pits are filled with an estimated 10 feet of dry ice. Wouldn’t you just love to strap on some boots and go for a ski?

I watched a movie last night and so didn’t step out to walk the dog until after 11. Not only was I greeted by a warm, fragrant breeze, but Jupiter stared me straight in the face. You may have experienced a recent Jupiter encounter and possibly wondered what that hugely bright object was in the eastern sky.

Jupiter is that big, bright object in the eastern sky around 11 p.m. local time as you face east. It's in the small constellation of Aries. Created with Stellarium

The biggest of the eight planets is the brightest object outside the moon visible in the night sky right now. It rises around 9:30 p.m. but doesn’t clear the local scenery until after 10:30. Just above the planet is the “crooked index finger” of the constellation Aries the Ram, which appears temporarily fainter than normal because of moonlight. Jupiter is brilliant for a couple reasons: it’s huge and covered in clouds like the planet Venus. Clouds reflect light well and Jupiter’s 88,000 mile girth — 11 times Earth’s diameter –  provides lots of clouds to reflect sunlight.

The planet is presently 399 million miles from us. Light traveling from Jupiter at 186,000 miles per second takes 36 minutes to reach your eyeballs, so a radio transmission between Earth and an orbiting spacecraft would take an hour and 12 minutes to make the round trip. As we explore the outer solar system, we learn great patience and an appreciation for distance.

This map simulates a binocular view of Jupiter and its four brightest moons tonight facing east around 11 p.m. G = Ganymede, I = Io, C = Callisto and E = Europa

Jupiter has more moons than any planet in the solar system with 63 at last count. Most are very small, probably captured stray asteroids, but four are hefty globes similar in size to our own moon. Each is visible in ordinary binoculars as a tiny point of light snugged up very close to the planet. What gives them away when viewed this way is that they typically lie in a straight line on either side of the planet. That’s because they all orbit in the same plane about the planet’s equator. Since each moon also lies at a different distance from Jupiter, they orbit the planet with different periods. Io, the closest, completes its orbit in just 1.8 days while Callisto, the farthest, takes 16.7 days.

When you combine the four different periods, you’re guaranteed a unique display of moons every single night through your binoculars. Occasionally one moon or another might be behind the planet or too close to Jupiter’s glare to see, so the number of moons visible on a particular night can vary from one (or none!) to four. No wonder Galileo saw Jupiter as a solar system in miniature.

To find out which moons are which for any night you’re looking, click over to Sky and Telescope’s Jupiter’s Moons utility. It shows you a little diagram with the moons’ locations at the current time as well as a list of moon eclipses and transits for telescopic observers. If you want to know what to expect in advance, you’ll need to convert the time shown, which is in UT or Universal time, to your time zone. For instance, 11 p.m. Central time September 9 equates to 4 a.m. UT September 10 or 5 hours ahead. UT is 4 ahead of Eastern time, 6 ahead of Mountain and 7 ahead of Pacific. Have fun

26 thoughts on “What’s that big, bright thing in the eastern sky?

  1. I saw something last night it lit up the clouds in front of it, I assumed it was they supernova (dont laugh) The moon was rising to the right a bit above it, was that Jupiter? I’m in Northern N.J, US. It was brighter tan I ever saw it before.

    • Hi Toni,
      It sounds to me like Jupiter. It’s bright enough to set the clouds aglow and would have been well to the left and below the moon. I wish the supernova were that bright. Nope, you need a telescope or large binoculars to see it.

        • It is not Jupiter or Mars or any other planet. For one thing it is not round, it’s oblong. Why can’t you ever get a straight answer here. Do not ever answer a question with a question. We all know what a planet looks like. It is NOT a planet, so if you don’t know what it is don’t answer.

  2. I think I have been seeing Jupiter in the sky for a while now, I live in England (North East) so would Jupiter be appearing in the Western sky from my perspective? It is a remarkably bright object, whatever it is I see, and appears blueish and large as well as bright

    • Hi Mark,
      Yes, you’ve seen Jupiter, but there are two bright planets in the western sky. The brighter and currently highest one is Venus. Just below it is Jupiter.

      • Thank you, I’ve been wondering for a while what I could be seeing. I know Venus is supposed to be coloured green, but what colour do Venus and Jupiter appear in the night sky? Could one appear red because of the “red sunset” effect close to the horizon?

        • Hi Mark,
          Venus normally looks pure white, while Jupiter has a very slight yellow tinge. I’ve never seen either look red near the horizon, but it certainly would be possible. Mars is the only distinctly orangish-red planet.

