Nasa is tracking an asteroid dubbed the "Great Pumpkin" that will fly past Earth on Halloween. Officially named Asteroid 2015 TB145, it is flying so close that scientists are hoping to observe it in "unprecedented" levels of detail.
What do we know about the Great Pumpkin?
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.
Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
It is estimated to be 400 metres wide and is being tracked with several optical observatories and radar equipment. It was discovered on 10 October by the University of Hawaii's Panoramic Survey Telescope and Rapid Response System, which is part of the Nasa-funded Near-Earth Object Observation (NEOO) programme. Sometimes called "Spaceguard", the NEOO programme keeps a watch on the skies, hunting for asteroids that might hit the planet and predicting their paths through space.
When will it fly past?
The asteroid is due to fly past Earth on October 31 at 10.05am PDT – 5.05pm in the UK.
Are we in danger?
No. Nasa describes it as a "close pass" but says the Great Pumpkin will travel at a "safe distance slightly further than the moon's orbit". According to Paul Chodas, manager of the Centre for Near Earth Object Studies in California, it will be no closer than about 300,000 miles at its nearest point of approach. "Even though that is relatively close by celestial standards, it is expected to be fairly faint, so night-sky Earth observers would need at least a small telescope to view it," says Chodas. Its "gravitational influence" is so small that it will have "no detectable effect on the moon or anything here on Earth, including our planet's tides or tectonic plates", says Nasa.
Why is it important?
Its close approach and size suggests it will be "one of the best asteroids for radar imaging we'll see for several years", says Lance Benner, who leads Nasa's asteroid radar research programme. "We plan to test a new capability to obtain radar images with two-metre resolution for the first time and hope to see unprecedented levels of detail," he says. With radar images as fine as two metres per pixel, Nasa says it should be able to discover a "wealth of detail about the object's surface features, shape, dimensions and other physical properties". The next closest known approach by an object this large is expected to be in August 2027, when asteroid 1999 AN10 that's around 800 metres in size is due to pass the Earth from about 238,000 miles away.
-
5 hilariously cold cartoons about the Alaska summitCartoons Artists take on the Alaskan totem pole, a peace flag, and more
-
Journalists killed in Gaza: a chilling assaultIn the Spotlight Anas al-Sharif and three of his Al Jazeera colleagues were targeted by the IDF
-
Crossword: August 16, 2025The Week's daily crossword puzzle
-
Hurricanes are not exclusive to Earth. They can happen in space.Under the radar These storms may cause navigational problems
-
Why does the US want to put nuclear reactors on the moon?Today's Big Question The plans come as NASA is facing significant budget cuts
-
Answers to how life on Earth began could be stuck on MarsUnder the Radar Donald Trump plans to scrap Nasa's Mars Sample Return mission – stranding test tubes on the Red Planet and ceding potentially valuable information to China
-
The treasure trove of platinum on the moonUnder the radar This kind of bounty could lead to commercial exploitation
-
Why Elon Musk's satellites are 'dropping like flies'Under The Radar Fierce solar activity destroying Starlink satellites
-
Why is Nasa facing a crisis?Today's Big Question Trump administration proposes 25% cut to national space agency's budget in 'extinction-level event'
-
Full moon calendar 2025: when is the next full moon?In depth When to see the lunar phenomenon every month
-
Earth's oceans were once green and could one day turn purpleUnder the radar The current blue may be temporary
