No question is too small or too big for our nation’s curators.

You might not get a day off from work for Ask a Curator Day, but we can assure you, it’s a pretty big deal. On September 19, curators from across the world will be standing by the ready to take your questions and turn them into expert-crafted gold, or at least point you in the right direction. It’s as easy as 140 characters and a hashtag.

Using Twitter and the tag #askacurator, you can ask whatever burning query is on your mind. Experts from Sri Lanka to Switzerland will be fielding questions all day long. And, of course, the Smithsonian will be participating, including the American History Museum (@amhistorymuseum), the National Air and Space Museum (@airandspace), the Freer and Sackler Gallery (@freersackler), the National Museum of African Art (@nmafa) and the National Postal Museum (@postalmuseum).

On the American History Museum blog, meet the experts in advance of the event, including Katherine Ott, a curator in the Division of Medicine and Science who says, “Ask me about ephemera. It’s a weird word—and I love it.” Eric Jentsch, Deputy Chair of the Division of Culture and the Arts, meanwhile, can’t wait to discuss everything from pop culture to sports to one of his favorite finds, an Urkel lunchbox.

At the Postal Museum, historian Nancy Pope, curator of philately Daniel Piazza and curator of postal history Lynn Heidelbaugh are ready to take your questions.

And because good questions (hey, no such thing as a bad one, right?) deserve good answers every day, Smithsonian magazine invites all comers to “Ask Smithsonian,” where we’ll hook your musings up with the appropriate curator all year round, and possibly publish your name and your question in the magazine.

Tweets about “#askacurator”

How much is the Hope Diamond worth? Ask Smithsonian.

Our inquisitive readers are rising to the challenge we gave them last month. The questions are pouring in and we’re ready for more. Do you have any questions for our curators? Submit your questions here.

How much is the Hope Diamond worth? — Marjorie Mathews, Silver Spring, Maryland

That’s the most popular question we get, but we don’t really satisfy people by giving them a number. There are a number of answers, but the best one is that we honestly don’t know. It’s a little bit like Liz Taylor’s jewels being sold in December—all kinds of people guessed at what they would sell for, but everybody I know was way off. Only when those pieces were opened up to bidding at a public auction could you find out what their values were. When they were sold, then at least for that day and that night you could say, well, they were worth that much. The Hope Diamond is kind of the same way, but more so. There’s simply nothing else like it. So how do you put a value on the history, on the fact it’s been here on display for over 50 years and a few hundred million people have seen it, and on that fact it’s a rare blue diamond on top of everything else? You don’t. – Jeffrey E. Post, mineralogist, National Museum of Natural History

What’s the worst impact of ocean acidification so far?- Nancy Schaefer, Virginia Beach, Virginia

The impacts of ocean acidification are really just starting to be felt, but two big reports that came out in 2011 show that it could have very serious effects on coral reefs. These studies did not measure the warming effect of carbon dioxide in the atmosphere, but rather its effect of making the ocean more acidic when it dissolves in the ocean. Places where large amounts of carbon dioxide seep into the water from the sea floor provide a natural experiment and show us how ocean waters might look, say, 50 or 100 years from now. Both studies showed branching, lacy, delicate coral forms are likely to disappear, and with them that kind of three-dimensional complexity so many species depend on. Also, other species that build a stony skeleton or shell, such as oysters or mussels, are likely to be affected. This happens because acidification makes carbonate ions, which these species need for their skeletons, less abundant.

Nancy Knowlton, marine biologist
National Museum of Natural History

Art and artifacts from ancient South Pacific and Pacific Northwest tribes have similarities in form and function. Is it possible that early Hawaiians caught part of the Kuroshio Current of the North Pacific Gyre to end up along the northwest coast of America from northern California to Alaska? — April Amy Croan, Maple Valley, Washington

Those similarities have given rise to various theories, including trans-Pacific navigation, independent drifts of floating artifacts, inadvertent crossings by ships that have lost their rudders or rigging, or whales harpooned in one area that died or were captured in a distant place. Some connections are well-known, like feather garment fragments found in an archaeological site in Southeast Alaska that appear to have been brought there by whaling ships that had stopped in the Hawaiian Islands, a regular route for 19th-century whalers. Before the period of European contact, the greatest similarities are with the southwest Pacific, not Hawaii. The Kushiro current would have facilitated Asian coastal contacts with northwestern North America, but would not have helped Hawaiians. The problem of identification is one of context, form and dating. Most of the reported similarities are either out of their original context (which can’t be reconstructed), or their form is not specific enough to relate to another area’s style, or the date of creation cannot be established. To date there is no acceptable proof for South Pacific-Northwest Coast historical connections that predates the European whaling era, except for links that follow the coastal region of the North Pacific into Alaska.

William Fitzhugh, archeologist
Natural History Museum