  3. Hi Bob,

    I know Venus and Jupiter are in the western sky and are about to trade places, but what is currently in the eastern sky? It’s very close to 180 degrees opposite Venus and Jupiter, it has an orange (or possibly yellow) tint, appears slightly bigger than a star and is very (!) visible to the naked eye. I first noticed it within the last two weeks.

    Thanks,
    Pete

  4. What is the huge light in the eastern sky at three AM these past few months? It has a smaller but still second brightest light in the sky up and to the right of it.This past winter these lights were in the west at midnight.

  5. BOB..AT ABOUT 4:30 AM IN BELIZE , WE OBSERVED THE BRIGHTEST OBJECT IN THE EASTERN SKY AT ABOUT 9 OCLOCK HIGH.. IT WAS THE BRIGHTEST POINT I HAVE SEEN OTHER THAN THE SUN OR THE MOON..

    IT WAS BRIGHT WITH A BLUE TINT SLIGHTLY OBLONG…VERY VERY BRIGHT
    AND LARGE..NO TELESCOPE NEED.. WHAT WAS THAT???
    THKS

  6. I live at South East Asia, Malaysia. I am seeing a big bright object on a clear night tonight ( Nov.13) It doesn’t twinkle however, it appear to change it brightness quite constantly. When the brightness dimmed, it appeared to be smaller, but when it is brighter, it looks bright & big. What planet is this ??

  7. Last night I saw the large bright ‘star’ to the East, and pulled out my iPad star walk program and it said it was Jupiter. So I pull out my small telescope and line it up and take a look. Its just a large white blob. I can’t seem to get a good focus on it. Then I see next to it. (down and to the left) a clear planet with stripes, that I can only assume is Jupiter. I can’t imagine I would see its moons so clearly. From my eye I would say it was 3-4 mm wide. Maybe a bit larger.
    The white object was easily 4-5 times larger than the planet. I moved things around and it clearly was not something on my lens, or something in the way. My wife came out and took a look. I told her it was Jupiter and one of its moons. But to be honest, I do not think that is what we were looking at. According to starwalk, there should be nothing else there except stars and this was way to big to be a star. Perhaps an asteroid that just happened to be in the path? But this was almost perfectly round?
    Thoughts?

    • Hi Ben,
      My first thought is that you saw a bright internal reflection of Jupiter. I’ve seen it in my telescope occasionally especially when Jupiter’s just outside the field of view. Any others care to comment?

  8. The object that I see moves north to south and up and down, like it is adjusting. It is the brightest object in the eastern sky and I see it often. I have been seeing it for 15+ yrs. When it moves, you can see it w/the naked eye and it moves up and down quickly. Almost jerky. Sometimes it moves a long ways south in just a few seconds. Like a plane, but not a plane. When it moves up and down, it is a much shorter space. I have looked at it through a telescope and it is blue and red. I couldn’t see it clearly, but it was red at the bottom and basically round. Then there was a blue “tower” that look like a ladder and was wider at the bottom. ????

    • Hi Sam,
      I’d guess you’re looking at a bright planet, possibly Jupiter, but I don’t know for sure. Any way you could take a picture of it? You could also sketch its position including the surrounding stars and shoot that with a cellphone. My e-mail is: rking @duluthnews.com

  9. I saw Jupiter last night and it was such a surprise. I came to this website for more information. Thank you for your candor and open encouragement of others’ thoughts. It’s refreshing. If you are an astronomy Buff, i have Somers images caught on m’y iPhone which are of a disturbing nature, I have shqred t hem with Harvard’s Prof. David Charbeaneax. The incident occurred in the early morning hourd of Sept. 11, 2012.

  10. NOT A STAR OR PLANET. IT,S TOO LIGHT OUTSIDE TO SEE PLANETS OR STARS. SUN IS GETTING READY TO RISE. IT,S THE SUN REFLECTING OFF A SATELITE. GPS OR COMMUNICATIONS. THAT IS WHAT IT IS.

    • Patrick,
      All those things would be moving, not standing still unless they were communications satellites in geosynchronous orbit, in which case they would be much too faint to see with the naked eye. Iridium satellites briefly get brighter than Venus but fade back to invisibility within seconds. So it’s possible you saw that, but if it stayed put for any length of time, Venus is the only thing out there right now that’s bright (and still enough) enough to see shortly before sunrise.

Leave a Reply

Your email address will not be published. Required fields are marked *

*

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>